Diversity of Scydmaeninae (Coleoptera: Staphylinidae) in Upper Eocene Rovno amber
Author
Jałoszyński, Paweł
Author
Perkovsky, Evgeny
text
Zootaxa
2016
4157
1
1
85
journal article
10.11646/zootaxa.4157.1.1
2389f078-1812-4b4e-826a-561cd7e46654
1175-5326
262413
6BF4514A-892F-499F-BC1E-B7920C7A00B0
Cephennomicrus
sp. 3
(
Figs 8
,
85–92
)
Material
studied.
Late Eocene
of
Europe
,
Rovno
amber:
sex unknown; inclusion in elongate irregular piece of amber
15 mm
long (
Fig. 8
), collection number K-27565 (
SIZK
).
Description.
Body (
Figs 85–92
) elongate and moderately strongly convex, brown; BL
0.75 mm
.
Head (
Figs 85–92
) broadest at eyes, HL
0.10 mm
, HW about
0.18 mm
; vertex (
Fig. 89
;
vt
) weakly convex and strongly transverse; frons (
Fig. 89
;
fr
) subtrapezoidal, flattened, posteriorly confluent with vertex; supraantennal tubercles weakly marked; eyes large, oval, strongly convex and relatively coarsely faceted. Antennae (
Figs 85–92
) distinctly shorter than half BL, AnL about
0.31 mm
, all antennomeres elongate, XI slightly shorter than IX–X combined, distinctly broader than X, about twice as long as broad and nearly symmetrical.
Pronotum (
Figs 85–92
) subrectangular, but its shape is difficult to assess in the studied specimen; PL
0.20 mm
, PW about
0.20 mm
; pronotal disc seems to be broadest near anterior third, sides sinuate; posterior pronotal corners distinct; posterior margin shallowly bisinuate with indistinct flattening in front of scutellum; base with two pairs of small and shallow antebasal pits (
Fig. 89
;
abp
) connected by narrow transverse antebasal groove (
Fig. 89
;
abg
). Punctures on pronotal disc very small but distinct, separated by spaces 2–3 × as wide as diameters of punctures; setae very short, moderately dense, suberect (
Figs 85–89
).
Elytra (
Figs 85–92
) elongate oval, moderately convex, EL
0.45 mm
, EW about
0.25 mm
, EI about 1.80; punctures slightly larger than those on pronotal disc; setae similar to those on pronotum (
Figs 85–86
,
89
).
Legs (
Figs 85–92
) moderately long, slender, unmodified; tibiae straight or weakly curved.
Remarks.
This is another well-preserved specimen of
Cephennomicrus
with perfectly exposed key generic characters, but the species is so unremarkable that presenting a reliable diagnosis is not possible. It is most similar to the specimen DU-32, described below as
Cephennomicrus
sp. 5. Both specimens share a similarly small body about
0.75 mm
in length, similar body form and fine punctures, and similar setae on the pronotum and elytra.
However, they clearly differ in proportions of body parts, especially in the elytral index (as far as it was possible to measure EL and EW in both specimens), and
Cephennomicrus
sp. 3 has all pronotal antebasal pits connected by a transverse groove, whereas
Cephennomicrus
sp. 5 has only the inner pair of pits connected. It seems justified to treat these specimens as belonging to two separate species, different from all other congeners found in
Rovno
amber.