New findings of Cryptophagidae (Coleoptera: Clavicornia) from Baltic amber in the unbiased collection of the Paleontological Institute of RAS
Author
Lyubarsky, G. Yu.
Author
Perkovsky, E. E.
text
Russian Entomological Journal
2021
2021-09-30
30
3
282
287
http://dx.doi.org/10.15298/rusentj.30.3.05
journal article
10.15298/rusentj.30.3.05
0132-8069
13179717
A. groehni
Perkovsky et
Lyubarsky, 2014
Figs 5–6
.
MATERIAL.
PIN
964/1325, Baltic amber, Late Eocene. Specimen is deposited in the amber collection of the
PIN
RAS. Sex: unknown.
RE-DESCRIPTION. Length of body 1.0–
1.1 mm
, body elongate (
Figs 5–6
), moderately arched, head, pronotum, and elytra light-brown.Elytra slightly convex, covered with slightly curved long elevated pubescence.
Head transverse, of normal size, with hemispherical facetted eyes, strongly punctured. Antennae moderately long, with club reaching beyond base of pronotum, flagellomeres slightly elongate, antennomeres 1
st
, 2
nd
about 1.5 times as long as broad, 3
rd
slightly elongate, 4
th
and 6
th
antennomeres as long as broad, 5
th
1.5 times as long as broad, 7
th
, 8
th
subquadrate, 9
th
slightly transverse, 10
th
strongly transverse, 11
th
obliquely oval, antennomeres 9–11 equal in width. Antennae inserted under the lateral margin of the forehead, widely separated basally, antennal insertions close to the eyes.
Pronotum convex, not narrowed basally, slightly transverse, 1.2–1.5 times broader than long, broadest before the middle, moderately strongly and very densely punctured (distance between punctures equal to their diameter), a single puncture smaller than the diameter of the eye facet. Pubescence long and elevated. Sides finely margined, anterior edge weakly sinuate, without excision. Pronotum broadest before middle of its length. Side borders visible from above along the entire length. Lateral margin without callosity. Posterior corners right angled, basal edge lobed, strongly sinuate, basal groove shallow.
Figs 1–4. Photo of a new specimen of
M. sarnensis
from Baltic amber: 1 — dorsal view; 2 — lateral view; 3 — ventral view; 4 — head and pronotum, ventrolateral view.
Рис. 1–4. ВнеШний вид
M. sarnensis
иЗ балтийского ЯнтарЯ: 1 — габитус, сверху; 2 — габитус, сбоку; 3 — габитус,сниЗу; 4 — голова и переднеспинка, сниЗу и сбоку.
Scutellum small, transverse. Elytra short-oval, moderately convex, humeral corners rounded, maximum breadth of elytra in first third of their length, 1.6–1.7 times as long as wide and 2.5–2.7 times as long as thorax, punctuation slightly stronger and sparser than that on pronotum. Punctures in the basal part slightly stronger than those on the pronotal disk, and approximately 1.5–2 diameters apart from their lateral neighbours on an average; humeri not toothed.
Figs 5–6. Photo of a new specimen of
A. groehni
from Baltic amber: 5 — dorsal view; 6 — dorsolateral view.
Рис. 5–6. ВнеШний вид
A. groehni
иЗ балтийского ЯнтарЯ: 5 — сверху; 6 — сверху и сбоку.
REMARKS. Representatives of
Atomaria
are found in all biogeographic realms including 127 species in the Palaearctic Region [
Johnson et al., 2007
].
Atomaria groehni
differs from similar species with lateral margin of pronotum visible from above, such as
A. morio
Kolenati, 1846
and
A. versicolor
Erichson, 1846
, by small size and long elevated pubescence.
A. groehni
differs from species similar to
A. testacea
Stephens,
1830
in pronotum slightly narrowed basally and small size.
A. groehni
differs from most species of the genus in the structure of the antenna: the segments of the flagellum are subquadrate or slightly elongate.
Among the species of amber, it differs in a combination of characters: pronotum broadest before the middle of its length; elytra covered by long elevated pubescence; side borders of pronotum visible from above along the entire length.