Mordella quomoi Franciscolo, 1942

Ruzzier, Enrico & Di Giulio, Andrea, 2024, Taxonomic considerations of selected Western Palaearctic Mordellidae Latreille, 1802 (Coleoptera, Tenebrionoidea), ZooKeys 1207, pp. 151-165 : 151-165

Mordella quomoi Franciscolo, 1942 comb. rev.

Mordella quomoi Franciscolo, 1942 a: 7 .

Mordella cuomoi Franciscolo, 1942 b: 22 (subsequent unjustified emendation).

Variimorda (Variimorda) quomoi : Horák 1985: 11; Ruzzier 2013: 106; Horák 2020: 87.

Variimorda (Variimorda) quomoi (Franciscolo, 1951 [sic!]): Franciscolo 1995: 11.

Material.

Holotype (by monotypy), male, labeled “ Is. Giglio , II. 1902. G. Doria // Typus // Mordella Quomoi Franciscolo (handwritten) // Mordella quomoi Francisc. det. M. E. Franciscolo ” ( MSNG) ( Fig. 3 A ).

Conservation state: modest, antennae and anterior tarsomeres broken, partially missing.

Redescription.

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. 3 B, C ). Head uniformly covered with golden recumbent setation. Pronotum on disc covered with recumbent, posteriorly oriented, dark-brown setae; margins and the posterior lobe of the pronotum covered with golden setation as on the head. Scutellum bearing pale-yellowish setae. Elytron covered with dark-brown, recumbent setae as on pronotum, except for a band of yellowish setae, which, starting from the scutellum and following the anterior margin of the elytron, delimits the elytral callus and converges toward the elytral suture, forming a semicircular pattern; in addition, the elytron presents a sub-squared patch of yellowish setae at about three-quarters of its length, close to the elytral suture. Meso and metathoracic ventrites, as well as the basal part of all abdominal ventrites, covered with recumbent, yellowish setae.

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 (3 B); occipital margin almost straight in dorsal view ( Fig. 3 D ); integument nearly smooth but densely covered with setigerous punctures. Eyes large, setose, and finely facetted, almost circular in lateral view, extending anteriorly to the antennal insertion and posteriorly to the occiput. Anterior margin of the epistoma straight; exposed part of exposed part of labrum transverse, gently curved at the anterior margin, setose. Maxillary palpus of the Mordella - type (sensu Franciscolo 1957) ( Fig. 4 A ); first maxillary palpomere flattened, club-shaped, and about 4 × its maximum width; second maxillary palpomere short, subconical, 1.7 × as long as its maximum width; apical (third) maxillary palpomere securiform, scalene triangular, 2.1 × as long as its maximum width, outer margin of the segment (the longest) feebly sinuate. Antennomeres 1–4 subcylindrical, short; antennomeres 1 and 2 stouter than the following two. Antennomeres 6–10 1.9–2.0 × longer than wide (the fifth is missing); apical antennomere asymmetrically ellipsoid, 2.6 × as long as wide ( Fig. 3 B ).

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 Franciscolo 1957), triangular, 2.1 × as long as their maximum width; sutures between Metepisterna and metaventrite marked and straight. Coxae (coxal plates) semicircular, 2.1 × as wide as their maximum length. Metepisterna, metaventrite, and coxae on their dorsal two-thirds densely covered with setigerous punctures like those on pronotum and elytra. Mesofemora laterally compressed; mesotibia cylindrical and feebly curved; mesotibia as long as the mesotarsus. Metafemora straight, laterally compressed; metatibiae conical, transversely truncate at apex; subapical comb present, short and running parallel to the apical margin of the tibia; dorsal side of metatibia bearing a series of sparsely arranged spines that vaguely resemble a longitudinal comb; metatarsomeres devoid of combs or arranged spinulations. Metatibial spurs slightly asymmetrical with the inner 1.1 × as long as the outer.

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. 3 C ).

Paramera asymmetric, of the Mordella - type (sensu Franciscolo 1957) ( Fig. 4 D ). Right paramere U-shaped, dorsal process longer than the ventral, straight, lanceolate and only weakly sclerotized; ventral process short, strongly sclerotized and pointed at apex, presenting a dentiform process on its internal margin. Left paramere stout, claviform, strongly sclerotized, presenting a pointed straight process at the distal apex.

Comments.

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 ( Franciscolo 1942 a). Franciscolo named this new taxon after his high-school teacher Maria Enrichetta Cuomo Ulloa ( Franciscolo 1942 a, 1942 b).

In the same year, Franciscolo renamed the taxon Mordella cuomoi ( Franciscolo 1942 b) , whose nomenclatural act constitutes in all respects a subsequent unjustified emendation in accordance with Article 33 of the International Code of Zoological Nomenclature ( ICZN 1999). The species was then transferred to Variimorda Méquignon, 1946 as Variimorda (Variimorda) quomoi by Horák (1985), without taking into account the nomenclature act (despite being incorrect) proposed by Franciscolo 1942; the fact that Horák referred to the holotype as female, when it is clearly male, suggests that the transfer to Variimorda was made solely on the basis of the chromatic pattern. Particularly unusual is the assignment by Franciscolo of M. quomoi to Variimorda in his checklist of the Italian fauna ( Franciscolo 1995); the move to another genus is completely unjustified, given the total lack of footnotes or references in the publication, and completely ignoring the taxonomic change proposed by the same author as many as 50 years earlier. Franciscolo then, without referring to the taxonomic change that had already occurred in Horák (1985), proposed “ his ” combination V. (V.) quomoi , but mistaking its year of description (1951 instead of 1942). The combination Variimorda (Variimorda) quomoi (Franciscolo, 1942) (sensu Horák 1985) was then maintained in the few subsequent references mentioning the taxon ( Horák 2008; Ruzzier 2013; Horák 2020). Since the species was originally named after a woman, the correct spelling of the specific epithet should have been “ quomoae ” (feminine) instead of “ quomoi ” (masculine); however, we opt to retain the masculine form to maintain consistency with previous literature.

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.

Figures

Figure 3. Mordella quomoi Franciscolo, 1942, holotype A original labels B dorsal habitus C lateral left view D detail of head and pronotum in dorsal view. Scale bar: 2.0 mm.

Figure 4. Mordella quomoi Franciscolo, 1942, holotype A right maxillary palpus B left antennomeres 6–10 C 8 th sternite D paramera, (R) right and (L) left.