Taxonomy of ' Euconnus complex'. Part XXIV. Intermediate forms between Psomophus, Eupentarius and Euconnus s. str. in the East Palaearctic fauna unify problematic subgenera (Coleoptera, Staphylinidae, Scydmaeninae)
Author
Jałoszyński, Paweł
text
Zootaxa
2022
2022-10-06
5194
3
343
391
journal article
160068
10.11646/zootaxa.5194.3.2
37029023-13d3-4f8b-aa2f-675882e19a2f
1175-5326
7154500
92DCC339-93BA-4C64-8035-7940F10F26DC
Euconnus
(s. str.)
multiinsularis
sp. n.
(
Figs 6–18
,
109
)
Type material studied.
Holotype
(
Japan
:
Kagoshima Prefecture
: Takarajima Is.):
♂
, three labels: “Arakizaki / Takarajima Is. / Tokara, Ryukyu” [white, printed], “
22. iii. 1992
/
S. Nomura
leg.” [white, printed], “
EUCONNUS
s. str.
/
multiinsularis
m. /
P. Jałoszyński
, ’22 /
HOLOTYPUS
” [red, printed] (
NSMT
)
.
Paratypes
(9 exx):
Takarajima Is.
:
♂
, same data as for holotype;
Tokunoshima Is.
:
2 ♂♂
, “Yonama / Tokunoshima Is. /
Kagoshima Pref.
” [white, printed], “
4. v. 1988
/
S. Nomura
leg.” [white, printed];
Okinawa-jima Is.
:
1 ♂
,
1♀
, “[
Okinawa
: RYUKYU] /
Mt. Nishimedake
/
360m
,
Kunigami
/
19.X. 1987
/
M. Sakai
leg.” [white, printed], “
Leaf
litter” [white with black frame, printed];
1 ♂
, “
Yona
, kunigami /
Okinawa Pref.
” [white, printed], “
15. iii. 1985
/
S. Nomura
leg.” [white, printed];
2 ♀♀
, “(RYUKYUS) /
Mt. Yonahadake
/
Okinawa
Island
/
6. X. 1978
/ K.
Ishikawa
” [white, printed], ”collected from / soil by using /
Berlese funnel
” [white, printed];
Amami Ôshima Is.
:
♂
, “
JAPAN
, KAGOSHIMA Pref. /
Amami Ôshima
,
Yui-dake
/ 25-28-2004,
white pan trap
/
Toshiharu Mita
leg.” [white, printed]
.
Paratypes
in NSMT, EUMJ and cPJ, all with yellow “
PARATYPUS
” labels similar to that with
holotype
.
Diagnosis.
Antennal club clearly trimerous and slender; head round; pronotum subconical and broadest near base but only moderately narrowing anterad, with one pair of antebasal pits connected by distinct transverse groove and with distinct sublateral carinae; protibiae in males strongly bent mesad in apical regions; aedeagus conspicuously strongly, darkly sclerotized and strongly elongate, endophallic sclerites not fused into ring-like structure, with bulbous portion nearly parallel-sided or broadest in distal third and with relatively small dorsal apical plate, which in ventral view is only slightly elongate, in proximal half weakly narrowing distad, and in distal half abruptly narrowing to form subtrapezoidal and truncate apex.
FIGURES 6‒10.
Euconnus multiinsularis
sp. n.
, male (Takarajima). Dorsal habitus (6); aedeagus in ventral (7, 9) and lateral (8, 10) views.
FIGURES 11‒18.
Euconnus multiinsularis
sp. n.
, examples of aedeagus from specimens collected on Amami Ôshima (11‒12), Tokunoshima (13‒14), and Okinawa-jima (15‒18) islands.
Description.
Body of male (
Fig. 6
) elongate, moderately convex; pigmentation moderately dark umbra brown, legs and palps distinctly lighter, antennal clubs not infuscate; body covered with setae distinctly lighter than cuticle; BL
1.28–1.40 mm
.
Head broadest at eyes, indistinctly transverse, HL
0.28 mm
, HW
0.28–0.30 mm
; tempora in dorsal view about 1.5 × as long as eyes, behind eyes strongly and evenly convergent posterad, posterior margin of vertex weakly arcuate, not bulging posterodorsad. Frons and vertex with unremarkable, fine punctures, glossy; setae sparse and suberect, tempora with sparse thick bristles. Antennae slender, with loosely assembled and slender trimerous club, AnL
0.58–0.63 mm
, scape and pedicel each elongate, antennomeres 3–8 each indistinctly longer than wide, 9–11 enlarged, 9 and 10 each indistinctly transverse, 11 distinctly shorter than 9 and 10 combined, about 1.5 × as long as broad.
Pronotum subconical and broadest shortly in front of base, moderately narrowing anterad; PL
0.30–0.34 mm
, PW
0.33–0.35 mm
. Sides weakly rounded, base with one pair of small but distinct pits connected by transverse groove, and with distinct, sharply marked sublateral carinae. Punctures and setae on disc similar to those on frons and vertex; sides of pronotum with moderately dense thick bristles.
Elytra together oval, broadest distinctly in front of middle; EL
0.70–0.80 mm
, EW
0.53–0.55 mm
, EI 1.33–1.45; humeral calli distinct and slightly elongate, mesally demarcated by elongate impressions; elytral apices separately rounded. Punctures distinct but shallow, those near median area of both elytra separated by spaces slightly wider than diameters of punctures; setae sparse but much longer than those on pronotal disc, suberect.
Legs slender, protibiae modified, with apical regions strongly bent mesad.
Aedeagus (
Figs 7–18
) strongly elongate and strongly sclerotized, AeL
0.33 mm
; median lobe in ventral view broadest in distal third or nearly parallel-sided, in lateral view strongly curved, dorsal apical plate in ventral view elongate, with sides weakly converging distad in proximal half, rapidly narrowed in distal region to form subtrapezoidal and truncate apex; endophallus lacking ring-like sclerotized structure, poorly demarcated and situated in apical region. Parameres slender but short, not reaching apex of median lobe, each with two long apical setae. Some variability in the shape of median lobe was found among specimens collected on various islands (
Figs 7–18
), but differences are minor and seem to represent only interspecific variation.
Female. Similar to male but with straight, unmodified distal region of protibiae. BL
1.28–1.34 mm
; HL
0.28 mm
, HW
0.30 mm
, AnL
0.58–0.60 mm
; PL
0.30–0.31 mm
, PW
0.33–0.35 mm
; EL
0.70–0.75 mm
, EW
0.55–0.60 mm
, EI 1.25–1.27.
Distribution.
Islands of northern and central Ryūkyū:Takarajima, Tokunoshima,Amami Ôshima, and Okinawajima (
Fig. 109
).
Etymology.
The adjective
multiinsularis
refers to a distribution on several islands.
Remarks.
Although this species externally resembles closely
E. nuperus
,
E. debilis
and
E. chinensis
, it can be easily identified by its unique, unusually elongate and slender aedeagus.Aedeagi of specimens collected on different islands were studied (
Figs 11–18
) and only small differences were found, attributable to intraspecific variability. No external characters differ among populations inhabiting different islands. Females can be distinguished from the three similar congeners by slightly longer and slenderer body.
Interestingly, the northern
Euconnus debilis
and the southern
E. multiinsularis
co-occur on the small island of Takarajima, which represents the southernmost known locality for the former, and the northernmost for the latter (
Fig. 109
).