Taphioporus rufous, Bukejs, Andris & Moseyko, Alexey G., 2015

Bukejs, Andris & Moseyko, Alexey G., 2015, Two new species of the genus Taphioporus Moseyko & Kirejtshuk (Chrysomelidae: Eumolpinae) from Baltic amber, Zootaxa 4032 (4), pp. 395-406 : 396-402

Taphioporus rufous sp. nov.

( Figs 1–6 )

Type. Holotype: Nr. “C 8002”, “ Holotype / Taphioporus rufous sp. nov. / des. Bukejs A. & Moseyko A.G.” [red printed label]; sex unknown. The rather complete beetle missing left meso- and metatarsi is included in a small, transparent, polished subquadratic amber piece (length about 31 mm, width 27 mm, and maximum thickness 9 mm), that is yellowish in color, and prepared without supplementary fixation. Mouthparts and left side of specimen are partly obscured by a “milky” opacity. There are also one Oribatida (Acari), one stellate fagacean trichome, and a few small gas vesicles trapped within the examined amber piece.

Type strata. Baltic amber, Late Eocene, Prussian Formation (Priabonian). Estimated age: 37.2–33.9 Ma.

Type locality. Yantarny settlement [formerly Palmnicken], on the Sambian [Samland] peninsula, in the Kaliningrad region, Russia.

Etymology. Specific epithet is from the Latin “ rufous ” and refers to the reddish-brown body coloration of the new species.

Differential diagnosis. Taphioporus rufous sp. nov. differs from T. balticus in having larger and denser pronotal punctation, head with fine punctures, and paler coloration of body. T. rufous sp. nov. differs from T. carsteni sp. nov. in shape of convex part of “propleura”, almost straight lateral margins of pronotum in posterior half, finer and sparser punctation of abdomen, and pale brown body.

Description. Body length 3.25 mm; body shape elongate oval in dorsal outline, moderately convex dorsally and ventrally; pale brown with head, pronotum, and elytral punctures rufous , and trochanters reddish brown; glabrous (except abdomen and legs).

Head hypognathous, frons and vertex with fine and sparse punctures. Compound eyes medium-sized, moderately convex, slightly emarginate at antennal insertions. Paraocular grooves present. Antennae filiform, long, extending nearly to middle of elytra; antennomeres 1–3 not visible because of “milky” opacity; antennomeres 4–6 subcylindrical, subequal in size, about 2.8 times as long as wide; antennomere 7 distinctly dilated apically, 2.5 times as long as wide, and about 1.1 times as long as antennomere 8; antennomeres 8–10 dilated apically, equal in shape and size, each about 2.3 times as long as wide; antennomere 11 elongated oval with pointed apex, about 1.1 times as long as antennomere 10.

Pronotum transverse; with small (nearly as large as diameter of one compound eye facet) and dense punctures, distance between punctures equal to 1–3 times diameter of one puncture, punctation distinctly sparser posteriorly. Posterior margin sinuate, with distinct bordering carina; lateral margins almost straight (in lateral view), with narrow bordering carinae; anterior margin arcuate, with narrow bordering carina. Posterior angles widely rounded; anterior angles nearly rectangular. Anterolateral sides of prosternum (“propleura”) convex with anterior margin straight medially; prosternum with well-pronounced antennal grooves; covered with fine, sparse punctures. Prohypomera with few fine punctures, shiny. Procoxae nearly round, shagreened; procoxal cavities closed posteriorly.

Scutellum moderately large, subtriangular with widely rounded apex, flat, impunctate. Elytra 2.4 times as long as pronotum, with bases wider than pronotal posterior margin; humeral calli well-developed, distinctly projecting. Elytral punctures round, small (slightly larger than pronotal punctures), dense, arranged in regular striae; distance between strial punctures equal to 1–2 times diameter of one puncture. Each elytron with 12 striae, stria 1 shortened (extending only within basal one-quarter of elytral length), striae 1–6 and 12 reaching base of elytra, striae 11 and 12 fused in middle, striae distinct throughout entire length of elytron; distance between striae approximately 2–3 times diameter of single puncture; intervals flat (slightly convex in apical one-fifth of length), and smooth. Pygidium not exposed.

Epipleura without punctures, widest in basal half, gradually narrowing posteriorly, reaching elytral apex. Metepisternum about 4 times as long as wide, slightly dilated anteriad; with row of fine punctures near exterior lateral margin (distinctly visible in posterior half); anterior margin oblique, lateral margins slightly emarginate. Metaventrite slightly convex, almost smooth (only with row of small punctures at lateral and anterior margins). Metepisternum and metaventrite with well developed border along lateral margins. Coxae with strong microreticulation; mesocoxae oval; metacoxae elongated oval, with transverse carina medially, distance between meso- and metacoxae nearly equal to 0.7 times transverse diameter of metacoxa.

Abdomen with five ventrites, slightly convex; covered with very fine and sparse indistinct punctures, and with fine, recumbent pale setae. Ventrite 1 the longest, twice as long as ventrite 2; abdominal intercoxal process rectangular, with rounded anterior angles. Ventrites 2–4 subequal in length. Relative length ratios of ventrites 1–5 (medially): 14-7-5-5-7. Ventrite 5 with widely rounded posterior margin and with shallow emargination apically.

Legs relatively long and slender, with fine, indistinct pubescence. Femora spindle-shaped, distinctly widened near mid-length; without teeth ventrally. Tibiae without preapical emargination, slightly widened apically, with setae at apices. Tarsomere 2 slightly bilobed, tarsomere 3 deeply bilobed. Metafemora 3.4 times as long as wide; metatibiae 5.1 times as long as wide. Metafemur 1.4 times as long as metatibia; metatarsus 0.7 times as long as metatibia. Relative length ratios of metatarsomeres 1–4: 11-9-7-12. Claws appendiculate, long.

Taphioporus carsteni sp. nov. ( Figs 7–17 )

Types. Holotype: Nr. “C 923”, “ Holotype / Taphioporus carsteni sp. nov. / des. Bukejs A. & Moseyko A.G.” [red printed label]; sex unknown. The complete beetle with partly exposed hind wings is included in a small, rather transparent, polished subquadratic amber piece (length 21 mm, width 18 mm, and maximum thickness 7 mm), that is yellowish–orange in color, and preserved without supplementary fixation. There are also a few stellate fagacean trichomes, and small gas vesicles in the examined amber piece.

Paratype: Nr. “C 1183” “ Paratype / Taphioporus carsteni sp. nov. / des. Bukejs A. & Moseyko A.G.” [red printed label]; sex unknown. The complete beetle is included in a small, rather transparent, polished subrectangular amber piece (length 18 mm, width 12 mm, and maximum thickness 5 mm), with yellowish color, and without supplementary fixation. Ventral part of thorax and head are partly obscured by a “milky” opacity. There are also four stellate fagacean trichomes, a few small gas vesicles, and a few small pieces of organic material in the examined amber piece.

Type strata. Baltic amber, Late Eocene, Prussian Formation (Priabonian). Estimated age: 37.2–33.9 Ma.

Type locality. Yantarny settlement [formerly Palmnicken], of the Sambian [Samland] peninsula, within the Kaliningrad region, Russia.

Etymology. Patronymic, this new species is named after Carsten Gröhn (Glinde, Germany), who enabled us to study these specimens.

Differential diagnosis. Taphioporus carsteni sp. nov. differs from T. balticus in having larger and denser pronotal punctation, and head with fine punctures; compared to T. rufous sp. nov., it differs in shape of convex part of “propleura”, and in having slightly rounded lateral margins of pronotum, larger and denser punctation of abdomen, and black body coloration.

Description. Holotype. Body length 3.3 mm, maximal width 1.6 mm, body shape forming elongate oval in dorsal view, moderately convex dorsally and ventrally; black in color, with palpomeres, antennae, tarsomere 4, and claws reddish–brown; glabrous (except abdomen and legs).

Head hypognathous, with fine and sparse punctures. Compound eyes medium-sized, moderately convex, slightly emarginate at antennal insertions. Paraocular grooves present. Clypeus with slightly emarginated anterior margin; clypeo-frontal suture absent. Antennae filiform, long; antennomere 11 elongated oval in outline, with pointed apex; antennae not clearly visible because of amber structure and specimen location within amber piece.

Pronotum transverse, about 1.5 times as wide as long, widest posteriorly, gradually narrowing anteriad; with small (nearly as large as diameter of one compound eye facet) and dense punctures; distance between punctures equal to 1–3 times diameter of one puncture; punctation distinctly sparser at base. Posterior margin sinuate, with distinct carinate border; lateral margins slightly rounded (in lateral view), with narrow carinate border; anterior margin arcuate, with narrow carina along border. Posterior and anterior angles widely rounded. Anterolateral sides of prosternum convex, with anterior margin slightly rounded, with well-pronounced antennal grooves, with few fine punctures, and strongly shagreened. Prohypomera with few fine punctures, shiny. Proventrite strongly shagreened. Procoxae nearly round, shagreened; procoxal cavities closed posteriorly.

Scutellum moderately large, transverse, about 1.3 times as wide as long, subtriangular with widely rounded apex, flat, impunctate. Elytra widely oval in outline, widest within apical one-third of length, with subparallel lateral sides, 1.5 times as long as wide, about 2.8 times as long as pronotum, with anterior margin distinctly wider than pronotum; humeral calli well-developed, distinctly projecting. Elytral punctures round, small (yet distinctly larger than pronotal punctures), dense, arranged in regular striae; distance between strial punctures equal to 1–2 times diameter of one puncture. Each elytron with 12 striae, stria 1 shortened (extending only in basal one-quarter of elytron), striae 1–6 and 12 reaching base of elytron, striae 11 and 12 fused in middle, but most striae are distinct throughout entire length of elytron; distance between striae approximately 2–3 times diameter of puncture; intervals slightly convex, smooth, shiny. Pygidium not exposed. Hind wings present.

Epipleura without punctures, widest in basal half, gradually narrowing posteriorly, and reaching elytral apex. Mesoventrite with strong, transverse microsculpture. Metepisterna about 5 times as long as wide, slightly dilated anteriad; with row of fine punctures at exterior lateral margin (distinctly visible in posterior half); anterior margin oblique, lateral margins slightly emarginate. Metaventrite convex, almost impunctured (only with row of fine punctures at lateral and anterior margins), weakly shagreened. Metepisternum and metaventrite with well developed border along lateral margins. Coxae with strong microreticulation; mesocoxae oval; metacoxae elongated oval with transverse carina medially; distance between meso- and metacoxae nearly equal to 0.6 times transverse diameter of metacoxa.

Abdomen with five ventrites, slightly convex; covered with small and dense punctures (nearly as large as pronotal punctures), and with fine, recumbent pale setae. Ventrite 1 the longest, about 2.4 times as long as ventrite 2; abdominal intercoxal process transverse, rectangular, with rounded anterior angles. Ventrites 2–4 subequal in length.

Legs relatively long and slender. Femora spindle-shaped, distinctly widened near mid-length; without teeth ventrally. Tibiae without preapical emargination, slightly widened apically, at apices with setae. Tarsomere 2 slightly bilobed, and 3 deeply bilobed. Metafemora 3.5 times as long as wide; metatibiae about 8 times as long as wide. Metatibiae nearly as long as metafemora; metatarsus about 0.7 times as long as metatibia. Relative length ratios of metatarsomeres 1–4: 9-6-5-8. Claws appendiculate, long.

Paratype. Body length 3.3 mm, unicolorous black. Antennae filiform, long, extending nearly to middle of elytra; scape cylindrical, short; pedicel subequal in length and nearly 1.7 times as wide as antennomere 3; antennomeres 3–6 subcylindrical, slender; antennomere 7 distinctly dilated apically, about 2.8 times as long as wide, and nearly as long as antennomere 6; antennomeres 9–10 robust, dilated apically, subequal in shape and size, antennomere 9 about 2.2 times as long as wide; antennomere 11 elongated oval with pointed apex, about 2.4 times as long as wide, and 1.1 times as long as antennomere 10. Pubescence of abdomen more conspicuous than in holotype. Ventrite 5 with shallow, indistinct apical emargination. Relative length ratios of ventrites 1–5 (medially): 11-4-3-3-6.

Figures

FIGURES 1 – 2. Taphioporus rufous sp. nov., Holotype, C 8002: 1 — habitus, lateral view; 2 — habitus, ventro-lateral view.

FIGURES 3 – 6. Taphioporus rufous sp. nov., Holotype, C 8002: 3 — details of forebody, lateral view; 4 — abdomen; 5 — right mesotibia and tarsus; 6 — apical part of left antenna.

FIGURES 7 – 8. Taphioporus carsteni sp. nov., Holotype, C 923: 7 — habitus, dorsal view; 8 — habitus, lateral view.

FIGURES 9 – 11. Taphioporus carsteni sp. nov., Holotype, C 923: 9 — habitus, ventral view; 10 — pronotum, dorsal view; 11 — head, frontal view.

FIGURES 12 – 13. Taphioporus carsteni sp. nov., Paratype, C 1183: 12 — habitus, dorsal view; 13 — habitus, ventral view.

FIGURES 14 – 17. Taphioporus carsteni sp. nov., Paratype, C 1183: 14 — right antenna; 15 — abdomen; 16 — head and pronotum, dorso-frontal view; 17 — left protibia and protarsus.