Three new species of soldier beetles from Baltic amber (Coleoptera, Cantharidae)
Author
Fanti, Fabrizio
Author
Pankowski, Mary K.
text
Zootaxa
2018
2018-08-03
4455
3
513
524
journal article
29085
10.11646/zootaxa.4455.3.7
e805d477-ca64-4ea3-8990-285677f540b1
1175-5326
1457495
6B5ED1A9-FC34-4142-85AD-B35C73A427DE
Sucinorhagonycha samsockorum
FANTI & M. K. PANKOWSKI sp. nov.
(
Figs. 2–3
)
Description.
Adult, winged, elongated, rather robust. Male, defined on the basis of the last sternite very small, narrow, rounded at apex, and separated and away from the last tergite. Body length:
4.5 mm
; elytra:
3.3 mm
; antennae: approximately
2.5 mm
. Head black, elytra blackish to dark brown, pronotum with antennae and legs reddish to dark brown. Head very elongated and narrow, prognathous, completely exposed, wrinkled with shallow punctation and short setae. Eyes subelliptical, convex, inserted dorsally and near the sides of the head. Mandibles robust, elongated, slightly falciform, without teeth or denticles. Maxillary palps 4-segmented and unequal in length; first palpomere massive; second palpomere flat, robust, rounded and enlarged in the middle; third small, thin and short; last palpomere securiform, elongated, rounded externally, apically thin but with a bulbous tip. Labial palps 3-segmented, very elongated; first segment massive; second segment thin; last segment elongated, very slightly securiform with the apex robustly pointed. Antennae 12-segmented, inserted dorsally and between the eyes, very short, reaching and slightly surpassing the humeral zone, all segments pubescent along all margins; antennomere I (scape) filiform and robust, elongated, not club-shaped, slightly enlarged apically; antennomere II robust, short, 2.0 times shorter than scape, concave in the middle on the external side; antennomere III robust, slightly shorter than second article and not concave in the middle; antennomeres IV–V subequal, very slightly shorter than antennomere III, enlarged apically (dentate) on the external side; antennomere VI elongated, robust, approximately 1.5 times longer than antennomeres IV–V and not dentate on the external side; antennomere VII robust and the shortest, concave in the middle on the internal side; antennomere VIII filiform but slightly dentate at the external apex; antennomeres IX–XII filiform, unequal in length with the antennomere XII rounded at apex and the longest. Pronotum subquadrate, slightly longer than wide, very slightly wider than head, corners rounded, margins bordered, in the middle of the pronotum there is a large and very raised (evident) area slightly concave in the center, sides and margins flat after the raised area with shallow punctation and short pubescence. Scutellum not well visible. Elytra very elongated, slender, parallel-sided, completely covering the last abdominal segments, wider than pronotum, apex rounded, surface equipped with long and erected setae. Posterior wings completely covered by elytra. Metasternum blackish, punctate, elongated, posteriorly slightly rounded; sternites and tergites wide, punctate; last tergite short, wide and strongly bent at sides; last sternite small, narrow, rounded at apex. Anterior and median legs short, posterior legs longer; coxae massive, wide at base, elongated; trochanters elongated, posteriorly triangular; profemora strongly enlarged and slightly curved, meso- and metafemora thin; pro- and mesotibiae shorter than pro- and mesofemora, cylindrical, thin, with two spurs (one very short) and setae; metatibiae longer than metafemora, cylindrical, thin, with spurs and setae. Tarsi 5-segmented and with setae; pro– and mesotarsi with the first segment elongated, 1.5 times longer than second; metatarsi with the first tarsomere approximately 1.9 times longer than second; third tarsomere shorter than second and slightly enlarged apically; fourth tarsomere bilobed at sides with the lobes very long, curved and rounded at apex; fifth tarsomere elongated, thin; claws simple, long and without lobes or denticles.
Etymology.
Species named after Frank and Joanne Samsock, maternal grandparents of the second author, who worked hard, dedicated their lives to their family and were excellent role models for their children and grandchildren.
Holotype
.
Male, adult specimen included in Baltic amber, accession No.
USNM
PAL
712533 in
the
USNM
.
Type
locality.
Yantarny
settlement (formerly
Palmnicken
),
Sambian
(
Samland
)
Peninsula
,
Kaliningrad
Region,
Russia
.
FIGURE 2.
Sucinorhagonycha samsockorum
sp. nov.
in Baltic amber. A–B: Holotype, lateral views, scale bar = 1.0 mm. C: Holotype, detail of palps, scale bar = 0.4 mm. D: Holotype, detail of antenna, scale bar = 0.5 mm.
FIGURE 3.
Sucinorhagonycha samsockorum
sp. nov.
in Baltic amber. A: Holotype, detail of legs, scale bar = 0.5 mm. B: Holotype, detail of last sternites, scale bar = 0.5 mm.
Type
strata.
Baltic
amber,
Upper Eocene
,
Prussian Formation
(Priabonian).
Estimated
age: 37.8–33.9 Mya.
Syninclusions.
Many wood remains and masses of plant fragments (detritus).
Differential diagnosis.
Antennae with 12 antennomeres and the claws without lobes of the new species suggest that it belongs to the genus
Sucinorhagonycha
. (For more details, see the key below.) The genus is easily distinguishable from the fossils of the family
Cantharidae
Imhoff, 1856
with its 12-segmented antennae present only in
Cacomorphocerus
Schaufuss, 1892
(for the differences, see Discussion section below) and the extant Australian genus
Heteromastix
Boheman, 1858 (Subfamily
Dysmorphocerinae
Brancucci, 1980
), which also sometimes has 12 antennal articles (
Brancucci 1980
;
Fanti 2017c
), with the antennomeres X–XI strongly modified (
Brancucci 1980
;
Kuśka 1996
). Only one other species of
Sucinorhagonycha
has been described,
S. kulickae
Kuśka, 1996
, which is known on the basis of a male and a female found in different Baltic amber pieces (
Kuśka 1996
;
Kubisz 2000
;
Fanti 2017a
).
Sucinorhagonycha samsockorum
sp. nov.
differs from both sexes of
S. kulickae
because its antennal articles IV–V are slightly dentate (compared to filiform in
S. kulickae
), and because its pronotum is not transverse and has two evident central thickenings (while in
S. kulickae
the pronotum has a longitudinal central linear depression and protuberances on the sides). In addition, the male of
S. kulickae
has shorter antennomeres than
S. samsockorum
sp. nov.
Remarks.
The yellow amber piece has a spherical shape measuring
15x14
x
11 mm
and weighs
1.3 grams
. The inclusion is complete and well visible.