Research Article |
Corresponding author: Ümit Kebapçı ( kebapci@gmail.com ) Academic editor: Robert Hershler
© 2015 Mehmet Zeki Yıldırım, Ümit Kebapçı, Seval Bahadır Koca, Arzu Yüce.
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:
Yıldırım MZ, Kebapçı Ü, Bahadır Koca S, Yüce A (2015) New Bythinella (Gastropoda, Bythinellidae) species from western Turkey. ZooKeys 481: 1-13. https://doi.org/10.3897/zookeys.481.8225
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Bythinella anatolica sp. n., Bythinella istanbulensis sp. n., Bythinella magdalenae sp. n., and Bythinella wilkei sp. n. from western Turkey are described herein. Illustrations of the shell and genitalia of the newly described taxa, together with comparisons with previously known Bythinella taxa and a key to the species from western Turkey, are also provided.
Bythinella , new species, freshwater, springs, Turkey
Bythinella Moquin-Tandon, 1856, the sole genus of the caenogastropod family Bythinellidae (
Bythinella contains 132 species and subspecies (
In the present study, four new Bythinella species are described from western Turkey based on field surveys between 2006 and 2013. These species are discriminated based on details of shell morphometry, head and cephalic tentacle pigmentation, penial appendix, tubular gland, female genitalia, central tooth of radula and operculum. A comparison with other species and an identification key to other congeners described from Turkey are also presented.
Specimens were collected by hand-netting and preserved in 75% ethanol. Dissections and measurements of the genital organs and the shells were carried out using a Olympus SZ12 stereo microscope; photographs were taken with a digital camera system. Morphological terminology largely follows
Abbreviations: SW: shell width, SH: shell height, rs: reseptaculum seminis, ah: aperture height, aw: aperture width, Coll. Yıldırım: Collection of M. Zeki Yıldırım in Zoological Museum of the Mehmet Akif University (Burdur, Turkey).
Bulimus viridis Poiret, 1801.
(Coll. Yıldırım): SH 2.78 mm, SW 1.67 mm, ah 1.22 mm, aw 1.11 mm. Coll. Yıldırım; TURKEY, Manisa, Çırpıcıdede hill on Spil Mountain, N 38°44.66', E 27°24.30', 17. 07. 2006. Leg. M. Z. Yıldırım. Paratypes: 18 ex. (5 dissected), same data and locality as holotype in Coll. Yıldırım.
A spring below Çırpıcıdede hill on Spil Mountain and its small outflow stream down the hill, Manisa.
Named after Anatolia.
Shell thin, usually cylindrical-ovoid (SW/SH 57.19%), appearing blackish (owing to darkly pigmented animal), with slightly rough surface; apex blunt, depressed on the left side; having 3 1/2–4 very tumid whorls (more convex the left side), last whorl more inflated, sutures deep. Aperture ovoid or pear shaped, height of the aperture usually greater than penultimate whorl, umbilicus relatively broad and deep, sometimes covered by the outer lip, palatal lip margin not reflected, columellar and parietal margins broadly reflected.
Head black; tentacles unpigmented. Operculum oval and with distinct growth lines.
Penis unpigmented and variable in natural position among individuals (straight to bent or folded), though not in shape. Tubular gland thickened, penial appendix usually very short (varying according to the shell size of the individuals). Bursa copulatrix narrow and elongated, rs1 large and globular in shape. Central tooth of radula with 9 pointed cusps, 1 median and 4 each on sides; lateral margin without any cusps, but undulated; basal lip roundish (Figures
Measurements (n=19): SH: 2.79 mm (min 2.37/max 3.07), SW: 1.65 mm (min 1.37/max 1.92), SH/SW: 1.7 (min 1.59/max 1. 91), SW/SH: 0.58 (min 0.52/max 0.62), ah/SH: 0.44 (min 0.41/max 0.46).
Differential diagnosis: Identified by its larger shell (except B. wilkei sp. n.) and ear–like aperture having reflected margins, a character state not observed in other Turkish species.
Specimens were collected from under the stones in the spring outflow down the hill.
The new species is distinguished from other Turkish species by its larger shell dimensions and ear like shell aperture. Bythinella turca
According to our current knowledge of Peri-Aegean Bythinella species, the area of the Aegean coast of Turkey is a center of diversity for the genus. The Eastern Aegean Islands Ikaria, Kos, Lesbos, and Chios are inhabited by B. kosensis (
Bythinella opaca, Schütt, H., 1965 Zur Systematik und Ökologie Türkischer Süsswasserprosobranchier. Zoologische Mededelingen, 41: 43–71. (misidentification).
Bythinella “opaca”, Schütt, H., 1980 Zur Kenntnis griechischer Hydrobiiden, Arch.Moll.110 (4/6):115.
Bythinella sp. A,
(Coll. Yıldırım): Shell height: 2.74 mm, width 1.43 mm (Coll. M.Z. Yıldırım); TURKEY, Istanbul, Bahçeköy, a small spring at the entrance of Bahçeköy in Belgrad Forest, N41°11.09', E28°59.5', 23.02.2013, leg. A. Yüce. Paratypes: 27 ex., same data and locality as holotype; 5 ex. Zoologisches Museum Hamburg (ZMH 79661), 5 ex. Naturhistorisches Museum in Wien (NHMW 109174), rest in the Coll. Yıldırım. Additional material: 5 ex. in the University of Giessen (Coll. Prof. Wilke), rest in the Coll. Yıldırım (5 dissected).
A small spring at the entrance of Bahçeköy in Belgrad Forest, Bahçeköy, Istanbul.
Named after the type locality.
Shell broad cylindrical oval, yellowish horn-colored, surface smooth and glossy covered by a thick, solid and rough encrustation due to chemical conditions of the spring water; apex blunt; 3½–4 convex whorls, rapidly and regularly increasing to form a cylindrical shape, last whorl about 2/3 of the shell height, sutures relatively deep; aperture pear-shaped, height nearly the same as or slightly less than the penultimate whorl, columellar margin with an distinct inner lip reaching basal and apical corners of the aperture; operculum orange, umbilicus narrow and slit-shaped (Figs
Tubular gland relatively short and thick. Pallial roof unpigmented, head having little pigmentation (Fig.
Measurements (n=28): SH: 2.67 mm (min 2.18/max 2.87), SW: 1.66 mm (min 1.37/max 1.94), SH/SW: 1.61 (min 1.39/max 1.84), SW/SH: 0.62 (min 0.54/max 0.72), ah/SH: 0.41 (min 0.37/max 0.50).
This new species is distinguished from other Turkish Bythinella species by its nearly cylindrical shell with broad and blunt apex. Small and attached rs1, unpigmented and light coloured pallial roof are the other key characters.
Specimens were collected from the stones in a small spring and its pond.
Based on shell characters only,
Despite the conchological similarities, the new species is anatomically distinct from the Central European species B. austriaca and B. opaca. While the lighter pallial roof colouration is also observed in Bythinella opaca (Glöer & Pešic, 2006), B. austriaca has a dark pallial roof colouration. The new species differs from both of these taxa in having a very short and broad penial appendix (cf. long trumpet-shaped penial appendix in these species).
(Coll. Yıldırım): SH 2,5 mm, SW 1,62 mm, ah 1,12 mm, aw 1,06 mm; TURKEY, Aydın, İncirliova, Karagözler Village, Karapınar spring above the village, 37°57,796'N, 27°49,375'E, leg. S. Bahadır Koca. Paratypes: 17 ex in Coll. Yıldırım, same data and locality as holotype; 18 ex in Coll. Yıldırım, TURKEY, Aydın, İncirliova, Karagözler Village, Çaycuk spring above the village, 37°57,829'N, 27°49,230'E, leg. S. Bahadır Koca.
Karapınar Spring, Karagözler Village, İncirliova, Aydın.
Named after the late Polish malacologist Magdalena Szarowska (1952–2013), who contributed greatly especially to the knowledge of the Balkan Truncatelloidea.
Shell ovate-conical and with 3–3,5 whorls. Apex truncated. Last whorl slowly increasing and broader than previous whorls, sutures not deep and periphery nearly flat. Aperture roundish oval. Umbilicus small, hollow shaped and covered by the lip. Operculum nucleus along left margin, oval shaped and with distinct growth lines.
Head having little amount of pigmentation, rather concentrated on the tips of the tentacles and around the mouth. Tentacles slightly longer than snout. Penis unpigmented, tapering towards the tip, tip not very pointed at its distal end, club-shaped. Tubular gland externally visible, thin, elongated and convoluted. Bursa copulatrix narrow and elongated, rs1 globular in shape. Central tooth of radula with 9 pointed cusps, 1 median and 4 each on sides; lateral margin without any cusps, but undulated.
Measurements: Karapınar Spring (n=18): SH: 2.55 mm (min 2.19/max 2.91), SW: 1.64 mm (min 1.37/max 1.78), SH/SW: 1.55 (min 1.42/max 1.72), SW/SH: 0.65 (min 0.58/max 0.70), ah/SH: 0.45 (min 0.44/max 0.46). Çaycuk Spring (n=18): SH: 2.41 mm (min 2.06/max 2.78), SW: 1.59 mm (min 1.31/max 1.87), SH/SW: 1.52 (min 1.37/max 1.66), SW/SH: 0.66 (min 0.64/max 0.67), ah/SH: 0.46 (min 0.46/max 0.48).
Bythinella magdalenae sp. n. is distinguished from B. cosensis
Specimens were collected from two small, closely proximal seepage springs.
Çaycuk Spring is very close to the type locality, thus indeed B. magdalenae sp. n. can be considered a single spot endemic as in the case of other species known from Turkey.
(Coll. Yıldırım): SH 2.75 mm, SW 1.84 mm, ah 1.28 mm, aw 1.12 mm; TURKEY, Kocaeli, Maşukiye, spring along the road to Kartepe, 40°40.603'N, 30°08.605'E, leg. S. Bahadır Koca. Paratypes: 29 ex in Coll. Yıldırım, same data and locality as holotype.
Spring along the road to Kartepe, Maşukiye, Kocaeli.
Named after the malacologist Thomas Wilke (Justus Liebig University, Germany).
Shell oval conical, light brown, but appearing blackish due to encrustation; having 3–3.5 tumid whorls; last whorl slowly increasing and broader than previous whorls, sutures deep. Apex blunt. Aperture roundish oval, last whorl strongly descending towards aperture and aperture projected forward, lip in some individuals having a small protuberance in upper palatal margin. Umbilicus small, hollow or completely covered by the lip. Operculum ovate, translucent and with distinct growth lines.
Head having little pigmentation, pigment rather concentrated on bases of the tentacles and around mouth. Tentacles short and broad. Unpigmented penis tapering towards the tip, tip not pointed at its distal end; tubular gland thick and with two convolutions. Bursa copulatrix narrow and elongated, rs1 elongate. Central tooth of radula with 9 pointed cusps, 1 median and 4 each on sides; lateral margins lacking cusps, but undulated.
Measurements (n=22): SH: 2.80 mm (min 2.56/max 3.03), SW: 1.88 mm (min 1.56/max 2.19), SH/SW: 1.50 (min 1.31/max 1.68), SW/SH: 0.66 (min 0.60/max 0.76), ah/SH: 0.47 (min 0.41/max 0.51).
Excluding B. anatolica sp. n. described from Manisa Province, Bythinella wilkei sp. n. has a larger shell than other Turkish congeners. The nearly circular aperture, which is strongly descending and projected forward, is also characteristic of the new species.
The specimens were collected from the outflow of a small spring having little vegetation and a gravel substrate.
The species is one of the two northernmost distributed congeners in Turkey. Unlike B. istanbulensis sp. n. the new species is found in higher altitudes.
1 | Shell having 3.5–4 whorls | 2 |
– | Shell having 3–3.5 whorls | 4 |
2 | Shell elongated oval, aperture margins reflected | Bythinella anatolica |
– | Shell nearly cylindrical, aperture margins not reflected | 3 |
3 | Pallial roof black, penis shorter than penial appendix | B. kazdaghensis |
– | Pallial roof light coloured, penis longer than penial appendix | B. istanbulensis |
4 | Tubular gland thin, long and convoluted (more than 2 loops) | 5 |
– | Tubular gland thick, short and less convoluted | B. wilkei |
5 | Shell oval, SH<2.3 mm | B. occasiuncula |
– | Shell ovate-conic and usually SH>2.3 mm | 6 |
6 | Periphery almost straight, sutures shallow, tentacles longer than proboscis | B. magdalenae |
– | Periphery convex, sutures deep, tentacles shorter than proboscis | B. turca |
Map showing the locations of Bythinella species in Turkey and the Eastern Aegean Islands: Bythinella anatolica sp. n. (black triangle), B. istanbulensis sp. n. (closed square), B. kazdaghensis (diamond), B. kosensis (asterix), B. magdalenae sp. n. (closed circle), B. occasiuncula (open circle), B. turca (open triangle), B. wilkei sp. n. (open square).
We thank Eike Neubert (Naturhistorisches Museum der Burgergemeinde Bern) for revising of the first version of the manuscript and MSc student Estée Bochud for photography.