Rhomeocalpsua Li, Tomaszewska & Cai

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), Palaeoentomology 5 (2), pp. 146-154 : 148

Genus Rhomeocalpsua Li, Tomaszewska & Cai , gen. nov.

Type species. Rhomeocalpsua torosa sp. nov.

Etymology. The generic name is an anagram of Holoparamecus , a genus in Endomychidae : Merophysiinae . The name is feminine in gender.

Diagnosis. Body relatively elongate. Head with antennal sockets visible from above ( Fig. 5C ). Antennae composed of nine antennomeres, with club built of three antennomeres; antennomere 7 strongly asymmetrical; antennomere 8 strongly enlarged ( Figs 4C, D , 5F ). Apical labial palpomeres apparently enlarged ( Fig.4B ). Prothorax posteriorly constricted; pronotal disc without pits, sulci or carinae ( Fig. 3A ). Mesocoxal cavities broadly closed ( Fig. 4E ). Mesotrochantins concealed ( Fig. 4E ). Femora with deep and long grooves along inner side ( Fig. 4E, F ). Tarsi simple, 3-3-3 ( Fig. 4H, I ).

Figures

FIGURE 3. General habitus of Rhomeocalpsua torosa Li, Tomaszewska & Cai, gen. et sp. nov., holotype, NIGP180054, under confocal microscopy. A, Dorsal view. B, Ventral view. Scale bars = 500 μm.

FIGURE 4. Details of Rhomeocalpsua torosa Li, Tomaszewska & Cai, gen. et sp. nov., holotype, NIGP180054, under confocal microscopy. A, Head, dorsal view. B, Head, ventral view. C, Antenna, dorsal view. D, Antenna, ventral view. E, Mesothorax, ventral view. F, Abdominal base, ventral view. G, Abdominal apex, ventral view. H, Mesotarsus, ventral view. I, Metatarsus, dorsal view. Abbreviations: a1–9, antennomeres 1–9; cl, clypeus; lbp, labial palp; msc, mesocoxa; msf, mesofemur; mst1–3, mesotarsomeres 1–3; msv, mesoventrite; mtf, metafemur; mtt1–3, metatarsomeres 1–3; mtv, metaventrite; mxp, maxillary palp; v1–6, ventrites 1–6. Scale bars = 100 μm.

FIGURE 5. X-ray microtomographic reconstruction of Rhomeocalpsua torosa Li, Tomaszewska & Cai, gen. et sp. nov., holotype, NIGP180054. A, Dorsal view. B, Ventral view. C, Anterodorsal view. D, Lateral view. E, Posterior view. F, Antenna, rendered under “Sum along Ray” mode. Scale bars = 500 μm in A–E, 200 μm in F.