A Baltic amber species of the diving beetle genus Coptotomus Say, 1830 (Coleoptera Dytiscidae: Coptotominae) Author Hendrich, Lars SNSB-Zoologische Staatssammlung, Mu ̈ nchhausenstrasse 21, D- 81247 Mu ̈ nchen, Germany Author Balke, Michael SNSB-Zoologische Staatssammlung, Mu ̈ nchhausenstrasse 21, D- 81247 Mu ̈ nchen, Germany text Zootaxa 2020 2020-12-15 4895 2 285 290 journal article 9266 10.11646/zootaxa.4895.2.7 33852167-3335-4c92-b513-5f3f4b83c23f 1175-5326 4322575 53E32A6A-00EE-47C3-9761-968DAA73BC4F Genus Coptotomus Say, 1830 Type species: Coptotomus serripalpus Say, 1830: 30 . Diagnosis. Medium sized species of Dytiscidae (total length 5.2–8.6 mm ), dorsally with fine, dense puncturation; females with punctures of pronotum and base of elytron elongated into short, fine strioles, or in the Baltic species with longitudinal striae on pronotum and elytron. Colour yellow to pale red with dorsal surface variously marked ( Fig. 3A ) ( Larson et al. 2000 ). Miller & Bergsten (2016) provided the following diagnostic character combination: 1) pronotum with well developed lateral bead; 2) metacoxal lobes large and rounded with metacoxal lines not closely approximated; 3) prosternum and prosternal process in same plane; 4) pro- and mesotarsi distinctly pentamerous; 5) scutellum visible; 6) metatarsomeres I–IV with lobed ventral apical angles; 7) apical palpomere of both, maxillary and labial palps, distinctly bifid and 8) metatarsal claws subequal in length in both sexes.