New data on cockroaches of the subfamily Epilamprinae (Dictyoptera: Blaberidae) from India and Sri Lanka, with descriptions of new species and the genital complex of Aptera fusca (Thunberg, 1784)
Author
Anisyutkin, Leonid N.
Author
Yushkova, Olga V.
text
Zootaxa
2017
4236
1
41
64
journal article
36479
10.11646/zootaxa.4236.1.2
0f39b5c0-0af5-476f-8448-a02339cc1dfd
1175-5326
322014
23412386-CB17-49CA-9C47-BD71DD9C5372
Genus
Rhabdoblattella
Anisyutkin, 2000
Type species:
Rhabdoblattella cambodiensis
Anisyutkin, 2000
. By original designation.
Diagnosis.
The genus
Rhabdoblattella
is characterized by a unique complex of features: sexual dimorphism poorly marked; tegmina and wings completely developed or slightly abbreviated (as in
R
.
alexeevi
sp.nov.
—
Fig. 4A
); hind metatarsus longer than other segments combined, with the small apical euplantula along its lower margin, all segments of metatarsus with 2 more or less equal rows of spines along its lower margin; all euplantulae without spinules, partly bordered with rows of spines; claws symmetrical and very weakly serrated (visible at a large magnification); hypandrium asymmetrical, its caudal margin rounded and projected caudally, with a distinct median tooth directed upward (
Figs. 5
F, G, 6H, I,
m.t.
); right phallomere of the male genitalia with the caudal part of sclerite R1T (
Figs. 5
H, I, 6J, 11K,
c.p.R1T
) being separated from the cranial part R1T (
Figs. 5
H, I, 6J, 11K,
cr.p.R1T
), R3 triactinal with more or less developed branches (
Figs.
5
I, 6J, 11K), R2 fused with R5, R5 wide, platelike (
Figs. 5
H, 6J, 11K).
Notes.
In our opinion, the presence of a median tooth on the caudal margin of hypandrium and the structure of right phallomere described above can be considered the autapomorhies of the genus
Rhabdoblattella
. Other aforementioned characters that were listed in the original description (
Anisyutkin 2000
) are most likely to be plesiomorphic ones, as compared with other genera of the
Epilamprinae
.
A somewhat similar structure of the right phallomere can be observed in representatives of the genus
Africalolampra
Roth, 1995
. The structure of the male genitalia in the type species,
A
.
ehrmanni
Roth, 1995
, was briefly described by
Roth (1995)
. Yet, the right phallomeres of
A
.
erubescens
(
Gerstaecker, 1883
)
and
A
.
punctipennis
(
Saussure, 1895
)
are generally similar to those of
Rhabdoblattella
species (compare
Figs. 5
H, I, 6J and 11K and
Figs. 8
,
9
, 29
30 in
Anisyutkin 2016
).
It is possible that the plate-like sclerite of the right phallomere of
A
.
erubescens
and
A
.
punctipennis
(see
Figs. 8
,
9
, 29 30,
pl.s.
in
Anisyutkin 2016
) is homologous to the caudal part of sclerite R1T described in the present paper.
The genus
Rhabdoblattella
originally included five species from
Cambodia
(the
type
species),
Vietnam
,
Thailand
and
Burma
(
Anisyutkin 2000
):
R
.
cambodiensis
Anisyutkin, 2000
,
R
.
vietnamensis
Anisyutkin, 2000
,
R
.
delicata
Anisyutkin, 2000
,
R
.
annandalei
(
Shelford, 1909
)
and, probably,
R
.
kabakovi
(
Bey-Bienko, 1969
)
. Later,
Rhabdoblatta annamensis
(
Hanitsch, 1927
)
was transferred to the genus
Rhabdoblattella
by
Anisyutkin (2009)
. The male of
R
.
kabakovi
still remains unknown, so the generic assignment of this species is doubtful.
The representatives of
Rhabdoblattella
from
South India
and
Sri Lanka
described below (
R. alexeevi
sp.nov.
and
R
.
euptera
sp.nov.
) differ from the previously known
SE Asian
species by the presence of the well developed glands on the abdominal tergites (
Figs. 5
C, 6C, D). Additionally,
R. alexeevi
sp.nov.
differs from all other congeners in having the slightly abbreviated tegmina and wings (
Fig. 4A
), whereas
R. euptera
sp.nov.
can readily be distinguished from other congeners by the absence of the apical part of sclerite L2D (
Fig. 6
K, L). It should be noted that the abdominal tergal glands of
R. alexeevi
sp.nov.
and
R. euptera
sp.nov.
are located on different segments (compare
Figs. 5
C and 6C, D), which makes their homologation controversial.
The abdominal tergal glands in males play an important role in the sexual behavior of cockroaches (
Bell
et al
. 2007
,
Roth 1969
,
Roth & Willis 1954
). Consequently, the presence of these structures could indicate significant behavioural differences between new species (
R. alexeevi
sp.nov.
and
R. euptera
sp.nov.
)
and their congeners. On the other hand, the functionally similar tergal glands in Orthoptera can vary within the same genus (for instance, in Landrevinae—see
Gorochov 2016
). The shortening of tegmina and wings in
R. alexeevi
sp.nov.
obviously demonstrates a significant shift in its lifestyle as well. Unfortunately, at the present time it is impossible to comment on a functional significance of the apical part of sclerite L2D, which is absent from
R. euptera
sp.nov.
Taking into consideration that the available material is scanty and both species seem to differ morphologically from each other, it is better to postpone a formal description of a new genus/subgenus for
R. alexeevi
sp.nov.
and
R. euptera
sp.nov.