First fossil representatives of Pharaxonothinae Crowson (Coleoptera: Erotylidae): indirect evidence for cycads existence in Baltic amber forest
Author
Alekseev, Vitalii I.
Author
Bukejs, Andris
text
Zootaxa
2017
2017-10-19
4337
3
413
422
journal article
31798
10.11646/zootaxa.4337.3.6
0fc0b3f0-dfbc-4f93-98f7-ba3d8c54670f
1175-5326
1025008
4F937323-3789-420A-A4FD-E2783EFF4761
Pharaxonothinae
gen. indet.
(
Figs 10–11
)
Material examined.
Specimen No 578-1 [
CCHH
], adult, sex unknown;
Baltic
amber,
Yantarny
,
Kaliningrad
region,
Russia
. Almost complete beetle (left metatarsomeres 2–5 lost) embedded in medium-sized, elongate, transparent, orange amber piece with approximate dimensions 35 × 14 ×
6 mm
.
Body
length of beetle is
3.3 mm
.
Syninclusions
are represented by one fragment of
Nematocera
(
Chironomidae
?) and numerous small detritus particles.
The
amber piece was apparently subjected to thermal and high-pressure processing in an autoclave, based on what is evident from characters mentioned by
Hoffeins (2012)
.
The
right side of elytra and pronotum is fragmented and destroyed, the right antenna is partially disintegrated and the head (especially clypeal and frontal area) is strongly deformed.
The
dark monochrome body colour of the specimen may also be a result of the discolouration during “improving” of the amber piece.
Note.
The specimen belongs to an undescribed species of
Pharaxonothinae
, either to
Pharaxonotha
or to the morphologically close
Cycadophila
. It differs from
C. mumia
sp. nov.
in the finely bordered elytral base, acute anterior pronotal angles, smaller body size, elytral punctation in rows laterally, and dark body colour. The main characters of the subfamily and
Pharaxonotha
(
sensu lato
) (e.g. glabrous body; elytra with non-impressed punctate rows and shortened scutellary striole; pro- and mesocoxal cavities open; narrow pronotal posterolateral sulci; abdomen without metacoxal lines; 11-segmented antennae with a 3-segmented antennal club not flattened; transverse scutellar shield; tarsal formula 5-5-5) are clearly visible on the specimen. The beetle is probably not conspecific with
Cycadophila mumia
sp. nov.
, but it cannot be named and formally described at present due to poor preservation.