Tomosomus pallidicornis ( Champion, 1890 ) Telnov & Gusakov, 2023

Telnov, Dmitry & Gusakov, Alexey A., 2023, Rediscovery of Tomosomus Motschulsky, 1855 (Coleoptera: Anthicidae) with redescription of the genus, a new genus-rank synonym, and a key to species, Zootaxa 5293 (3), pp. 541-556 : 548-554

Tomosomus pallidicornis ( Champion, 1890) comb. nov. ( Figs 5–7 )

= Tomoderus scydmaenideus Pic, 1894

Holcopyge pallidicornis — Champion (1890: 292) original description; Pic (1911: 26) checklist; Lucas (1920: 330) checklist; Blackwelder (1945: 432) checklist.

Tomoderus scydmaenideus — Pic (1894b: 59) original description, as scydmaenideus ; Pic (1894c: 137–138) correction, synonymy, checklist; Pic (1897: 213), as scydmaenideus , repeated note on synonymy.

Tomoderus sydmaenideus — Pic (1894a: 46) checklist, misspelling of scydmaenideus .

Type material examined. Lectotype [designated herewith] ♁ BMNH ( Figs 5 , 7 ): 704 [printed, label reddish] // New Grenada [handwritten, label circular] // Holcopyge pallidicornis , ♁ Ch. [handwritten] // F. Bates 81. 19 [printed].

Paralectotypes 2 specimens. 1♁ BMNH ( Fig. 6 ): Bogotá Colombia Petersen [handwritten] // Holcopyge pallidicornis , ♁ Ch. [handwritten] // G.C.Champion Coll. B.M. 1927–409. [printed] // Holcopyge pallidicornis Champ. vid. D.Telnov, 2019 [printed]. The second paralectotype is on loan and was not available for the present study.

Nomenclature. Champion (1890: 293) mentions three specimens (which all become syntypes) in the original description but states the description was made from two males. The lectotype designation is made in order to maintain nomenclatural stability.

Taxonomy. The name Tomoderus scydmaenideus first appears in the addition to the checklist of Anthicidae ( Pic 1894a: 46, as ‘ sydmaenideus ’ [sic!]) referring to the original description published in a separate paper in the same issue of the same journal ( Pic 1894b: 59). According to the ICZN (1999), page priority is abolished and names in the same journal published same date are synchronous. Therefore, the name Tomoderus scydmaenideus , which was described several pages beyond ( Pic 1894b) it first mentioned in the checklist ( Pic 1894a) under the misspelt name ‘ sydmaenideus ’ is available and valid. The name ‘ Tomoderus sydmaenideus ’ in Pic (1894a) is a clear misspelling of Tomoderus scydmaenideus as later pointed out in Pic (1894c).

Redescription. ♁ lectotype, total body length 2.7 mm; head 0.5 mm long, across compound eyes 0.6 mm broad, pronotum 0.6 mm long, maximum width 0.55 mm, minimum width 0.3 mm, elytra 1.6 mm long, 1.2 mm combined wide.

Dorsum and venter uniformly pale brown, base of pronotum very narrowly blackish. Mouthparts, antennae, palps and legs pale yellow, abdomen yellowish brown. Head strongly ovoid, glossy dorsally and ventrally, slightly convex in dorsal aspect. Anterolateral margin of frons slightly bulging between antennal insertion and internal anterior margin of a compound eye. Compound eye moderate, slightly protruding beyond lateral outline of head. Tempora rounded in one broad arc with head base; posterior temporal angled fully rounded. Head base subtruncate medially. Head dorsal punctures moderately large, sparse. Head dorsal setae yellowish, rather long. Antenna slender, extending slightly beyond humeral area of elytron when directed posteriad. Antennomere three slightly longer than antennomere two, antennomeres 8–10 somewhat thickened, penultimate antennomere transverse. Terminal antennomere elongate triangular with tapered apex, asymmetrical, 2.3× as long as penultimate antennomere. Penultimate maxillary palpomere subtriangular. Terminal maxillary palpomere securiform. Pronotum dorsally and laterally glossy, slightly convex in dorsal aspect, anterior lobe somewhat narrower than head across compound eyes. Front margin of anterior lobe very broadly rounded to subtruncate, dorsally and laterally with very narrow anterior rim. Posterior lobe strongly narrower and shorter than anterior. Postmedian lateral constriction deep and broad, dorsally with a row of irregular, short wrinkles separated by raised, narrow, longitudinally directed intervening spaces, continues onto pronotal disc as a distinct depression (in lateral view). Pronotal punctures minute and sparse. Dorsal pronotal setae yellowish, sparse, subdecumbent. Pronotal tactile setae long, erect, sporadic, aligned along with lateral margins of anterior lobe of pronotum. Scutellar shield minute, subtriangular, rounded at posterior margin. Elytra ovoid, moderately convex in dorsal aspect, widened laterally before midlength, humerus obsolete (apterous species). Elytral punctures stronger and larger than those on dorsal forebody, arranged into confused rows, becoming significantly smaller and flat on posterior half of elytron. Intervening spaces glossy and glabrous, significantly wider than punctures. Epipleuron nearly complete, particularly broad in basal half. Elytral setae yellowish, long and rather dense, suberect to erect. Profemur clavate, meso- and metafemur indistinctly clavate. Basal metatarsomere slightly longer than combined length of remaining metatarsomeres. Tergite VII broadly rounded at posterior margin, with broad median longitudinal furrow ( Fig. 7A– B ). Morphological sternite VII subtruncate at posterior margin ( Fig. 7C ). Morphological sternite VIII deeply П-like emarginate at posterior margin ( Fig. 7D ). Morphological sternite IX as in Fig. 7E . Aedeagus elongate, subtubular, apically hook-like shaped in lateral view ( Fig. 7F ).

Sexual dimorphism. Unknown.

Ecology. Unknown.

Distribution. Colombia (Andean Mountains region?).

Type depository. BMNH.

Figures

FIGURE 5. Tomosomus pallidicornis (Champion, 1890), lectotype ♁. A—Habitus, dorsal view; B—ditto, lateral view.

FIGURE 6. Tomosomus pallidicornis (Champion, 1890), paralectotype ♁, habitus, dorsal view.

FIGURE 7. Tomosomus pallidicornis (Champion, 1890), lectotype ♁, terminalia and genitalia.A—Tergite VII, dorsal view; B— Part of a median furrow of tergite VII, dorsal view (enlarged); C—Morphological sternite VII, ventral view; D—Morphological sternite VIII, ventral view; E—Morphological sternite IX; F—Aedeagus, lateral view [not to scale].