Review of Scydmaenus (Geoscydmaenus) of Madagascar (Coleoptera, Staphylinidae, Scydmaeninae)
Author
Jałoszyński, Paweł
text
Zootaxa
2016
4205
3
265
274
journal article
10.11646/zootaxa.4205.3.6
d8d24aba-900e-4dcc-97cd-adb094ebe3ca
1175-5326
194329
66FB30C3-66BC-4D79-9361-03F5C9F22498
Scydmaenus
(
Geoscydmaenus
)
madagassicus
Franz
(
Figs 2, 5–10
,
13, 15
,
19–21
,
24–25
)
Scydmaenus
(
Geoscydmaenus
)
madagassicus
Franz, 1986
: 374
, fig. 342.
FIGURES 16–21.
Scydmaenus
(
Geoscydmaenus
)
of Madagascar.
Scydmaenus isaloensis
Franz
(16–18) and
Sc. madagassicus
Franz
(19–21). Aedeagus in ventral (16, 19) and lateral (17–18, 20) view (with partly exserted flagellum in Fig. 18); spermatheca (21).
FIGURES 22–25.
Scydmaenus
(
Geoscydmaenus
)
of Madagascar.
Scydmaenus isaloensis
Franz
(22–23) and
Sc.
madagassicus
Franz
(24–25). Aedeagus in ventral (22, 24) and lateral (23, 25) views.
Type
material.
Holotype
(
MADAGASCAR
)
:
♂
, two labels (Fig.): "S-Madagaskar /
Forêt de Sakahara
/ lg.
H.Franz
1969" [white, printed] with "
Mg
18" handwritten in blue on the reverse side;
Scydmaenus
/ (
Geoscydmaenus
) /
madagassicus
m. / det.
H.Franz
" [white, handwritten and printed]; "
♂
" [white, printed]; "
Typus
" [red, handwritten] (
NHMW
)
.
Paratypes
:
23 exx., same data as for
holotype
(
NHMW
)
.
Revised diagnosis.
Head broadest near posterior third of vertex, moderately narrowing anteriorly; profemur of male with clavate part strongly convex dorsally but weakly ventrally, with short and straight ventral projection located between proximal third and middle; protibia of male gradually broadened distally and nearly straight; aedeagus with indistinct median apical notch not separating lateral lobes.
Redescription.
Male very similar to
Sc. isaloensis
, only differences and measurements are given below. BL
0.80–0.83 mm
(mean
0.81 mm
).
Head (
Figs 5–8
) broadest near posterior third of vertex and weakly narrowing anteriorly, in most specimens large punctures covering nearly entire surface of frons and vertex, but often small median area remains almost impunctate; HL
0.13–0.14 mm
(mean
0.13 mm
), HW
0.15 mm
; AnL 0.3 9–0.43 (mean
0.41 mm
). Antenna (
Fig. 13
) slightly longer in relation to body length than that of
Sc. isaloensis
, with distinctly elongate antennomere VI, slightly elongate antennomere IX and distinctly asymmetrical antennomeres VI–VIII.
Pronotum (
Fig. 5
) of the same shape and proportions as that in
Sc. isaloensis
; PL
0.20–0.21 mm
(mean
0.21 mm
), PW
0.18–0.20 mm
(mean
0.19 mm
).
Elytra as in
Sc. isaloensis
; EL
0.48 mm
, EW
0.28–0.30 mm
(mean
0.28 mm
), EI 1.58–1.73.
Legs (
Fig. 15
) with profemur less thickened in distal third, its clavate part strongly convex dorsally but only weakly so ventrally; ventral femoral projection short, straight and perpendicular to the long axis of femur, not accompanied by long seta and with evenly rounded apex; protibia (
Fig. 15
) weakly and gradually thickened, almost straight.
Aedeagus (
Figs 19–20
,
24–25
) elongate, AeL
0.25 mm
; median lobe in ventral view with indistinctly demarcated apical portion, apex with indistinct median notch not separating lateral lobes.
Female.
Similar to male, except for distinctly more slender profemora lacking ventral projections. BL
0.79– 0.84 mm
(mean
0.82 mm
); HL
0.13–0.14 mm
(mean
0.13 mm
), HW
0.15–0.16 mm
(mean
0.16 mm
), AnL
0.38– 0.43 mm
(mean
0.41 mm
); PL
0.21–0.23 mm
(mean
0.22 mm
), PW
0.20 mm
; EL
0.45–0.48 mm
(mean
0.46 mm
), EW
0.28–0.30 mm
(mean
0.28 mm
), EI 1.58–1.73.
Distribution.
South-western
Madagascar
, Atsimo-Andrefana Region.
Remarks.
Franz (1986)
stated that
Sc. madagassicus
had the head more elongate than
Sc. isaloensis
; the pronotum in relation to the head broader than that in
Sc. isaloensis
; and the profemur of male lacking tooth.
Moreover, the aedeagus of this species was described as "völlig anders gebaut" ("entirely differently built"), but the aedeagus of
Sc. isaloensis
was illustrated only in the lateral view, whereas that of
Sc. madagassicus
only in the dorsal view, so it is not possible to see any fundamental differences (especially knowing that Franz frequently illustrated aedeagi in a rather schematic and inaccurate way). Examination of the
type
series of both species revealed that the head is equally long and broad in
Sc. isaloensis
and
Sc. madagassicus
; the species do not differ in the width of pronotum in relation to the width of head; and males of both species have the ventral femoral tooth. Consequently, all external morphological characters used by Franz to define these species have been misinterpreted, and his illustrations of aedeagi cannot be used to find any differences. Useful differences in the shape of profemora and tibiae, in the shape of the head; in the punctures on frons and vertex; and in proportions and shapes of antennomeres, were found during the present study; also the aedeagi truly differ in the general shape, although not so much in internal endophallic structures. Clearly these are closely related, but easily identifiable species.