Microscydmus

Jałoszyński, Paweł & Perkovsky, Evgeny, 2016, Diversity of Scydmaeninae (Coleoptera: Staphylinidae) in Upper Eocene Rovno amber, Zootaxa 4157 (1), pp. 1-85 : 71

? Microscydmus sp. 3

( Figs 31 , 209–214 )

Material studied. Late Eocene of Europe , Rovno amber: sex unknown; inclusion in elongate, subrectangular prism of amber 14 mm long ( Fig. 31 ), collection number K-3657a ( SIZK).

Description. Body ( Figs 209–214 ) elongate, moderately slender and convex, light brown; BL 0.61 mm.

Head ( Figs 209–214 ) short and subtrapezoidal, broadest at eyes, HL 0.10 mm, HW 0.15 mm; vertex ( Fig. 212 ; vt) and frons ( Fig. 212 ; fr) confluent, weakly convex and together subtrapezoidal, strongly transverse; eyes large, oval, strongly convex; tempora distinctly shorter than eyes. Punctures on frons and vertex ( Fig. 212 ) fine but discernible, separated by spaces about twice as wide as diameters of punctures; setae poorly visible. Antennae ( Figs 209–214 ) slightly shorter than half BL, AnL about 0.27 mm, scape and pedicel strongly elongate, antennomeres III–VI each about as long as broad, VII distinctly transverse, VIII weakly transverse, IX and X distinctly transverse, XI much shorter than IX–X combined, about 1.2 × as long as broad, distinctly narrower than X and rounded at apex.

Pronotum ( Figs 209–210, 212–213 ) round, broadest near anterior fourth; PL 0.16 mm, PW 0.18 mm; anterior margin weakly emarginate; anterior pronotal corners weakly marked, broadly obtuse-angled and blunt; sides strongly rounded; posterior corners well-marked, obtuse-angled and blunt; posterior margin slightly angulate at middle; base with very short but distinct sublateral carinae ( Fig. 212 ; slc) and two pairs of small antebasal pits ( Fig. 212 ; abp). Punctures on pronotal disc ( Fig. 212 ) similar to those on head; setae ( Fig. 212 ) on disc poorly visible, on sides replaced by thick setae.

Elytra ( Figs 209–210, 212–213 ) elongate oval, moderately convex, partly obscured by cloudy amber and air bubbles, EL 0.35 mm, EW 0.28 mm, EI 1.27; punctures and setae not visible.

Legs ( Figs 211, 214 ) moderately long, slender, unmodified.

Remarks. This specimen has more characters exposed than the previous one, especially the head and ventral pterothoracic structures, but details of mesoventrite, basal elytral impressions and elytral foveae are not visible, and therefore it is only tentatively identified as Microscydmus .

Figures

FIGURES 21 – 34. Specimens of Rovno amber with inclusions of Scydmaeninae. K- 8972, Rovnoscydmus sp. specimen 8 (21); K- 3322, Rovnoscydmus sp. specimen 9 (22); K- 15548,? Rovnoscydmus sp. specimen 10 (23); K- 8971,? Rovnoscydmus sp. specimen 11 (24); K- 6045, Euconnus palaeogenus sp. n. (25); K- 9126, Euconnus sp. 1 (26); K- 24859,? Euconnus sp. 2 (27); K- 24302, Stenichnus proavus sp. n. (28); UA- 2216, Microscydmus sp. 1 (29); K- 6943,? Microscydmus sp. 2 (30); K- 3657 a,? Microscydmus sp. 3 (31); K- 6764,? Scydmoraphes sp. 1 (32); K- 6274, Glandulariini gen. & sp. indet. 1 (33); K- 7089, Glandulariini gen. & sp. indet. 2 (34).

FIGURES 209 – 214.? Microscydmus sp. 3 (K- 3657 a). Anterodorsal (209, 210, 212, 213) and ventral (211, 214) views. Abbreviations: abp, antebasal pit; bst, basisternal part of prosternum; bsti, basistipes; fr, frons; mn, mentum; mtvp, metaventral intercoxal process; mxp 2 – 4, maxillary palpomere II – IV; nr, ' neck' region; nss, notosternal suture; occ, occipital constriction; pg, pygidium; slc, sublateral carina; st 3 – 8, abdominal sternite III – VIII; tm, temple; v 3, metaventrite; vt, vertex.