Statira baltica, Telnov & Bukejs & Merkl, 2019

Telnov, Dmitry, Bukejs, Andris & Merkl, Ottó, 2019, Description of a new fossil Statira Lepeletier et Audinet-Serville, 1828 (Coleoptera Tenebrionidae: Lagriinae) from Baltic amber of the Sambian Peninsula, Zootaxa 4683 (4), pp. 508-514 : 509-512

Statira baltica sp. nov.

( Figs 1–6 )

http://zoobank.org/ 95EDBFFF-FD47-4B49-9B41-AA8E59540127

Etymology. Toponymic. Named after the Baltic Sea and region.

Material. Holotype, adult ♂ “ MAIG 5982 , ex. coll. Jonas Damzen JD 4694” [ MAIG]: complete beetle inclu- sion with partially exposed aedeagus, included in transparent yellow piece of amber with dimensions 55×33× 13 mm; ventral side of specimen and mouthparts almost completely obscured by “milky” opacity. Syninclusions: one very small (0.25 mm) specimen of an unidentified Arachnida, few stellate Fagaceae trichomes, few small pieces of organic material, and many small gas vesicles.

Type strata. Baltic amber, mid Eocene to Upper Eocene, Prussian Formation .

Type locality. Baltic Sea coast, Yantarny settlement (formerly Palmnicken), Kaliningrad Region, Russia .

Description. Total body length about 10.6 mm; body elongate, slender, moderately convex dorsally; dorsum brown with head, antennae, small humeral spot on each elytron, meso- and metasternum, meso- and metatibiae, all tarsi, and abdomen darker brown to black.

Head prognathous, transverse, with constriction posteriorly forming broad neck, finely and densely punctate dorsally, with few scattered long erect setae. Genae prominent, apparently impunctate. Frons with vague median impression. Eyes large, reniform with medially shallowly emarginate inner margin, slightly prominent, interocular distance about 2.3× eye diameter. Tempora about as long as eye length in dorsal view, obliquely tapering towards neck. Terminal maxillary palpomere securiform. Antennae of 11 antennomeres, filiform, long, reaching midlength of abdominal ventrite 1, with sparse erect to semierect setae; scape subcylindrical with oblique posterior margin, 0.7× as wide as pedicel; pedicel short, about 0.5× as long as antennomere 3; intermediary antennomeres elongate, slightly dilated apically; terminal antennomere slightly curved, strongly elongate, distinctly longer than combined length of antennomeres 7–10, without crenulation at inner margin; relative length ratios of antennomeres 1– 11 equal to 9-5- 11-11-13-13 - 13-12-11-9 -54.

Prothorax. Pronotum slightly longer than wide, widest in anterior one-third, constricted before base, slightly narrowed anteriad; disc finely and densely punctate, intervening spaces smaller than punctures; disc with dense, short recumbent to semierect setae. Lateral margins with a weak bead, broadly rounded in anterior half; anterior margin slightly concave mesally; posterior margin nearly straight, upturned. Anterior corners widely rounded, posterior corners distinct, orthogonal. Pronotal disc flattened, with shallow medio-lateral impressions. Prothoracic hypomera delicately punctured; prosternum in front of procoxal cavities much longer than double diameter of a procoxal cavity; prosternal process narrow, slightly convex. Scutellum small, rounded apically.

Pterothorax. Elytra moderately convex, elongate-oval, parallel-sided, slightly widened posteriorly, widest in posterior fifth, about 2.2× as long as wide combined, 4.7× as long as pronotum; humeral callosity prominent; disc moderately densely covered with fine pale recumbent pubescence, and scattered very long erect setae. Elytral punctation delicate and dense, arranged in indistinct rows; intervals between rows slightly convex and with fine additional punctures. Epipleura narrow. Metepisternum wide, with almost straight lateral margins, apparently without distinct punctation.

Legs long and slender, covered with fine recumbent pubescence; procoxal cavities presumably closed (not visible due to position of specimen); procoxae globose; mesocoxae subglobose; all coxae not contiguous; femora distinctly longer than tibiae, not clavate, slightly flattened; all tibiae slightly dilated apically, each with one short apical spur; protibiae straight, meso- and metatibiae slightly curved; femora and tibiae without modifications; tarsi long, nearly as long as tibiae, penultimate tarsomere bilobed; relative length ratios of mesotarsomeres 1–5 equal to 11-6-5-3 -71; relative length ratios of metatarsomeres 1–4 equal to 20-9-5-9; claws narrow, free and simple.

Abdomen with five visible ventrites, sparsely covered with short, erect setae. Aedeagus with basale not visible; apicale narrowly triangular, tapered apically in ventral view, straight in lateral view.

Differential diagnosis. Statira baltica sp. nov. readily differs from S. dermoidea Doyen et Poinar, 1994 (Dominican amber) in the combination of following morphological features: pronotal disc with shallow medio-lateral impressions (pronotal disc with about six irregular, flattened longitudinal carinae in S. dermoidea ); inner margin of terminal antennomere without crenulation (gently crenulate in S. dermoidea ); and larger body; each elytron with small black humeral spot (elytra with black postmedian spot in S. dermoidea ).

Figures

FIGURES 1–2. Statira baltica sp. nov, holotype ♂: 1—habitus, dorso-lateral view; 2—habitus, ventro-lateral view.All photos: Jonas Damzen (Vilnius, Lithuania). Scale bars represent 2 mm.

FIGURES 3–6. Statira baltica sp. nov, holotype ♂: 3—details of forebody and antena, lateral view; 4—apical portion of elytra, dorso-lateral view; 5—right metatarsus; 6—apical portion of aedeagus, lateral view.All photos: Jonas Damzen (Vilnius, Lithua- nia). Not reproduced to the same scale.