Baltimorda

Batelka, Jan, Rosová, Kateřina & Prokop, Jakub, 2023, Diversity and morphology of Eocene and Oligocene Mordellidae (Coleoptera), Acta Entomologica Musei Nationalis Pragae 63 (2), pp. 451-478 : 457

Baltimorda undescribed species B

( Figs 1G–I )

Material examined. One specimen, PřfUK94, obtained from Jonas Damzen (original number JDC 9688): Baltic amber.

Description. Body shape similar to Hoshihananomia Kôno, 1935 , cuticle matt, head subglobular, frons continuously convex, posterior edge of eye near posterior margin of head, elytra convex, metacoxa broad, pygidium long. Main characters: All eleven antennomeres cylindrical, antennomere XI acute at tip. Maxillary palpomeres not visible. Eyes elliptical, very finely faceted. Interfacetal setae not visible due to poor preservation. Form of scutellum indiscernible. Postero-lateral edges of pronotal disc obtuse. Elytra 3.0× as long as pronotal disc. Protarsomere I cylindrical; protarsomere IV flattened, deeply dilated. Protibia narrow, slightly curved, about 1.2× as long as protarsus. Mesotarsomere IV cylindrical, 0.75× as long as tarsomere III and V. Mesotibia 1.2× as long as respective tarsus. Metatibia only with preapical comb running parallel with row of apical setae. Outer tibial spur on metatibia as long as half of metatarsomere I; both metatibial spurs almost equal in length. Metatarsus without combs or ridges, ventral side of all metatarsomeres with spiniform setae. Pygidium 4.0× as long as hypopygium. Anterior edge of metanepisternum 2.5× as long as posterior edge, ventral edge 6.5× as long as posterior edge. Metakatepisternum not delimited. Pretarsal claws simple, without visible teeth. Tip of pygidium with few dark acute setae.

Lengths (in mm): pronotal disc = 0.86, elytra = 2.7, mesotibia = 0.7, metatarsomere I = 0.5, pygidium = 1.2.

Differential diagnosis. This specimen is the second species of Baltic Mordellini known to lack dorsolateral ridge on the metatibia. In addition to the different habitus, there are also some evident differences in the measurements of this species B and Succimorda rubromaculata Kubisz, 2001 (see the Key below). The comparison with extant Mordellini has to wait until this tribe is reviewed.

Figures

Figs 1. Mordellidae, Baltic amber.A – Baltistena sp., SDEI-Amb-000644, hind leg. B – Baltimorda scheelei (Ermisch, 1941), holotype, hind leg. C–F – Baltimorda, undescribed speciesA, PřfUK71: C – habitus; D – head and thorax; E – hind leg (black arrows marking fine dorsolateral ridge); F – pretarsal claws. G–I – Baltimorda, undescribed species B, PřfUK94: G – habitus; H – hind legs; I – metatarsus. Scale bars: A, E, H, I – 0.2 mm; B, D, – 0.3 mm; C, G – 0.5 mm; F – 0.05 mm.