Rhomeocalpsua torosa Li, Tomaszewska & Cai 2022, sp. nov.
Creators: name: Li, Yan-da
name: Tomaszewska, K. Wioletta
name: Huang, Di-ying
name: Cai, Chen-yang
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Endomychidae
Rhomeocalpsua
Rhomeocalpsua torosa

description: Rhomeocalpsua torosa Li, Tomaszewska & Cai, sp. nov.
(Figs 1–5)
Material. Holotype, sex unknown, NIGP180054.
Etymology. The specific name refers to its distinctly enlarged antennal club.
Locality and horizon. Amber mine located near Noije Bum Village, Tanai Township, Myitkyina District, Kachin State, Myanmar; unnamed horizon, mid- Cretaceous, Upper Albian to Lower Cenomanian.
Diagnosis. As for the genus.
Description. Body relatively elongate, rather flattened, about 1.3 mm long, 0.5 mm wide, moderately densely setose.
Head prognathous, not retracted into prothorax. Eyes well developed, moderately protuberant, coarsely facetted, without interfacetal setae (Fig. 4A, D). Antennal grooves absent (Fig. 4B, D). Antennal sockets visible from above (Fig. 5C). Antennae (Figs 4C, D, 5F) composed of nine antennomeres; antennomere 2 oblong; antennomeres 3–6 moniliform; antennomeres 7–9 forming a distinct club; antennomere 7 strongly asymmetrical, short and strongly transverse; antennomere 8 strongly enlarged. Maxillary palps (Fig. 4B) 4-segmented, palpomere 1 smallest; palpomeres 2–4 narrowing progressively; palpomere 4 about as long as 2 and 3 combined, conical. Labial palps (Fig. 4B) 3-segmented, with apical palpomere apparently enlarged.
Pronotum (Fig. 3A) transverse, widest near the middle, narrower at base than elytral bases; lateral pronotal carinae complete, without raised margin (Fig. 5D); anterior angles not produced; disc without pits, sulci or carinae.
Elytra about 1.8 times as long as width combined, completely covering abdomen; sides weakly rounded; disc irregularly punctate; epipleura comparatively narrow, incomplete towards apices. Mesocoxal cavities circular, moderately widely separated, laterally broadly closed by meeting of meso- and metaventrites (Fig. 4E); mesotrochantins concealed; mesoventral process narrower than coxal cavity, narrowing between coxae towards apex, without apparent carinae or grooves (Fig. 4E). Mesometaventral junction as straight line with meso- and metaventrites contiguous (Fig. 4E). Metaventrite without postcoxal lines; postcoxal pits not apparent. Metacoxae (Fig. 4F) widely separated, transverse. Hind wings well developed.
Legs relatively long and slender. Trochanterofemoral joint oblique. Femora with deep and long groove (nearly throughout their length) for receiving tibiae (Fig. 4E, F). Tibiae without apical spurs, with short spines surrounding apex (Fig. 4H). Tarsi 3-3-3; tarsomeres simple (Fig. 4H, I). Pretarsal claws simple.
Abdomen (Fig. 4F, G) with six ventrites; ventrite 1 slightly longer than ventrite 2–4 combined, without postcoxal lines.
description: Published as part of Li, Yan-da, Tomaszewska, K. Wioletta, Huang, Di-ying & Cai, Chen-yang, 2022, Rhomeocalpsua torosa gen. et sp. nov., a unique lineage of Endomychidae from mid-Cretaceous Burmese amber (Coleoptera: Coccinelloidea), pp. 146-154 in Palaeoentomology 5 (2) on pages 148-149, DOI: 10.11646/palaeoentomology.5.2.7, http://zenodo.org/record/6530503