Research Article |
Corresponding author: Thomas A. Neubauer ( neubauer@snsb.de ) Academic editor: Martin Haase
© 2018 Thomas A. Neubauer, Sabrina van de Velde, Tamara Yanina, Frank P. Wesselingh.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Neubauer TA, van de Velde S, Yanina T, Wesselingh FP (2018) A late Pleistocene gastropod fauna from the northern Caspian Sea with implications for Pontocaspian gastropod taxonomy. ZooKeys 770: 43-103. https://doi.org/10.3897/zookeys.770.25365
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The present paper details a very diverse non-marine gastropod fauna retrieved from Caspian Pleistocene deposits along the Volga River north of Astrakhan (Russia). During time of deposition (early Late Pleistocene, late Khazarian regional substage), the area was situated in shallow water of the greatly expanded Caspian Sea. The fauna contains 24 species, of which 16 are endemic to the Pontocaspian region and 15 to the Caspian Sea. The majority of the species (13) belongs to the Pyrgulinae (Hydrobiidae), a group famous for its huge morphological variability in the Pontocaspian region. The phenotypic diversity has led to an inflation of genus and species names in the literature. New concepts are proposed for many of the genera and species found in the present material, with implications for the systematics and taxonomy of the entire Pontocaspian gastropod fauna. Laevicaspia vinarskii sp. n. is described as a new species. This contribution is considered a first step in revising the Pontocaspian gastropod fauna.
biodiversity, endemism, long-lived lakes, non-marine Gastropoda, Quaternary
The Caspian Sea is Earth’s largest inland water body. With an area of 378,100 km² it covers about 40% of the world’s continental surface water (
During the Pleistocene, several major transgressive–regressive cycles caused recurrent connections between Black Sea and Caspian basins, which were accompanied by dramatic changes in lake size, salinity and biotic assemblages (e.g.,
In order to predict future biodiversity loss as a response to natural or anthropogenically induced environmental change, it is vital to document and understand the species richness and development of the endemic fauna over longer temporal scales. For this purpose, a sound taxonomic framework is required. The extreme morphological variability of many of the described species complicates taxonomy and, thereby, hampers reliably diversity assessments. Preceding taxonomic studies carried out in the 19th and 20th century have produced a plethora of available species names, partly based on minor morphological deviations. Taxonomic works are hampered by (1) the inadequate nature of descriptions and illustrations, (2) the apparent loss of much of the material, (3) the few and hugely variable morphological characters in some of the groups, and (4) the apparent recent loss of many of the species, which makes combined morphological and molecular approaches impossible. Presently, the statuses of most Caspian endemic gastropods, especially of the numerous representatives of the Pyrgulinae (Hydrobiidae), are poorly resolved.
The present contribution details a diverse gastropod fauna from upper Khazarian (Upper Pleistocene) deposits from the northwestern part of the Caspian Basin, at that time witnessing a major transgressive event (
Geographic overview of the Pontocaspian region, with indication of the extent of the late Khazarian (early Late Pleistocene) transgression. The star marks Selitrennoye. Paleo-lake level was modeled in ESRI ArcGIS 10.4 based on
The studied mollusk fauna derives from deposits exposed near the small village of Selitrennoye (also as Selitrennoe; Russ. Селитренное) along the left bank of the Akhtuba River, a distributary of the Volga River (Russia) (Fig.
Approximately 5 kg of sediment were collected by F.W. in September 2015 and were washed over a 0.5 mm sieve before sorting. All material is stored at the Faculty of Geography of the Moscow State University under collection numbers LV 201501–201530 and 201731–201750 and at the Naturalis Biodiversity Center, Leiden, The Netherlands, under collection numbers RGM 1309784–1309793, 1309797–1309856, 1310190–1310249, and 1310252–1310258.
Macro-photographs of the specimens were taken with a Leica M165 C stereomicroscope with attached DFC420 camera, using the focus stacking function of the Leica Application Suite software v. 4.4.0 at the Naturalis Biodiversity Center, Leiden. SEM images were acquired on a JEOL JSM-6480LV at the same institute. Specimens were coated with a 20 nm thick platinum-palladium alloy in a Quorum Q150T S coater.
For every species, a number of specimens was measured as representatives of its morphological spectrum. Shell measurements for Theodoxus are given as height × largest width (perpendicular to height) × second-largest width (perpendicular to both other axes); for all other species, measurements are given as height × width. Counting of protoconch whorls follows the method used by
Abbreviations used are:
P/T protoconch/teleoconch;
MSU Moscow State University, Moscow, Russia, Faculty of Geography;
RGM Naturalis Biodiversity Center, Leiden, The Netherlands, coll. Fossil Mollusca (formerly Rijksmuseum van Geologie en Mineralogie);
ZIN Zoological Institute of the Russian Academy of Sciences, St. Petersburg, Russia.
We tried to locate the depository of type specimens for all identified species, but this was successful only for a part of the fauna. In particular, much of the type material of the species described by
Theodoxus lutetianus Montfort, 1810 [currently considered as a synonym of Theodoxus fluviatilis (Linnaeus, 1758)]; by original designation. Recent; Europe.
1838 Neritina liturata m. Eichwald: 156–157 [non Neritina liturata Schultze, 1826].
1841 Neritina liturata m. – Eichwald: 258–260, pl. 38, figs 18–19 [non Schultze, 1826].
1855 Neritina liturata m. – Eichwald: 307–308 [non Schultze, 1826].
1887 Neritina liturata Eichw. sp. – W. Dybowski: 56–60 [non Schultze, 1826].
1888 [Neritina] liturata Eichw. – W. Dybowski: 79, pl. 2, fig. 10 [non Schultze, 1826].
* 1924 Theodoxus pallasi nom. nov.; Lindholm: 33, 34.
1952 Theodoxus pallasi Lindh. – Zhadin: 208–209, fig. 124.
1969 Theodoxus pallasi Ldh. – Logvinenko & Starobogatov: 343, pl. 5, figs 5–6, textfig. 356.
1994 Theodoxus atrachanicus Starobogatov in Starobogatov et al.: 8–9, fig. 1 (1–2).
1994 Th.[eodoxus] pallasi Ldn. – Starobogatov et al.: 8–9, fig. 1 (3–4).
2006 Theodoxus pallasi Lindholm, 1924. – Kantor & Sysoev: 45, pl. 20, fig. C.
2006 Theodoxus atrachanicus Starobogatov in
2009 Theodoxus pallasi Lindholm, 1924. – Filippov & Riedel: 70, 72, 74, 76, figs 4g–i.
2011 Theodoxus astrachanicus Starobogatov in Starobogatov, Filchakov, Antonova et Pirogov, 1994. – Anistratenko et al.: 54–55, fig. 1 (6).
2012 Theodoxus pallasi Lindholm, 1924. – Welter-Schultes: 29, unnumbered textfig.
2016 Theodoxus (Theodoxus) astrachanicus Starobogatov in
2016 Theodoxus (Theodoxus) pallasi (Lindholm, 1924). – Vinarski & Kantor: 156–157.
2017 Theodoxus pallasi Lindholm, 1924. – Anistratenko et al.: 221, figs 4, 7, 10, 11 [cum syn.].
294 specimens (RGM 1309841, RGM 1309843, RGM 1310190–1310193, LV 201510).
Lectotype: ZIN 54547/63, designated by
“Inter Fucos littoris Derbendensis viva” (living among algae on the shores of Derbent), Dagestan, Russia.
5.95 × 6.62 × 4.81 mm (RGM 1310191, Fig.
Near globular shell with up to 2.7 whorls. Protoconch consists of about half a whorl; diameter of about 570 µm; nucleus measures ca. 250 µm in diameter; surface mostly corroded; P/T transition indistinct, marked by onset of growth lines. Apex weakly raised. Last whorl passes from upper suture over weakly inclined ramp with shallow concavity into broadly, regularly rounded flank that is near semicircular in profile; relative length of ramp increases with ontogeny. Aperture inclined, regularly semicircular. Callus moderately thickened, glossy, edentate; right margin bulging, symmetrically sinuate, with near straight-sided lower and upper thirds and broad, shallow indentation in central third; left margin extends sinuate over base of penultimate whorl, with small adapical indentation, formed by slightly protruding peristome margin. Peristome sharply edged throughout ontogeny from adapical tip to where it passes into callus margin at base of penultimate whorl. Adapically, peristome margin forms steep crest towards callus, sometimes accompanied by thin, shallow furrow at the transition. Color pattern already starts on early teleoconch as widely spaced, dark yellow to brown curved lines, which pass into slightly irregular zigzag lines with partly dichotomizing branches on last whorl; line width, density, amplitude, color and raggedness varies among specimens and partly within the same individual.
The regular, widely spaced zigzag pattern is characteristic of the species. Comparable patterns occur in T. danubialis (Pfeiffer, 1828) and occasionally in T. fluviatilis (Linnaeus, 1758), but in these species lines are finer and more closely spaced. They furthermore differ in their less elongated shells. Similarly, T. euxinus (Clessin, 1886) from the Black Sea is more globular and shows a much denser and finer color pattern (
Theodoxus astrachanicus Starobogatov in
Presently living in the Caspian Sea, the Sea of Azov and the Aral Sea; records from Armenia and the Ural River need confirmation (
The genus Caspia has been widely used for species with small ovoid shells, occasionally with spiral or reticulate teleoconch sculpture. Based on the expression of sculpture, some authors have divided the species among the (sub)genera Caspia s.s., with a single spiral line below the suture, and Clathrocaspia Lindholm, 1930, exposing a reticulate pattern (e.g.,
Ulskia ulskii is available in the present material, and we have investigated the type species of Clathrocaspia (Caspia pallasii Clessin & W. Dybowski in W. Dybowski, 1887) obtained from Holocene deposits of the northern and southern Caspian Sea. However, the type species of Caspia, Caspia baerii Clessin & W. Dybowski in W. Dybowski, 1887, is unknown to us. The original description suggests that it is similar to Ulskia and Clathrocaspia in terms of size and shape, yet to differ in the presence of a single line below to suture, demarcating a narrow subsutural ramp. All three genera are probably closely related, which is also suggested by the similar protoconchs of Ulskia and Clathrocaspia (pers. obs. T.A.N.). Since Ulskia and Clathrocaspia can be easily distinguished based on the presence of sculpture, we propose to treat them as distinct genera. The status of Caspia remains doubtful until the type species is properly re-investigated.
The Caspia–Clathrocaspia–Ulskia species group can be well delimited from the larger, elongate-conical or -ovoid Turricaspia auct. and Pyrgula auct. Moreover, unpublished molecular data suggest that the group is unrelated to Pyrgulinae (T. Wilke, pers. comm. 04/2018). We follow
Caspia ulskii Clessin & W. Dybowski in W. Dybowski, 1887; by original designation. Caspian Sea, Recent.
*1887 Caspia Ulskii nob.; W. Dybowski: 38–39.
1888 [Caspia] Ulskii n. sp. – W. Dybowski: 79, pl. 3, fig. 8.
1952 Caspia ulskii W. Dyb., 1888. – Zhadin: 205, fig. 205.
1969 Pyrgula [(Ulskia)] nana Logvinenko & Starobogatov: 379, fig. 367 (12).
1969 Pyrgula [(Ulskia)] schorygini Logv. et Star. sp. n.; Logvinenko & Starobogatov: 379, fig. 367 (11).
1969 Pyrgula [(Ulskia)] ulskii (Cless. et W. Dyb.). – Logvinenko & Starobogatov: 379, figs 367 (10).
2006 Pyrgula nana Logvinenko et Starobogatov, 1968. – Kantor & Sysoev: 101, pl. 47, fig. D.
2006 Pyrgula schorygini Logvinenko et Starobogatov, 1968. – Kantor & Sysoev: 103, pl. 45, fig. E.
2006 Pyrgula ulskii (Clessin et W. Dybowski in W. Dybowski, 1888). – Kantor & Sysoev: 104, pl. 45, fig. F.
2016 Pyrgula nana Logvinenko et Starobogatov, 1968. – Vinarski & Kantor: 240–241.
2016 Pyrgula schorygini Logvinenko et Starobogatov, 1968. – Vinarski & Kantor: 242.
2016 Pyrgula ulskii (Clessin et W. Dybowski in W. Dybowski, 1888). – Vinarski & Kantor: 244.
19 specimens (RGM 1309790, RGM 1309810, RGM 1309856, RGM 1310208, LV 201506).
“Probable syntype”: ZIN 4608/1. Holotype of P. schorygini: ZIN 4357/1. Holotype of P. nana not traced.
“Kaspi-See” (Caspian Sea, no further details mentioned). Type locality of P. schorygini: Caspian Sea; off Apsheron Peninsula, 40°07.5'N, 50°57.5'E, WGS84, 88 m (after
2.05 × 1.13 mm (RGM 1309810, Fig.
Slender ovoid shell with up to 4.7 whorls. Protoconch broad, low dome-shaped, comprising 1.25 whorls that measure 365 µm; nucleus is ca. 105 µm wide; protoconch surface finely but strongly malleate; pattern irregular on initial part and only partly present on nucleus; P/T transition marked by thin axial line and slight step in the upper suture. Teleoconch whorls slightly ton-shaped, weakly convex in abapical half and straight-sided or almost so in adapical half, followed by pronounced convexity at upper suture, producing slightly stepped spire. Last whorl attains ca. 61–66%, descends into steep, straight base. Aperture slender ovoid, slightly inclined, with faint adapical notch at contact to penultimate whorl. Peristome slightly thickened and expanded. In lateral view, outer lip exposes marked adapical indentation and very weak abapical indentation; columellar lip straight. Umbilicus narrow but always open. Growth lines weak but distinctly sigmoidal, with opisthocyrt upper half and prosocline lower half. In addition, faint spiral threads are visible on some shells.
Pyrgula schorygini Logvinenko & Starobogatov, 1969 and P. nana Logvinenko & Starobogatov, 1969, both of which were also originally included in the subgenus Ulskia, closely resemble this species.
Two more species were attributed to the subgenus Ulskia by
Endemic to the Caspian Sea, reported from water depths between 45 and 120 m (
Andrusovia dybowskii Brusina in Westerlund, 1902a; by original designation. Caspian Sea, Recent.
The subfamily placement of the genus follows
*2000 Andrusovia brusinai Starobogatov, sp. nov.; Starobogatov: 41, fig. 1C.
2006 Andrusovia brusinai Starobogatov, 2000. – Kantor & Sysoev: 83, pl. 40, fig. C.
2016 Andrusovia brusinai Starobogatov, 2000. – Vinarski & Kantor: 214.
39 specimens (RGM 1309839, RGM 1309840, RGM 1310206, LV 201509).
Holotype: ZIN (no number).
Eastern part of the middle Caspian Sea (42°42.5'N, 51°32.5'E, WGS84), at 80 m.
1.52 × 1.44 mm (RGM 1309840, Fig.
Shell broad trochiform, about as high as wide, with up to 4 whorls. Rarely specimens with slightly elevated spire occur. Protoconch high domical, about semicircular in profile; initial part immersed; consists of 1.1 whorls, measures 300 µm in diameter; nucleus about 90 µm wide; protoconch surface finely but strongly malleate near lower suture, rest appears to be irregularly granulate, but that might be due to poor preservation; P/T boundary sharp, marked by massive growth constrictions near lower suture. Teleoconch whorls highly convex, with maximum convexity in adapical half, producing slightly stepped spire. Last whorl attains 74–81% of shell height. Aperture broadly drop-shaped, slightly inclined, with faint adapical notch at contact to penultimate whorl. Peristome slightly thickened and expanded at columella and base; sinuate in lateral view, with weakly protruding central part and weak adapical indentation. Umbilicus wide, deep. Fine prosocline growth lines cover shell. On one specimen, traces of spiral threads occur on base.
The Caspian congeners Andrusovia dybowskii Brusina in Westerlund, 1902a (sensu
Andrusovia brusinai resembles several recent species of Horatia Bourguignat, 1887, Hauffenia Pollonera, 1898 and Islamia Radoman, 1973 in terms of shell shape and protoconch surface. These differ from the present species in the either straight-sided (Hauffenia, Islamia;
Endemic to the Caspian Sea, reported from middle and south Caspian Sea at depths between 47 and 311 m (
Turbo minutus Totten, 1834; by original description. United States, Recent.
cf. * 1887 Hydrobia Grimmi Cless.; W. Dybowski: 55–56.
cf. 1888 [Hydrobia] Grimmi Clessin. – W. Dybowski: 79, pl. 3, fig. 2.
cf. 1952 Hydrobia grimmi (Clessin) W. Dyb., 1888. – Zhadin: 225, fig. 147.
cf. 1969 Pyrgohydrobia grimmi (Cless. et W. Dyb.) – Logvinenko & Starobogatov: 249, fig. 358 (11).
cf. 2006 Caspiohydrobia grimmi (Clessin in W. Dybowski, 1888). – Kantor & Sysoev, 91–92, pl. 43, fig. E.
cf. 2009 Caspiohydrobia grimmi (Clessin et Dybowski, 1888). – Filippov & Riedel: 70–72, 74–76, figs 4a–d.
cf. 2016 Caspiohydrobia grimmi (Clessin et W. Dybowski in W. Dybowski, 1888). – Vinarski & Kantor: 229.
345 specimens (RGM 1309845, RGM 1309847, RGM 1310207, LV 201508).
Not traced.
“Kaspi-See” (Caspian Sea, no further details mentioned).
2.56 × 1.45 mm (LV 201508, Fig.
Shell shape highly variable, ranging from broad ovoid to slender conical, comprising up to 6.5 whorls. Protoconch consisting of about one whorl, with nucleus immersed; initial part slightly raised, producing acute apex; surface weakly granular to malleate; P/T transition clear. Protoconch and teleoconch whorls highly convex, sometimes slightly flattened centrally in later whorls; suture deep. Size of last whorl varies between 55–62%, descends into straight-sided base. Aperture regularly ovoid, slightly inclined, touching base of penultimate whorl, leaving wide umbilicus. Peristome simple, sometimes weakly expanded. Surface smooth expect for very fine prosocline growth lines.
The shells of Ecrobia can only be reliably identified on the species-level using molecular data (
Most of the species presently assigned to Caspiohydrobia Starobogatov, 1970, including its type species, Pyrgohydrobia eichwaldiana Golikov & Starobogatov, 1966, range within the morphological variability of this species. Previous examination of both reproductive systems (
W. Dybowski (1887: 7) noted that all diagnoses were drafted by Clessin and himself and most new species were therefore marked with “nob.” (Lat. nobis, “us”). However, W. Dybowski obviously made exceptions. In case of the new genus Clessinia, he marked the authority with “m.” (Lat. meus, “mine”). For Hydrobia grimmi, the authority is clearly indicated with “Cless.”, making Clessin the sole author of the species (unlike indicated by several authors).
Caspian Sea; Lake Sawa, Iraq (
1882 Pyrgulinae Brusina: 230.
1914 Micromelaniidae B. Dybowski & Grochmalicki: 276.
1915 Turricaspiinae B. Dybowski & Grochmalicki: 103.
2017 Pyrgulinae Brusina, 1882. – Bouchet et al.: 212, 346 [cum syn.].
The Caspian Pyrgulinae (sensu lato) encompasses 64 species that are considered accepted in the current literature (
In addition to the problems associated with distinguishing species, genus-level classification is poorly resolved as well. Several attempts have been made to categorize this vast variability, and genus concepts have changed tremendously (e.g., B.
A thorough revision of all Caspian Pyrgulinae is beyond the scope of this study, but we discuss and revise the concepts that have been applied to the species studied herein.
Turricaspia B. Dybowski & Grochmalicki, 1915 (type species: Micromelania turricula B. Dybowski & Grochmalicki, 1915) was introduced for species with turriform, elongate shells with numerous whorls. Presently, the genus includes 22 Caspian species, encompassing elongate and broad, conical and ovoid, and sculptured and smooth species (
Some of the species classified as Turricaspia by
Based on a review of the Pontocaspian species formerly attributed to these genera and illustrated in the literature (
Clessiniola species can be easily distinguished from species attributed to other genera based on their broad shells with a large body whorl and aperture. The situation for the Laevicaspia–Caspiella–Euxinipyrgula is more difficult. The three type species (see above) share the ovoid shape with cyrtoconoid spire, the high whorl accretion rate, the shape, inclination, lateral sinuation and thickening of the aperture, and the extent and sculpture of the protoconch (e.g.,
The ovoid shape, lateral sinuation and thickening of the aperture typical for the Laevicaspia–Caspiella–Euxinipyrgula group are also found among species of the genus Prososthenia Neumayr, 1969 from the middle Miocene of the Dinaride Lake System (e.g.,
Species of Turricaspia differ from Laevicaspia in the slower, regular whorl accretion, producing a conical spire and a higher number of whorls at the same size. In addition, Turricaspia species have usually more fragile shells, thinner peristomes and often more strongly sinuate growth lines.
The genus Caspia is listed among Pyrgulinae in latest catalogues (
Finally, several Pontocaspian Pyrgulinae have been previously assigned to the genus Micromelania Brusina, 1874 (e.g., W. Dybowski 1887, B.
1887 Clessinia W. Dybowski: 41 [non Doering, 1875].
1924 Clessiniola Lindholm: 32–33, 34.
1928 Clessinola Strand: 68 [junior objective synonym of Clessiniola].
Paludina variabilis Eichwald, 1838; by typification of replaced name (Clessinia W. Dybowski, 1887). Volga delta and Caspian Sea, Quaternary to Recent.
*1838 Paludina variabilis m.; Eichwald: 151–152.
1841 Paludina variabilis m. – Eichwald: 253–254, pl. 38, figs 6–7.
1853 Pal.[udina] variabilis m. – Eichwald: 285.
1887 Clessinia variabilis Eichw. sp. – W. Dybowski: 41–42.
1888 [Clessinia] variabilis Eichw. sp. – W. Dybowski: 79, pl. 2, fig. 6.
1952 Clessiniola variabilis (Eichwald, 1841). – Zhadin: 255, fig. 199.
1966 P.[yrgula] (Clessiniola) variabilis. – Golikov & Starobogatov: 356, fig. 2 (2).
1969 Pyrgula [(Clessiniola)] variabilis (Eichw.) – Logvinenko & Starobogatov: 377, fig. 367 (1).
1987 T.[urricaspia] variabilis (Eichw.). – Alexenko & Starobogatov: 34, fig. 5.
2006 Turricaspia variabilis (Eichwald, 1838). – Kantor & Sysoev: 111, pl. 49, fig. J.
2011 Turricaspia variabilis (Eichwald, 1838). – Anistratenko et al.: 85, fig. 3 (15).
2014 Turricaspia variabilis. – Taviani et al.: 4, fig. 3b.
2016 Turricaspia variabilis (Eichwald, 1838). – Vinarski & Kantor: 251.
4867 specimens (RGM 1309815, RGM 1309826, RGM 1309827, RGM 1309831, RGM 1310243–1310247, LV 201507).
Not traced.
“In Volgae ostio prope Astrachanum, et versus mare Caspium; etiam fossili in calcatio lapide conglutinato recentissimo Dagesthanici littoris” (at the Volga river mouth near Astrakhan, and towards the Caspian Sea; also in recently lithified fossil limestone at the shores of Dagestan).
5.91 × 3.31 mm (LV 201507, Fig.
Broadly drop-shaped to rarely conical shell of up to six whorls. Protoconch insufficiently preserved to specify extent and surface sculpture; P/T transition indistinct; first whorl measures ca. 340 µm in diameter. Teleoconch whorls moderately and regularly convex; sometimes, spire is very faintly stepped; suture narrow. In many specimens, shells starts to grow stronger in abapical direction in course of last (two) whorl(s), producing non-parallel suture and relatively higher penultimate whorl. Rarely, forms with comparatively slender shape and regularly increasing whorls (and thus relatively smaller last and penultimate whorls) occur. Both types are linked via intermediates. Aperture regularly ovoid, inclined; inner lip glossy, weakly to sometimes more prominently thickened; strongly adnate, sheet-like expanded over base of penultimate whorl and columella, rarely leaving very narrow umbilicus; broad, shallow spout occurs at transition between columella and base; outer lip mainly thin, sometimes weakly thickened at anterior notch. Growth lines very faint, with prosocline upper third and near orthocline lower two-thirds.
This species displays a large morphological variability within our ample material. Shell shape ranges between slender conical to broadly ovoid, sometimes with weakly irregular growth. Likewise, shell size, whorl convexity, and number of whorls vary considerably. Yet, these features intergrade without clear boundary, rendering a distinction of species unreasonable.
The morphological variability is not restricted to our material but a general feature of Clessiniola. It was documented by several previous authors, partly for specimens from the same localities (e.g.,
Because of the fluent morphological transition between forms traditionally referred to as C. variabilis, C. triton and C. martensii, as well as their joint occurrence in several localities in the Pontocaspian region, one might consider all of them synonymous. Personal observations on Holocene material from Dagestan area, however, indicate indeed distinguishable morphotypes without intermediates. Moreover, frequent shell repair found in most of the Selitrennoye specimens additionally complicates an unbiased view on morphological diversity. A more in-depth investigation comparing undamaged material from different sites is thus required.
Given the large variability, the Caspian species Clessiniola ovum (Logvinenko & Starobogatov, 1969) and C. trivialis (Logvinenko & Starobogatov, 1969), as well as C. pseudotriton (Golikov & Starobogatov, 1966) from the Dniester River mouth (compare
Clessinia ahngeri Westerlund, 1902 is often listed as junior synonym of C. variabilis, but without discussion (e.g.,
The record of “Paludina Eichwaldi Kryn.”
Endemic to the Pontocaspian region. Found in the Caspian Sea and the lower courses of rivers and freshwater parts of the Azov and Black seas (
? 1902a Thaumasia Westerlund: 104 [non Perty, 1833; non Albers, 1850].
1917 LaevicaspiaB. Dybowski & Grochmalicki: 5.
1928 Caspiella Thiele: 353, 381.
1999 Euxinipyrgula Sitnikova & Starobogatov: 158, 162.
Rissoa caspia Eichwald, 1838; by subsequent designation by
*1838 Rissoa caspia m.; Eichwald: 154–155.
1841 Rissoa caspia – Eichwald: 256–257, pl. 38, figs 14–15.
1853 Riss.[oa] caspia m. – Eichwald: 273.
non 1876 Hydrobia caspia, Eichw. – Grimm: 150–153, pl. 6, fig. 15.
non 1877 Hydrobia caspia, Eichw. – Grimm: 79–80, pl. 7, figs 3a–d.
non 1887 Micromelania caspia Eichw. sp. – W. Dybowski: 21.
non 1888 Micr.[omelania] caspia Eichw. sp. – W. Dybowski: 78, pl. 1, fig. 1.
? 1896 B.[uliminus] (Napaeus?) goebeli Westerlund: 188.
1914 Micromelania (?) curta Nalivkin: 21–22, 31, pl. 6, figs 1–2 [partim; non figs 3–4, 7, 9–14].
1914 [Micromelania (?) curta] var. plano-convexa Nalivkin: 22, 31, pl. 6, figs 15–18.
non 1914 Micromelania caspia Eichw. – Nalivkin: 22, 31, pl. 6, figs 5–6 [partim; non fig. 8].
non 1917 Micromelania (Turricaspia, Laevicaspia) caspia Eichw. – B. Dybowski & Grochmalicki: 5–8, 36–38, pl. 1, figs 1–3.
non 1969 Pyrgula caspia (Eichw.). – Logvinenko & Starobogatov: 369–370, fig. 364 (1).
1987 T.[urricaspia] caspia (Eichw.). – Alexenko & Starobogatov: 33, fig. 2.
2006 Turricaspia caspia (Eichwald, 1838). – Kantor & Sysoev: 106, pl. 49, fig. M.
2014 Euxinipyrgula lincta. – Taviani et al.: 4, fig. 3c [non Micromelania lincta Milashevich, 1908].
2016 Turricaspia caspia (Eichwald, 1838). – Vinarski & Kantor: 246.
300 specimens (RGM 1309788, RGM 1309789, 1309797, RGM 1309798, RGM 1310196, RGM 1310257, RGM 1310258, LV 201511).
Lectotype: ZIN (No. 1 in systematic catalogue), designated by
“In eodem lapide calcario Dagesthanico, fossilis” (in the same limestone of Dagestan [referring to the previous species, also found in Dagestan], fossil).
9.01 × 3.31 mm (RGM 1310257, Fig.
Large, slender ovoid shell comprising up to 8.3 whorls. Protoconch large, measuring 535–600 µm at 1.15–1.2 whorls, with initial part inflated; nucleus almost immersed, 190–230 µm wide; nucleus and early protoconch bear intentions of malleate sculpture, which passes into granular surface after half a whorl accompanied by onset of spiral striae; P/T boundary indistinct. Whorl convexity decreasing rapidly: first teleoconch whorl moderately convex, second to last whorl low convex, sometimes almost straight-sided; maximum convexity is in lower half; whorls closely attached, suture narrow; a very small but marked convexity appears at upper suture, producing a faintly stepped spire; occasionally, it is accompanied by shallow abapical concavity. Last whorl makes up 46–50% of shell height, passing over regular but weakly convex to near straight-sided to slightly concave base. Aperture slender ovoid, inclined, closely attached to preceding whorl; in latest ontogeny, shell growth is more abapically directed, resulting in marked thickening at adapical tip. Peristome simple, thin, slightly expanded and indented at base; distinctly and regularly sigmoidal in lateral view, with upper half broadly indented and lower half broadly protruding; inner lip protrudes in lateral view, extending sheet-like over base of penultimate whorl; umbilicus mostly closed, rarely very narrow, slit-like. Growth lines weakly sigmoidal: strongly prosocline in upper half, weakly opisthocline in lower half. Several specimens show faint spiral threads on last and penultimate whorls.
Different concepts of this species previously applied have led to considerable confusion about its real identity. This is partly rooted in the description and illustration provided by
Micromelania caspia sensu
Similarly, Pyrgula caspia sensu
The similar Laevicaspia iljinae (Golikov & Starobogatov, 1966) from Holocene deposits of the Crimean Peninsula can be distinguished in its more slender shape and the spruce-like whorl outline (i.e., steep, straight-sided upper two-thirds passing over convexity into flatter, convex lower third; see also
Endemic to the Caspian Sea (
*1859 Rissoa cincta; Abich: 57, pl. 2, fig. 6.
?1887 Caspia Orthii Clessin & W. Dybowski in W. Dybowski: 40.
?1888 [Caspia] Orthii n. sp. – W. Dybowski: 79, pl. 3, fig. 6.
1969 Pyrgula [(Caspiella)] cincta (Abich). – Logvinenko & Starobogatov: 372, fig. 366 (4).
2006 Pyrgula cincta (Abich, 1859). – Kantor & Sysoev: 98, pl. 47, fig. L.
2016 Pyrgula cincta (Abich, 1859). – Vinarski & Kantor: 236.
174 specimens (RGM 1309806, RGM 1309807, RGM 1310200, LV 201514).
Not traced.
3.83 × 1.93 mm (LV 201514, Fig.
Slender ovoid shell with up to 6.5 whorls. Protoconch broad, low dome-shaped, consists of 1.2 whorls that measure 415 µm in diameter, with slightly inflated initial part; nucleus 150 µm wide; protoconch surface weakly granulate, with intentions of striae on second half; P/T transition distinct, formed by sharp, thin axial line. Whorl convexity decreases steadily during ontogeny, with early teleoconch whorls being moderately convex and penultimate and last whorl low convex to almost straight-sided. On third teleoconch whorl, weak subsutural band emerges that slightly enhances during ontogeny; band forms weak bulge throughout, with maximum convexity in its lower half and steep, almost straight-sided ramp in upper half; abapical demarcation clear, sometimes accompanied by thin groove. Last whorl attains 54–65% of shell height, passing from flattened whorl flank over marked convexity into steep, straight-sided base. Aperture near drop-shaped, inclined, with acute adapical angle, straight parietal margin, obtuse angle between parietal and columellar margins, sometimes slightly expanded palatal margin. Peristome not thickened, weakly expanded at columella and base; regularly sinuate in lateral view, with broad adapical indentation and about equally broad and high abapical protrusion. Umbilicus closed or very narrow. Growth lines weakly prosocline in upper half, near orthocline in lower half.
The Selitrennoye specimens match with the original description in terms of size (shell height: 3–4 mm), the ovoid shell shape, the number of whorls, the rounded last whorl and the simple peristome margin; they differ in the expression of the subsutural band, which Abich indicated to be “weakly keeled”. We consider these differences to range within the intraspecific variability of this species.
Laevicaspia cincta can be readily distinguished from other Pontocaspian Pyrgulinae by its ovoid, slightly stepped shell with broad, blunt apex, subsutural band and flattened whorls in later ontogeny. Laevicaspia abichi (Logvinenko & Starobogatov, 1969) from the middle Caspian Sea, differs in the much larger size (6.8 × 3 mm), the conical shape, the narrower subsutural band and the larger aperture. The Caspian endemic species Laevicaspia kowalewskii (Clessin & W. Dybowski in W. Dybowski, 1887) resembles L. cincta very closely in terms of the slender ovoid shape with near straight-sided whorls, the closely attached aperture with thin peristome, and the lacking umbilicus; it differs in the lack of a subsutural band and the more elongate shape.
Caspia orthii Clessin & W. Dybowski in W. Dybowski, 1887 was synonymized with the present species by previous authors (e.g.,
Note that Rissoa cincta Deshayes, 1861 (p. 404, pl. 24, figs 4–6), described from the Eocene (Bartonian) of the Paris Basin, is a junior primary homonym of this species and thus invalid. At present, this species is classified in the genus Pseudotaphrus Cossmann, 1888 (
Endemic to the Caspian Sea, in the southern part at a depth of >250 m (
*1838 Rissoa Conus m.; Eichwald: 155.
1841 Rissoa Conus m. – Eichwald: 257, pl. 38, figs 16a–b [wrongly given as “figs 16–17” on p. 257; see also corrigendum at the end of Eichwald’s work].
1853 Riss.[oa] conus m. – Eichwald: 273.
non 1876 Eulima conus, Eichw?. – Grimm: 154–156, pl. 6, fig. 14.
1887 Nematurella conus Eichw. sp. (non Grimm). – W. Dybowski: 45.
1888 [Nematurella] conus Eichw. sp. – W. Dybowski: 78, pl. 2, fig. 3.
? 1896 Prosostenia [sic] conus Eichw. – Sinzov: 49–50, pl. 1, figs 30–33.
1926 ?Nematurella conus (Eichwald). – Wenz: 2007.
1952 Caspiella conus (Eichwald, 1841). – Zhadin: 259, fig. 211.
1969 Pyrgula [(Caspiella)] conus (Eichw). – Logvinenko & Starobogatov: 374, fig. 366 (5–6).
non 2006 Turricaspia conus conus (Eichwald, 1838). – Kantor & Sysoev: 106, pl. 48, fig. J.
2016 Turricaspia conus conus (Eichwald, 1838). – Vinarski & Kantor: 246–247.
1135 specimens (RGM 1309828, RGM 1309829, RGM 1309830, RGM 1310199, RGM 1310226–1310228, LV 201515).
Not traced.
“In eodem lapide calcareo, fossilis” (in the same limestone [referring to previous species, found in Dagestan], fossil).
5.14 × 2.19 mm (RGM 1309830, Fig.
Ovoid, glossy shell with up to 6.8 whorls. Shell outline variable, depending on growth stage: shells with up to 5 whorls are rather broad, nearly conical; in late ontogeny, shell growth is directed adapically, producing more elongate shapes with narrow, high last whorl; sometimes, these slender elongate morphotypes have slightly irregular shape. Protoconch consists of 1.2 whorls with 355 µm in diameter; nucleus almost immersed, 125 µm wide; surface faintly malleate or granulate, with intentions of spiral sculpture detected in some specimens; P/T boundary very distinct, marked by sharp, thin axial line. Teleoconch whorls weakly to moderately convex, sometimes adapically flattened. Last whorl attains between 55–63% of total height, grades into straight-sided or weakly convex base. Aperture drop-shaped, inclined, closely attached to base of preceding whorl, usually covering or rarely leaving slit-like umbilicus. Peristome slightly expanded, thin or thickened all around, especially at adapical tip; regularly sinuate in lateral view, with broad adapical indentation and about equally broad and high abapical protrusion. Growth lines weak, prosocline in upper half, orthocline in lower half.
The holotype of L. kolesnikoviana illustrated by
The species has affinities with several representatives of the Azov and Black seas. Pyrgula (Caspiella) lindholmiana Golikov & Starobogatov, 1966, today considered as a subspecies of L. conus (e.g.,
“Eulima conus Eichwald” as described and illustrated by
The illustrations of specimens from the Kuyalnikian (late Pliocene to early Pleistocene) of the Odessa region identified as Prososthenia conus by
Endemic to the Caspian Sea, reported from depths between 0 and 120 m (
*1966 P.[yrgula] (Caspiella) kolesnikoviana Logvinenko et Starobogatov; Golikov & Starobogatov: 357, fig. 2 (8–9).
1969 Pyrgula [(Caspiella)] kolesnikoviana Logv. et Star. – Logvinenko & Starobogatov: 372, fig. 366 (1).
2006 Pyrgula kolesnikoviana Logvinenko et Starobogatov in Golikov et Starobogatov, 1966. – Kantor & Sysoev: 100, pl. 47, fig. N.
2016 Pyrgula kolesnikoviana Logvinenko et Starobogatov in Golikov et Starobogatov, 1966. – Vinarski & Kantor: 239.
514 specimens (RGM 1309816, RGM 1309818, RGM 1309819, RGM 1310212, RGM 1310221–1310225, LV 201516).
Holotype: ZIN 4462/1.
Caspian Sea, N of Apsheron peninsula, NW from Kamni Dva Brata Island, 40°47'N, 49°42'E, 30 m (
3.55 × 1.63 mm (RGM 1309816, Fig.
Pyrgulinae. A–C, K Laevicaspia kolesnikoviana (Logvinenko & Starobogatov in Golikov & Starobogatov, 1966), RGM 1309816 D L. kolesnikoviana, LV 201516 E, N L. kolesnikoviana, RGM 1309819 F, G Laevicaspia vinarskii sp. n., holotype, LV 201517 H, O L. vinarskii sp. n., RGM paratype, 1309805 I, J, L, M L. vinarskii sp. n., paratype, RGM 1309821.
Small, slender ovoid, shiny shell with up to 6.9 whorls. Protoconch consists of 1.2 whorls, measuring 355 µm in diameter; nucleus rather long, ca. 130 µm wide; surface finely granulate (maybe due to preservation; traces of finely malleate to irregularly striate pattern occurs on margins of nucleus and initial part); faint striae on last third; P/T boundary distinct. Whorl convexity of teleoconch whorls decreasing: first to second whorl moderately to highly convex, last whorl low to moderately convex. Faint subsutural band appears on later teleoconch whorls in some specimens, sometimes accompanied by weak concavity below. Last whorl attains 50–57% of shell height, passing via broad, regular convexity in to weakly convex base. Aperture ovoid, inclined, closely attached to preceding whorl; in latest ontogeny, shell growth is more abapically directed, resulting in marked thickening at adapical angle. Peristome thin or thickened all around, with parietal margin sometimes slightly expanded; weakly but regularly sinuate in lateral view, with broad adapical indentation and about equally broad and high abapical protrusion. Umbilicus usually closed or very narrow, slit-like. Growth lines weak, prosocline in upper half, orthocline in lower half. In addition, faint spiral furrows appear in some specimens.
Co-occurring Laevicaspia vinarskii sp. n. differs in the consistently lower whorl expansion rate at the same size and the smaller aperture. Laevicaspia kowalewskii (Clessin & W. Dybowski in W. Dybowski, 1887) can be distinguished by its broader and larger shell.
Endemic to the Caspian Sea, reported from depths between 25 and 180 m (
Holotype: LV 201517; 3.70 × 1.72 mm (Fig.
5 specimens (RGM 1309793, LV 201732).
Selitrennoye, Astrakhan, Russia; northern Caspian Basin; GPS coordinates: 47°10'21.19"N, 47°26'25.41"E (WGS84).
Early Late Pleistocene (late Khazarian, MIS 5).
In honor of Maxim Vinarski (Saint Petersburg State University) for his contributions to Malacology.
Slender ovoid, imperforate shell with up to 6.5 moderately convex whorls, narrow suture, granulate–striate protoconch, high whorl expansion rate and small, adnate, inclined aperture.
Slender ovoid shell with up to 6.5 whorls. Protoconch consists of 1.2 whorls measuring 375 µm; nucleus is 140 µm wide; surface strongly granulate on nucleus, less so on remaining protoconch, striae appear on last 0.25 whorls; P/T transition marked by distinct growth rim. Teleoconch whorls moderately convex, separated by narrow suture; whorls increase slowly in height, with the last attaining 53–57% of shell height, passing into weakly convex base. Weak subsutural band is observed in one specimen. Aperture small, inclined, closely attached to base of preceding whorl, leaving no or slit-like umbilicus. Peristome slightly thickened, especially at adapical tip; regularly sinuate in lateral view, with broad adapical indentation and about equally broad and high abapical protrusion. Distinct spiral furrows occur in well preserved specimens. Growth lines weak, prosocline in upper half, orthocline in lower half.
The new species differs from co-occurring Laevicaspia kolesnikoviana in the higher whorl expansion rate at about the same size and the larger aperture. Laevicaspia ? ismailensis (Golikov & Starobogatov, 1966) from lakes Yalpug and Kugurlu in the Danube river delta is more slender and larger (5.6 mm) at the same number of whorls and has a less inclined, rounder aperture (see holotype illustrated by
Endemic to the Caspian Sea Pleistocene, so far only known from Selitrennoye.
1915 Turricaspia B. Dybowski & Grochmalicki: 105.
1917 Trachycaspia B. Dybowski & Grochmalicki: 22.
1969 Pyrgula (Caspiopyrgula) Logvinenko & Starobogatov: 366.
1969 Pyrgula (Eurycaspia) Logvinenko & Starobogatov: 357.
1969 Pyrgula (Oxypyrgula) Logvinenko & Starobogatov: 366.
Micromelania turricula B. Dybowski & Grochmalicki, 1915; by subsequent designation by Wenz (1939). Caspian Sea, Recent.
*1915 Micromelania (Turricaspia) Andrussowi nov. sp.; B. Dybowski & Grochmalicki: 125–126, pl. 3, figs 31a–b.
1917 Micromelania (Turricaspia, Trachycaspia) Andrussowi nov. sp. – B. Dybowski & Grochmalicki: 26–27, pl. 4, fig. 39.
1969 Pyrgula [(Turricaspia)] andrusovi [sic] (Dyb. et Gr.). – Logvinenko & Starobogatov: 365–366, fig. 362 (4) [partim].
2006 Turricaspia andrussowi (B. Dybowski et Grochmalicki, 1915). – Kantor & Sysoev: 104–105, pl. 48, fig. A [partim].
2016 Turricaspia andrussowi (B. Dybowski et Grochmalicki, 1915). – Vinarski & Kantor: 245 [partim].
3 spire fragments (RGM 1309814, RGM 1310205).
Lectotype: ZIN 4355/1 (specimen illustrated by B.
Caspian Sea (no locality specified).
Available fragments indicate very slender, conical shell. Apex broad, blunt, bulbous. Whorl profile flattened, very weakly spruce-like, with straight-sided upper two-thirds passing over convexity into weakly convex lower third; in addition, broad, flat subsutural band appears, sometimes accompanied by very narrow concavity below. Umbilicus seems fully closed. Aperture not preserved in any specimen.
The identification of the three spire fragments rests upon the strongly adpressed whorls with very narrow suture and the flattened, spruce-like whorl profile, and the large, bulbous protoconch. Turricaspia eulimellula (B. Dybowski & Grochmalicki, 1915) has a similarly slender spire with adpressed whorls, but it bears a basal keel and the maximum whorl convexity is around mid-height instead of in the lower third. Turricaspia grimmi (Clessin & W. Dybowski in W. Dybowski, 1887) differs in its perfectly straight-sided, rectangular, very weakly stepped whorl profile (see also B.
A very similar species is Pyrgula dubia Logvinenko & Starobogatov, 1969 from the middle Caspian Sea, matching the present one in the weakly spruce-like whorl profile; in fact, it might just be a juvenile specimen of T. andrussowi. Similarly, Pyrgula turkmenica Logvinenko & Starobogatov, 1969, from the eastern part of southern Caspian Sea, corresponds to T. andrussowi in the weak subsutural band accompanied by an abapical concavity; it might as well be a juvenile representative of T. andrussowi.
Endemic to the Caspian Sea (
?*1838 Rissoa dimidiata m.; Eichwald: 156.
? 1841 Rissoa dimidiata m. – Eichwald: 258, pl. 38, figs 17a–b [wrongly given as “figs 16–17” on p. 258; see also corrigendum at the end of Eichwald’s work].
? 1853 Pal.[udina] dimidiata m. – Eichwald: 285–286.
? 1887 Micromelania dimidiata Eichw. sp. – W. Dybowski: 31 [partim].
? 1888 Micromelania dimidiata Eichw. sp. – W. Dybowski: 78, pl. 1, figs 4a–f, 5 [partim].
? 1917 Micromelania (Turricaspia) dimidiata Eichw. – B. Dybowski & Grochmalicki: 32–33, pl. 4, figs 44–47 [partim].
? 1969 Pyrgula dimidiata (Eichw.). – Logvinenko & Starobogatov: 358–359, fig. 359 (1).
? 2006 Pyrgula dimidiata (Eichwald, 1838). – Kantor & Sysoev: 99, pl. 46, fig. K.
? 2016 Pyrgula dimidiata (Eichwald, 1838). – Vinarski & Kantor: 238.
1 subadult specimen (RGM 1309787).
Not traced.
“In eodem lapide calcareo, fossilis” (in the same limestone [referring to the previous species, found in Dagestan], fossil).
4.29 × 1.93 mm.
Slender elongate shell with ca. 6.5 whorls preserved. Protoconch granulate, originally perhaps densely malleate. First teleoconch whorl straight-sided in profile, passing into weakly convex outline on 2nd–3rd whorl. Between 3rd and 4th whorl, broad, blunt central swelling emerges, grading into thin angulation on 5th whorl; no keel is developed. Whorl portion above swelling/angulation straight-sided, below weakly convex; directly above it, weak concavity is formed locally. Aperture ovoid, strongly adnate, leaving no umbilicus, with thin peristome. Growth lines rather distinct, with prosocline upper half and near orthocline lower half.
A single subadult shell containing ca. 6.5 whorls (including the protoconch) is available. Size and number of whorls as well as the centrally placed angulation correspond well to
Endemic to the Caspian Sea, reported from middle and south Caspian Sea at depths between 35 and 200 m (
*1915 Micromelania (Turricaspia) spica var. lyrata nov. var.; B. Dybowski & Grochmalicki: 117, pl. 2, fig. 18.
1915 Micromelania (Turricaspia) spica var. incisata nov. var.; B. Dybowski & Grochmalicki: 117, pl. 2, fig. 19.
1915 Micromelania (Turricaspia) spica var. striata nov. var.; B. Dybowski & Grochmalicki: 117, pl. 2, fig. 20.
1917 Micromelania (Turricaspia) spica var. lyrata nov. var. – B. Dybowski & Grochmalicki: 17, pl. 3, fig. 25.
1917 Micromelania (Turricaspia) spica var. incisata nov. var. – B. Dybowski & Grochmalicki: 18, pl. 3, fig. 26.
1917 Micromelania (Turricaspia) spica var. striata nov. var. – B. Dybowski & Grochmalicki: 18, pl. 3, fig. 27.
1969 Pyrgula [(Turricaspia)] lirata [sic] (Dyb. et Gr.). – Logvinenko & Starobogatov: 365, fig. 362 (2).
2006 Pyrgula lirata [sic] (B. Dybowski et Grochmalicki, 1915). – Kantor & Sysoev: 101, pl. 46, fig. E.
2016 Pyrgula lirata [sic] (B. Dybowski et Grochmalicki, 1915). – Vinarski & Kantor: 240.
562 specimens (RGM 1309802, RGM 1309825, RGM 1310209, RGM 1310213, RGM 1310214, RGM 1310216, RGM 1310218–1310220, LV 201512, LV 201513).
Lectotype: ZIN 4552/1 (specimen illustrated by B.
Caspian Sea (no locality specified).
7.68 × 2.59 mm (RGM 1310213, Fig.
Slender elongate shell of up to 9 whorls. Protoconch large, measuring about 485 µm in diameter; it forms bulbous cap on top of shell and comprises 1.25 whorls; surface weakly granulate, with striae on last 0.25 whorls; nucleus low, broad, ca. 170 µm in diameter; P/T transition very distinct, marked by sharp growth cessation. Teleoconch whorls low to moderately convex, often flattened or with straight-sided upper half, which creates spruce-like morphology. Sometimes, very weak and thin bulge appears below suture, producing faintly stepped spire. Most shells bear very low and somewhat irregular spirals, but expression varies considerably concerning its onset (mainly starts on lower whorls), strength (faint traces to distinct but blunt keels) and number of elements (one keel near base to several keels spread across whorl profile). Expression of sculpture varies in most specimens throughout ontogeny, which creates uneven, rugged appearance. Aperture comparatively small, in most cases regularly ovoid and weakly inclined, covering up umbilicus entirely or leaving very thin opening; peristome simple. Growth lines strongly sigmoidal, with prosocline upper third and opisthocline lower two-thirds.
This species can be distinguished from its congeners in its large, bulbous protoconch and the typical, somewhat irregular sculpture. It is consistently larger, more massive and on average bears much stronger sculpture than co-occurring T. ? spica. The varieties “Micromelania (Turricaspia) spica var. incisata” and “M. (T.) spica var. striata” introduced by B.
Endemic to the Caspian Sea (after
*1865 Bythinia Meneghiniana, Issel; Issel: 21, pl. 1, figs 12–13.
1866 Bythinia Meneghiniana, Issel. – Issel: 405, pl. 1, figs 12–13.
1917 Micromelania (Turricaspia) caspia var. inflata nov. var. – B. Dybowski & Grochmalicki: 9, pl. 1, fig. 5.
? 1969 Pyrgula caspia (Eichw). – Logvinenko & Starobogatov: 369–370, fig. 364 (1).
? 1969 Pyrgula meneghiniana (Issel). – Logvinenko & Starobogatov: 370, fig. 365 (2).
non 1987 T.[urricaspia] meneghiniana meneghiniana (Iss.). – Alexenko & Starobogatov: 35, fig. 8.
2006 Turricaspia meneghiniana (Issel, 1865). – Kantor & Sysoev: 109, pl. 49, fig. E.
2016 Turricaspia meneghiniana (Issel, 1865). – Vinarski & Kantor: 248.
248 specimens (RGM 1309799, RGM 1309800, RGM 1310197, RGM 1310198, RGM 1310256, LV 201518).
Not traced.
“Nei giacimenti fossiliferi di Baku” (from fossil deposits in Baku).
10.86 × 4.27 mm (RGM 1310256, Fig.
Conical shell with up to 9.3 whorls. Protoconch comprises 1.3 whorls, measuring 440 µm in diameter, with slightly inflated initial part; nucleus measures 150 µm in diameter; entire protoconch surface weakly granulate; indistinct spiral striae appear on second half; P/T transition distinct, formed by sharp, thin axial line. Teleoconch whorls increase slowly but regularly in height and width; whorls moderately convex, whereas convexity slightly decreases with ontogeny. Last whorl attains 45–48% of shell height, passes over perfect convexity into slightly convex base. Aperture ovoid, inclined, closely attached to base of preceding whorl across almost entire parietal margin. Peristome thin, not thickened, little expanded; weakly sigmoidal in lateral view, with broad, shallow indentation in upper half and broad, weak protrusion in lower half; inner lip protrudes in lateral view, extending sheet-like over base of penultimate whorl; umbilicus very narrow, slit-like. Growth lines weakly sigmoidal: strongly prosocline in upper half, weakly opisthocline in lower half. Several specimens show faint spiral threads on last and penultimate whorls.
Our material matches well to the description of
Micromelania subulata Westerlund, 1902 is commonly listed as junior synonym of this species but always without discussion (e.g.,
Another commonly cited synonym is Micromelania caspia var. inflata B. Dybowski & Grochmalicki, 1915, which indeed matches both Issel’s description and our material.
Turricaspia meneghiniana differs from the similarly large Laevicaspia caspia (Eichwald, 1838) in its regularly conical profile, the higher number of whorls, and the higher whorl convexity. The drawings of “Pyrgula meneghiniana (Issel)” provided by
Endemic to the Caspian Sea, reported from middle and south Caspian Sea at depths between 0 and 35 m (
*1915 Micromelania (Turricaspia) caspia var. pulla nov. var.; B. Dybowski & Grochmalicki: 111, pl. 1, fig. 6a.
1917 Micromelania (Turricaspia) caspia var. pulla nov. var. – B. Dybowski & Grochmalicki: 10, pl. 1, fig. 7.
1969 Pyrgula [(Turricaspia)] pulla (Dyb. et Gr.). – Logvinenko & Starobogatov: 361–362, fig. 360 (8).
2006 Pyrgula pulla (B. Dybowski et Grochmalicki, 1915). – Kantor & Sysoev: 102, pl. 46, fig. C.
2016 Pyrgula pulla (B. Dybowski et Grochmalicki, 1915). – Vinarski & Kantor: 242.
186 specimens (RGM 1309803, RGM 1309804, RGM 1309820, RGM 1310211, RGM 1310253–1310254, LV 201519).
Lectotype: ZIN 4422/1 (specimen illustrated by B.
Caspian Sea (no locality specified).
4.88 × 2.10 mm (LV 201519, Fig.
Slender conical shell with up to 8 whorls. Protoconch bulbous, weakly granulate, with striae on second half; diameter 410 µm, consists of 1.25 whorls; nucleus low, broad, 140 µm wide; transition to teleoconch distinct. Teleoconch whorls weakly convex, with maximum convexity at or slightly below midline of whorl profile; portion above maximum convexity almost straight-sided, portion below weakly convex. Whorls are separated by deep suture. Height of last whorl amounts 45% of total shell. Sometimes intentions of spiral lines appear on lower half of last whorl. Aperture ovoid, oblique, with weakly thickened and slightly expanded peristome; in lateral view, peristome is distinctly sigmoidal, with broad, shallow indentation in upper half and broad, weak protrusion in lower half. Umbilicus very narrow or closed. Growth lines sigmoidal, markedly prosocline in upper half, weakly opisthocline in lower half.
The species can be easily distinguished from most other species of Turricaspia by its comparably broad conical shape, the low-convex whorls, and its small size. Juvenile specimens of T. meneghiniana remind of T. pulla but the former have broader shells with more convex whorls. Turricaspia pullula is likewise broader and exposes a characteristic tripartite whorl profile (see below).
Endemic to the Caspian Sea, reported from middle and south Caspian Sea at depths between 15 and 75 m (
*1915 Micromelania (Turricaspia) caspia var. pullula nov. var.; B. Dybowski & Grochmalicki: 111–112, pl. 1, fig. 7.
1917 Micromelania (Turricaspia) caspia var. pullula nov. var. – B. Dybowski & Grochmalicki: 10–11, pl. 1, fig. 8.
1969 Pyrgula [(Turricaspia)] pullula (Dyb. et Gr.). – Logvinenko & Starobogatov: 366–367, fig. 363 (3).
2006 Turricaspia pullula (B. Dybowski et Grochmalicki, 1915). – Kantor & Sysoev: 109, pl. 50, fig. B.
2016 Turricaspia pullula (B. Dybowski et Grochmalicki, 1915). – Vinarski & Kantor: 249.
1 damaged specimen (RGM 1310210).
Lectotype: ZIN 4423/1 (specimen illustrated by B.
Caspian Sea (no locality specified).
5.36 × 2.62 mm.
A single incomplete specimen of about 6 whorls is preserved. Protoconch is corroded beyond recognition. Early teleoconch whorls are poorly convex to centrally flattened. Convexity strongly increases on about 3rd whorl. From 4th whorl onwards, whorl surface is partitioned into three zones: two lower zones are roughly straight-sided in profile, upper one slightly concave; middle zone slightly wider than other two; zones are separated by blunt angulations, whose expression varies between very faint to distinct (but no keel is formed). Aperture not preserved, but the tight coiling of the last preserved whorl suggests that umbilicus is absent. Growth lines strongly prosocline in upper third, near orthocline in lower two-thirds; transition coincides with boundary between upper and middle zone.
The available specimen corresponds well to the lectotype as illustrated by
Endemic to the Caspian Sea, reported from the western part of the middle Caspian Sea at a depth of 60 m (
? *1855 Paludina spica m.; Eichwald: 303–304, pl. 10, figs 8–9.
? 1887 Micromelania spica Eichw. sp. – W. Dybowski: 29–31.
? 1888 Micr.[omelania] spica Eichw. sp. – W. Dybowski: 78, pl. 1, figs 6a–c, pl. 3, figs 11a–d.
? 1917 Micromelania (Turricaspia) spica Eichw. – B. Dybowski & Grochmalicki: 16–17, pl. 3, figs 22–27.
? 1952 Micromelania spica (Eichwald, 1855). – Zhadin: 252–253, fig. 194.
? 1992 Turricaspia spica. – Anistratenko & Prisyazhniuk: 19, fig. 2d.
? 2006 Turricaspia spica (Eichwald, 1855). – Kantor & Sysoev: 110, pl. 49, fig. F.
? 2009 Turricaspia cf. spica (Eichwald, 1855). – Filippov & Riedel: 70, 72, 74, 76, figs 4e–f.
? 2016 Turricaspia spica (Eichwald, 1855). – Vinarski & Kantor: 250.
1420 specimens (RGM 1309784, RGM 1309785, RGM 1309786, RGM 1309811, RGM 1309812, RGM 1309813, RGM 1310229–1310231, RGM 1310233–1310237, RGM 1310239, RGM 1310240, LV 201501, LV 201502).
Not traced, most probably in ZIN (
“Im kapischen Meere, am Ufer der Insel Tschetschnja, vorzüglich nLittorinimorphastwärs von der Insel im Meeresgrunde” (in the Caspian Sea, at the shores of Ostrov Chechen’, especially on the seafloor northeast of the island).
6.40 × 2.18 mm (RGM 1310237, Fig.
Pyrgulinae. A–CTurricaspia ? spica (Eichwald, 1855), form B, RGM 1310237 D–FT. ? spica, transitional form, LV 201501 G–IT. ? spica, form B, LV 201502 J–LT. ? spica, form A, RGM 1310230 M–OT. ? spica, form B, RGM 1310231 PT. ? spica, form A, RGM 1310233 QT. ? spica, transitional form, RGM 1310236 RT. ? spica, RGM 1309813.
Slender elongate shell, with up to nine convex whorls. Protoconch forms small bulbous cap, consisting of 1.3 whorls that measure 365 µm in diameter; surface weakly granulate, spiral striae set in after 0.5 whorls; nucleus is 140 µm wide; P/T boundary marked by thin, sharp axial line. Early teleoconch whorls have low convex profile. Two morphotypes are present: form A is broader, with whorls increasing slightly more in height (thus producing relatively larger last whorl) and little convex whorls; form B is more slender, whorls increase less fast in height in relation to width and whorl profile is stronger and more regularly convex. Both types are linked via intermediates. Generally, whorl profile varies between regularly convex (of varying strength), laterally flattened or bipartite (with near straight-sided upper half and convex lower half; rarely, transition between halves coincides with spiral thread). Suture is narrow. In some specimens, last whorl is slightly inflated and aperture is expanded. Traces of spiral sculpture, ranging from faint lines to blunt keels of variable number occur on several shells. Aperture expansion and sculpture are found on both morphotypes, as well as in intermediates. Umbilicus mostly covered by inner lip; if open, it is very narrow. Growth lines markedly sigmoidal, with prosocline upper third and opisthocline lower two-thirds.
The huge morphological variability with intergrading morphotypes complicates reasonable taxonomic distinctions within this taxon. Moreover, much of the shape variation (especially in later whorls) seems to be a result of shell repair after predator-induced damage.
The variability also hampers linking our material to an existing name. Several species (and varieties) have been introduced for slender elongate, multi-whorled shells from the Caspian Sea. While the sculptured representatives can be fairly well delimited, the smooth-shelled taxa have caused considerable confusion. Particularly challenging are the many small, slender species with pointy apex, moderately to strongly convex whorls and thin peristome. The group includes (aside from T. spica): T. elegantula (Clessin & W. Dybowski in W. Dybowski, 1887), T. turricula (B. Dybowski & Grochmalicki, 1915), T. nossovi (Kolesnikov, 1947), T. concinna (Logvinenko & Starobogatov, 1969), T. spasskii (Logvinenko & Starobogatov, 1969), T. uralensis (Logvinenko & Starobogatov, 1969) and T. astrachanica (Pirogov, 1971). Turricaspia lyrata (B. Dybowski & Grochmalicki, 1915), which was originally introduced as subspecies of T. spica, can be well delimited from that group because of its much larger, blunt apex.
A major problem in identifying and discriminating those species is that the concepts applied by later authors occasionally diverge largely from the original perceptions. This especially regards T. spica and the species described by B.
The identity of Turricaspia spica (sensu Eichwald) is dubious. The original description and illustration do not allow distinction from other similar species. The present specimens differ slightly from T. spica sensu Kantor & Sysoev, 2006, which is characterized by a faster whorl accretion rate and relatively higher whorls (including the last whorl). In contrast, our material largely fits the concept of T. spica as used by B.
Turricaspia spica is endemic to the Caspian Sea. After
Paludina exigua Eichwald, 1838; by original designation. Caspian Sea, Pleistocene.
The genus Abeskunus and the species that have been attributed to it have caused considerable confusion. A detailed discussion of the taxonomic and nomenclatural problems associated with Abeskunus, considerations on its systematic placement, as well as a description of the type species will be provided in a forthcoming study. Preliminary work confirms classification of the species described below in Abeskunus.
*1887 Zagrabica Brusiniana nob.; W. Dybowski: 52–53.
1888 Zagrabica Brusiniana n. sp. – W. Dybowski: 79, pl. 2, fig. 7.
1952 Zagrabica brusiniana W. Dyb., 1888. – Zhadin: 235, fig. 166 [partim].
1969 Pseudamnicola [(Abeskunus)] brusiniana (Cless. et W. Dyb.). – Logvinenko & Starobogatov: 381, fig. 367 (15).
2006 Pseudamnicola brusiniana (Clessin et W. Dybowski in W. Dybowski, 1888). – Kantor & Sysoev: 114, pl. 51, fig. J.
2016 Pseudamnicola brusiniana (Clessin et W. Dybowski in W. Dybowski, 1888). – Vinarski & Kantor: 222.
489 specimens (RGM 1309834, RGM 1309842, RGM 1310194, LV 201505).
Not traced.
“Kaspi-See” (Caspian Sea, no further details mentioned).
4.12 × 3.82 mm (RGM 1309834, Fig.
Shell broadly conical, comprising up to 4.5 whorls. Protoconch broadly domical, with almost immersed initial part; consists of 1.25 whorls, measures 525 µm in diameter; nucleus is ca. 160 µm wide; nucleus surface covered with irregular elongated wrinkles; protoconch surface wrinkled, bearing thin, irregular spiral grooves on first third, passing over irregular pattern of faint spiral grooves and wrinkles into numerous, regularly parallel spiral furrows on last third; P/T transition without growth rim, marked by onset of growth lines. Teleoconch whorls highly convex, with maximum convexity in adapical half, producing slightly stepped spire. Last whorl attains 77–85% of shell height. Aperture drop-shaped, slightly inclined, with marked adapical notch at contact to penultimate whorl. Outer peristome margin not or slightly thickened, columellar and parietal margins weakly thickened; peristome slightly expanded towards columella (protruding towards umbilicus in lateral view) and strongly towards base; weakly sinuate in lateral view, with broad but weak adapical protrusion and straight-sided abapical part. Umbilicus narrow, slit-like. Prosocline growth lines cover shell surface.
The species differs from the type species A. exiguus (Eichwald, 1838) in the conical shell, the taller spire, the less inflated last whorl, and the distinct umbilicus. Abeskunus brusinianus michelae Tadjalli-Pour, 1977 is much more globular than A. brusinianus. The latter species strongly reminds of and might be conspecific with A. exiguus. Pseudamnicola depressispira Logvinenko & Starobogatov, 1969, which these authors also included in the subgenus Abeskunus, differs from the presumed congeners in the valvatoid shape with very wide umbilicus and small but distinct riblets.
Pseudamnicola ? brusiniana Pavlović, 1903 is a junior secondary homonym of this species, for which
Endemic to the Caspian Sea, in the southern and middle part at a depth of >250 m (
In addition to the Pontocaspian elements, six taxa including ubiquitous Palearctic species were identified. They all occur in low numbers and differ from Pontocaspian species in their preservation state. Shells of larger taxa (Valvata, Esperiana, and Lithoglyphus) are eroded and suggest transport. The smaller planorbids are better preserved but differ in their orange color indicating that they were not deposited along with the whitish shells of the Pontocaspian residents. Moreover, all six taxa are typical freshwater dwellers (e.g.,
Anisus cf. spirorbis (Linnaeus, 1758) (Fig.
Planorbis cf. planorbis (Linnaeus, 1758) (Fig.
Bithynia sp. (Fig.
Esperiana esperi (Férussac, 1823) (Fig.
Lithoglyphus naticoides (Pfeiffer, 1828) (Fig.
Valvata piscinalis (Müller, 1774) (Fig.
Non-indigenous species. A–DAnisus cf. spirorbis (Linnaeus, 1758), LV 201503 E–FA. cf. spirorbis, RGM 1309801 G–IPlanorbis cf. planorbis (Linnaeus, 1758), LV 201504 J–LP. cf. planorbis, RGM 1309835 M Bithynia sp., juvenile, RGM 1309853 N Esperiana esperi (Férussac, 1823), RGM 1309792 O Lithoglyphus naticoides (Pfeiffer, 1828), RGM 1309832 P Valvata piscinalis (Müller, 1774), RGM 1310249. Scale bar equals 1 mm unless indicated otherwise. Note that all Planorbidae are figured at the same scale to facilitate comparison.
The current work provides a first insight into the magnitude of endemic Caspian gastropod biodiversity. The gastropod fauna of Selitrennoye is composed of 24 species, 16 of which are Pontocaspian endemic species and 15 exclusively Caspian. Six species are considered to be non-indigenous based on the combination of a truly freshwater autecology, a general wide spread palearctic distribution and a slightly different preservation from the bulk of the well preserved Caspian lacustrine species in the material. The non-Caspian gastropods are low in numbers, and we suspect they may have either floated into the Caspian Sea during periods of high river discharge or, more likely, were mixed in from underlying sediment layers through bioturbation. The Selitrennoye fauna was deposited in open lacustrine settings at a paleosalinity of approximately 10–11 psu as suggested by the general composition of the mollusk fauna (Yanina 2012). The presence of paired bivalves in the same sample indicates the in-situ character of the fauna. The shelly levels are located around 17 m b.s.l., and late Khazarian maximum sea levels are estimated as 10 m b.s.l. The presence of very sandy sediments with lenses suggests deposition above storm wave base. Altogether, this might translate into a sea floor at about 7 m water depth. The settings can be best compared with the present-day southermost part of the northern Caspian Basin.
The taxonomy and systematics of Caspian gastropods is very much in need of an update. The abundant and well-preserved material presented here has given an indication about the generic placements of species and the magnitude of species richness. When compared to the latest inventory of Caspian gastropods by
The present revision does elucidate generic concepts. Even though it is open for further improvement, it will provide a basis for the establishment of evolutionary relationships within genera by comparison with older (Bakunian/Apsheronian) and younger Caspian faunas. By understanding species richness and evolutionary relationships of Caspian faunas, we will be able to document the nature and severity of the Anthropocene biodiversity crisis in this long-lived lake.
List of species recovered from the late Khazarian deposits at Selitrennoye, with indication of their status as endemic to the Caspian Sea and the Pontocaspian region as a whole.
Species | Family | No. of specimens | Caspian endemic | Pontocaspian endemic |
---|---|---|---|---|
Theodoxus pallasi Lindholm, 1924 | Neritidae | 294 | ||
Ulskia ulskii (W. Dybowski & Clessin in W. Dybowski, 1888) | Hydrobiidae | 19 | x | x |
Andrusovia brusinai Starobogatov, 2000 | Hydrobiidae | 39 | x | x |
Ecrobia cf. grimmi (Clessin in W. Dybowski, 1888) | Hydrobiidae | 345 | ||
Clessiniola variabilis (Eichwald, 1838) | Hydrobiidae | 4867 | x | |
Laevicaspia caspia (Eichwald, 1838) | Hydrobiidae | 300 | x | x |
Laevicaspia cincta (Abich, 1859) | Hydrobiidae | 174 | x | x |
Laevicaspia conus (Eichwald, 1838) | Hydrobiidae | 1135 | x | x |
Laevicaspia kolesnikoviana (Logvinenko & Starobogatov in Golikov & Starobogatov, 1966) | Hydrobiidae | 514 | x | x |
Laevicaspia vinarskii sp. n. | Hydrobiidae | 9 | x | x |
Turricaspia andrussowi (B. Dybowski & Grochmalicki, 1915) | Hydrobiidae | 3 | x | x |
Turricaspia ? dimidiata (Eichwald, 1838) | Hydrobiidae | 1 | x | x |
Turricaspia lyrata (B. Dybowski & Grochmalicki, 1915) | Hydrobiidae | 562 | x | x |
Turricaspia meneghiniana (Issel, 1865) | Hydrobiidae | 248 | x | x |
Turricaspia pulla (B. Dybowski & Grochmalicki, 1915) | Hydrobiidae | 186 | x | x |
Turricaspia pullula (B. Dybowski & Grochmalicki, 1915) | Hydrobiidae | 1 | x | x |
Turricaspia ? spica (Eichwald, 1855) | Hydrobiidae | 1420 | x | x |
Abeskunus brusinianus (W. Dybowski & Clessin in W. Dybowski, 1888) | Hydrobiidae | 489 | x | x |
Valvata piscinalis (Müller, 1774) | Valvatidae | 8 | ||
Esperiana esperi (Férussac, 1823) | Melanopsidae | 1 | ||
Bithynia sp. | Bithyniidae | 4 | ||
Lithoglyphus naticoides (Pfeiffer, 1828) | Lithoglyphidae | 1 | ||
Anisus cf. spirorbis (Linnaeus, 1758) | Planorbidae | 13 | ||
Planorbis cf. planorbis (Linnaeus, 1758) | Planorbidae | 3 |
FPW and TY conducted field work and collected the material; SV and FPW processed the material; TAN, SV, and FPW identified the species; TAN and FPW wrote the manuscript.
We are grateful to Vitaliy V. Anistratenko, Maxim Vinarski, Jan Johan ter Poorten, Anita Eschner, and Yuri Kantor for support during literature research. Maxim Vinarski is moreover thanked for inspection of the collection catalogue of the Zoological Institute of the Russian Academy of Sciences in St. Petersburg. We thank Ronald Pouwer and Marjan Helwerda for assistance in sample sorting. Our sincere thanks also go to Dietrich Kadolsky, Mathias Harzhauser, Peter Glöer, Diana Delicado, and Daniela Esu for sharing taxonomic considerations. Tom Wilke shared information on unpublished molecular data of the Caspian hydrobiids. Ted von Proschwitz and Anna Persson are thanked for their effort in trying to locate Westerlund’s type material. Thomas Nichterl helped with Latin translations. The careful reviews by Vitaliy V. Anistratenko and Frank Riedel greatly improved the quality of this work. This paper contributes to the PRIDE Project (“Drivers of Pontocaspian Biodiversity Rise & Demise”) funded by the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 642973. It also contributes to the FreshGEN Project (“Freshwater systems in the Neogene and Quaternary of Europe: Gastropod biodiversity, provinciality, and faunal gradients”) funded by the Austrian Science Fund FWF (project no. P25365-B25). T.A.N. was supported by an Alexander-von-Humboldt Scholarship and a Martin Fellowship granted by Naturalis Biodiversity Center. T.Y. was supported by the Russian Science Foundation (grant no. 16-17-10103).
After
B.
The publication date of Birshtein et al.’s comprehensive systematic account of the Caspian fauna, including the catalogue of Caspian mollusks by Logvinenko and Starobogatov, is usually given as “1968” and so it says in the book itself. According to