Review Article |
Corresponding author: Enrico Ruzzier ( enrico.ruzzier@uniroma3.it ) Academic editor: Patrice Bouchard
© 2024 Enrico Ruzzier, Andrea Di Giulio.
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:
Ruzzier E, Di Giulio A (2024) Taxonomic considerations of selected Western Palaearctic Mordellidae Latreille, 1802 (Coleoptera, Tenebrionoidea). ZooKeys 1207: 151-165. https://doi.org/10.3897/zookeys.1207.119398
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The present contribution is devoted to the review of some species of Mordellidae belonging to the Italian fauna described by Mariano Zuccarello Patti and Mario Enrico Franciscolo. New taxonomic combinations are proposed: Mediimorda argyropleura (Franciscolo, 1942), comb. nov., Mordella quomoi Franciscolo, 1942, comb. rev., and Mordellokoiles grandii Franciscolo, 1942, stat. nov. Mediimorda argyropleura, Mordella quomoi and Mordellokoiles grandii are considered species that are not part of the Italian fauna. In addition, given the impossibility of identifying the species based on its original description and the destruction of type material, Mordella aradasiana Patti, 1840 is treated as nomen dubium.
Biodiversity, faunistic, Italy, synonymy
Mordellidae Latreille, 1802, also commonly known as tumbling flower beetles, are members of the rather diverse beetle family that comprises more than 2000 extant species worldwide. This group is notoriously taxonomically complicated due to the great uniformity of species and the fact that some characters have not always been consistently and uniquely applied; this is particularly true for the Western Palaearctic, and Europe in particular, where the great richness in sibling and cryptic species has resulted in high taxonomic productivity as well as increasing difficulty in recognizing species (e.g.
The purpose of this contribution is to review some mordellid taxa described by Mariano Zuccarello Patti and Mario Enrico Franciscolo in order to clarify the identity and assess status of these taxa.
All the material considered in this contribution belongs to the collections of the
Museo Civico di Storia Naturale “G. Doria”, Genoa, Italy (
Measurements are abbreviated in the text as follows: EL, elytral length from scutellar apex to elytral apices along suture;
EW, maximum elytral width at humeri;
HL, head length from anterior clypeal margin to occipital carina along midline;
HpygL, maximum hypopygidial length;
HW, maximum head width;
PL, pronotal length along midline;
PW, maximum pronotal width;
PygL, maximum pygidial length;
TL, sum of head, pronotal, elytral, and pygidial lengths. Wing venation terminology follows that of
The morphological study was carried out using an Olympus SZX 16 stereomicroscope. Images were taken with a Visionary Digital LK Lab System (Visionary Digital, Palmyra, VA, USA) equipped with a Canon EOS 6D mark II dSLR camera and an MP-E 65mm f/2.8 1–5× lens (Canon, Tokyo, Japan). Stack images were produced using Helicon Focus v. 7.
Mordella argyropleura Franciscolo, 1942b: 18.
Mordella argyropleura
:
Variimorda (Variimorda) argyropleura:
Falsopseudotomoxia argyropleura
:
Holotype
, male, labeled “Isola di Capraia, Toscana, S. Rocco, C. Mancini, Giglio, VI.1930 // Olo-Typus // Mordella argyropleura n. sp. (handwritten)” (
Conservation state: state of preservation discreet, left antenna broken, partially missing. The left paramere is damaged and missing the long external branch.
12 exx labeled “Somalia IT. Jach Sciumo (Giuba): 1923, S. Patrizi lg. // Mediimorda argyropleura E. Ruzzier det. 2024” (
Mordella argyropleura was known to this day exclusively by its type material (
Given this latest finding and given the fact that the type of M. argyropleura appears to be prepared on the same kind of paper board as the Somali specimens, we consider the locality of the species described by Franciscolo to be the result of a labeling error, and, therefore, M. argyropleura should be excluded from the Italian fauna.
Having already had the opportunity to review the type material of M. argyropleura (Fig.
Mediimorda argyropleura (Franciscolo, 1942). Holotype of Mordella argyropleura Franciscolo, 1942 A right paramere and A’ left paramere; male specimen from Jach Sciumo (Giuba, Somalia) B right paramere and B’ left paramere; male specimen from southern Italy (localities given by
The assignment of Mordella argyropleura to Falsopseudotomoxia Ermisch, 1954 by
Mordella aradasiana Patti, 1840: 292.
The identity of M. aradasiana remains, and will remain, unsolved. The species was described in 1840 by Sicilian amateur naturalist Mariano Zuccarello Patti based on a single specimen he collected in the locality “Praja” (eastern coast of Sicily, between Catania and Agnone Bagni) (
Based on the scant information provided (e.g., the size and color pattern), it is impossible to assign the species to any Italian and, more generally, circum-Mediterranean mordellid species; in addition, some of the characters provided in the description, such as the occipital part of the head partially covering the pronotum and the elytra not completely covering the wings underneath, would seem to suggest a taxon belonging to Macrosiagon Hentz, 1830 (Ripiphoridae Gemminger, 1870), the female of Macrosiagon meridionalis (Costa, 1859) in particular. Unfortunately, some of the chromatic elements, such as the red spots on the elytra, a character not observed in any Italian Macrosiagon, do not allow us to attribute M. aradasiana to the latter taxon with certainty.
The quality of the descriptions, as well as the validity of the species described by Patti, have already been widely criticized and in many cases disavowed by several authors (e.g.,
It is also exceedingly important to note that the type of M. aradasiana, like the entire Patti collection inclusive of other taxa he described, was lost or destroyed (
Mordella quomoi Franciscolo, 1942a: 7.
Mordella cuomoi Franciscolo, 1942b: 22 (subsequent unjustified emendation).
Variimorda (Variimorda) quomoi:
Variimorda (Variimorda) quomoi
(Franciscolo, 1951 [sic!]):
Holotype
(by monotypy), male, labeled “Is. Giglio, II.1902. G. Doria // Typus // Mordella Quomoi Franciscolo (handwritten)// Mordella quomoi Francisc. det. M.E. Franciscolo” (
Conservation state: modest, antennae and anterior tarsomeres broken, partially missing.
Measurements. HL: 1.0 mm; HW: 1.5 mm; PL: 1.3 mm; PW: 1.9 mm; EL: 3.3 mm; EW: 1.8 mm; PygL: 1.6 mm; HpygL 0.8 mm; TL: 7.2 mm.
Color.
General color of the integument dark brown to black, except for the epistoma, mouthparts, palps, and anterior and middle legs which are orange-amber colored (Fig.
Head.
Head transverse in dorsal view (1.6× as wide as long), sub-hemispheric in lateral view with the highest point in correspondence to the occiput (3B); occipital margin almost straight in dorsal view (Fig.
Prothorax. Pronotum trapezoid in dorsal view, 1.4× as wide as long, widest slightly before middle, moderately convex in lateral view; pronotal disc microreticulate, densely covered with recumbent and posteriorly oriented setae, punctures larger and more impressed than those on head. Anterior margin of the pronotum gently and gradually curved, and the anterior angles curved downward, resulting in not being visible in dorsal view. Central lobe of the posterior margin of the pronotum markedly protruding posteriad. Anterior and posterior angles of the pronotum obtuse in lateral view; lateral margins of pronotum gently curved in dorsal view, and straight in lateral view. Profemora and protibia gently but markedly curved dorso-ventrally; tarsomeres subcylindrical, truncate at apex.
Pterothorax. Scutellum triangular, with a broadly rounded apex; integument finely punctured and covered with dense and extremely thin setae.
Elytra subconical in dorsal view, external margins feebly but distinctly curving from the elytral humeri towards the apices; elytra apices rounded, not converging at the suture. Elytra strongly and densely punctate; each puncture bears a spiniform seta, especially on the elytral disc.
Metepisterna of the Mordellistena-type (sensu
Abdomen. Abdomen conical, tapered in both lateral and dorsal view; abdominal ventrite 1 longer than ventrites 2 to 4, and 1.25× as long as hypopygidium. Pygidium conical in dorsal view, 2.5× longer than wide at the base; in lateral view the pygidium is conical, slightly bending downward towards the base, 2.4× as long as hypopygidium. Sternite 8 strongly produced in the middle of the posterior edge, 1.7× longer than wide at the base, posterior margin bearing long setae (Fig.
Paramera asymmetric, of the Mordella-type (sensu
The species was originally described as Mordella based on a single male specimen, but its diagnosis was based exclusively on its external features, color pattern especially (
In the same year, Franciscolo renamed the taxon Mordella cuomoi (
It is important to point out that the species, since its description, has not been found again despite major sampling efforts (E. Ruzzier pers. comm.), and its real identity has remained somewhat uncertain until now.
The possibility of studying the holotype finally allowed us to produce these considerations: 1) the species has to be treated in its original combination since it does not possess those morphological features typical of Variimorda, namely antennal dilatation starting from antennomere 5 (antennal dilatation starting from antennomere 4 in Variimorda) and left paramere of the Mordella-type, short and claviform (knobbed on the inner margin and provided with a well-developed distal membranous process in Variimorda); 2) the species does not belong to the Italian fauna, and the locality is most likely the result of a labeling error. This interpretation is supported by the fact that the original specimen label gives February as the month of collection; winter in Italy does not present the climatic conditions to allow the survival of the adults nor favor the presence of flowering plants that could support its survival. In addition, the fact that the species has not been found again in the locus typicus, nor in the biogeographically associated and contiguous areas, further supports the idea that the species is not an element of the Italian fauna. Furthermore, its morphological features and general aspect do not resemble any Western Palaearctic member of the tribe Mordellini, with the only exception of a vague affinity with Mordellaria aurofasciata (Comolli, 1837). It is currently impossible to determine a plausible origin of this taxon.
Mordellistena (Mordellokoiles) grandii
Franciscolo, 1942: 134;
Mordellokoiles grandii:
Mordellistena (Mordellokoides)
[sic!] grandii:
Holotype
(female, not male as stated in the original description) and two paratypes (both females) labeled “Calabria, V. del Crati, Leoni” (
Conservation state: the holotype and one paratype are moderately damaged, missing antennomeres, tarsi, and some legs (including posteriors).
Measurements. Holotype. HL: 1.2 mm; HW: 1.4 mm; PL: 1.5 mm; PW 1.9 mm; EL: 4.6 mm; EW: 1.9 mm; PygL 1.1 mm; HpygL 0.5 mm; TL: 8.4 mm.
Color. Integument reddish brown to brown; head and ventrites darker (Fig.
Head. Head moderately transverse in dorsal view (1.2× wider than long), sub-hemispheric but slightly flattened in lateral view (Fig.
Antennae filiform (missing in the holotype and one paratype); antennomeres 1–4 cylindrical, with 1 and 2 slightly longer and thicker than 3 and 4; antennomeres 5–10 expanded and only slightly serrated, elongated, 1.7–1.9× longer than wide; apical antennomere asymmetrically ellipsoid, slightly impressed on its inner apical side, 1.9× longer than wide (visible only in one paratype).
Prothorax. Pronotum trapezoidal in dorsal view, 1.3× wider than long, widest on its basal third, slightly convex in lateral view, the convexity increases towards the posterior third of the pronotum; pronotal disc smooth but densely covered with impressed setigerous punctures bearing recumbent and posteriorly oriented setae, punctures larger than those on head. Anterior margin not visible from above since the anterior angles curve downward; in dorsal view, lateral margins of the pronotum roundly and gently converge to the neck. Posterior margin of the pronotum irregular, with the central lobe protruding posteriad. Anterior and posterior angles of the pronotum obtuse in lateral view; lateral margins of pronotum straight in lateral view.
Pterothorax. Scutellum triangular, finely punctured, and covered with dense, thin setae.
Elytra 2.4× longer than wide, parallel in dorsal view (Fig.
Hind wing (paratype) of the Mordellistena-type (see
Metepisterna of the Mordellistena-type (sensu
Mesofemora laterally compressed; mesotibia cylindrical and only feebly curved in dorso-lateral view; mesotarsus 1.1× as long as mesotibia. Metafemora straight, laterally compressed; metatibiae conical, transversely truncate at apex; subapical comb present, short and not running parallel to the apical margin of the tibia; dorso-lateral side of metatibia bearing two strongly oblique combs with the proximal longer than the distal. Metatarsomere 1 bearing three oblique, parallel combs, metatarsomere 2 with two, metatarsomere 3 with one comb, and metatarsomere 4 devoid of any. Metatibial spurs asymmetrical with the inner 2.6× as long as the outer.
Abdomen. Abdomen conical, tapered in both lateral and dorsal view; abdominal ventrite 1 almost of the same length as ventrite 2 and 3, ventrite 4 is the shortest. Pygidium conical in dorsal view, 1.8× longer than wide at the base; in lateral view the pygidium is conical, slightly bending downward towards the base, 2.2× as long as hypopygidium.
Mordellokoiles grandii represents another case of a species described as native to Italy by Franciscolo but never found again since its description. Examination of the type material suggests that this taxon does not belong to the Western Palaearctic fauna and especially poses serious difficulties in framing Mordellokoiles with respect to the other genera of Mordellistenini.
As with Mordella quomoi, the description of the new taxon is rather synthetic, not accompanied by adequate iconography, the sex of the holotype is clearly mistaken (male instead of female), and the establishment of the subgenus Mordellokoiles is based on a sole antennal character of rather dubious validity (shape of the last antennomere). Because M. grandii possesses the penultimate tarsomere of the anterior and middle tarsi dilated, it cannot be considered in any way as a subgenus of Mordellistena Costa, 1854, a genus that possesses cylindrical and apically truncated pro- and mesotarsomeres. Furthermore, this taxon cannot be assigned to any of the Western Palaearctic Mordellistenini with a similar tarsal character, such as Tolida Mulsant, 1856, Dellamora Normand, 1916, or Pseudodellamora Ermisch, 1942, because it differs from these in its general aspect and other characters. However, Mordellokoiles is rather similar to some Oriental and Eastern Palaearctic genera, such as Falsomordellistena Ermisch, 1941, Glipostenoda Ermisch, 1950 or Pulchrimorda Ermisch, 1968. However, it cannot be treated as a synonym of any of these because characters required to identify and separate the genera are almost exclusively sexually dimorphic, and it is the male that usually possess the most informative traits. Consequently, any placements of Mordellokoiles in any of the already existing genera could be incorrect, as this taxon establishment was based exclusively on females; therefore, we consider it appropriate to elevate Mordellokoiles to a genus rank, pending future reassignment if the male is discovered.
The results presented here demonstrate once again how the examination and redescription of type material is a key step in clarifying the identity and distribution of the Western Palaearctic Mordellidae. The assignment of Mediimorda argyropleura, Mordella quomoi, and Mordellokoiles grandii to the Italian fauna by Franciscolo derives most probably from labeling mistakes possibly due to poor management of specimens collected or studied in the early years of his entomological career, as already noted by
The authors would like to thank Roberto Poggi (Museo Civico di Storia Naturale “G. Doria” – Genoa, Italy) for granting the study of the material in his care; and Alberto Ballerio (Brescia), Larry Bezark (California Department of Food and Agriculture), Robert Naczi (New York Botanical Garden), and the anonymous reviewers for providing valuable comments that improved the quality of this manuscript.
The authors have declared that no competing interests exist.
No ethical statement was reported.
The authors acknowledge the support of NBFC to the University of Roma Tre, Department of Science, funded by the Italian Ministry of University and Research, PNRR, Missione 4 Componente 2, ‘Dalla ricerca all’impresa’, Investimento 1.4, Project CN00000033.
Both authors have contributed equally.
Enrico Ruzzier https://orcid.org/0000-0003-1020-1247
Andrea Di Giulio https://orcid.org/0000-0003-0508-0751
All of the data that support the findings of this study are available in the main text.