Taxonomic notes on toad bug genus Nerthra (Hemiptera: Heteroptera: Gelastocoridae) with description of a new species from Bonaire and Curaçao
Author
Nieser, Nico
Author
Chen, Ping-ping
Author
Caspers, Max
text
Acta Entomologica Musei Nationalis Pragae
2024
2024-05-08
64
1
33
46
http://dx.doi.org/10.37520/aemnp.2024.004
journal article
10.37520/aemnp.2024.004
1804-6487
11449763
E328DCDF-C5AB-4FAC-846D-D4DC552D5835
Nerthra occidua
Todd, 1959
(
Figs 17
,
31–37
,
39
)
Nerthra occidua
Todd, 1959: 71
(original description).
Nerthra lurida
Todd, 1959: 72
(original description),
syn. nov.
Type material examined.
Nerthra lurida
:
HOLOTYPE
:
♀
,
INDONESIA
:
SULAWESI SELATAN
(
Fig. 39
):
Rantepao
,
Nanggala
,
900 m
,
vii.1937
, leg.
Drescher
(
RMNH
).
Additional material examined.
INDONESIA
:
SULAWESI TENGAH
:
Lore Lindu NP, Sopu River Pools,
930 m
a.s.l.,
6.xii.1985
, leg. J. Krikken & J. van Tol,
1 ♀
, det. P. Lindskog (identified by comparing with
type
) (
RMNH
); Lore Lindu NP, Sopu River Pools,
930 m
a.s.l.,
6.xii.1985
, leg. J. Krikken & J. van Tol,
2 ♀♀
(
RMNH
); Lore Lidu N.P., Dongi Dongi shelter,
940 m
a.s.l.,
4.‒8.xii.1985
, multistratified evergreen forest, 2 fish traps, leg. J. Krikken,
3 ♀♀
(
NCTN
); same, garage,
950 m
a.s.l.,
4.‒9. xii.1985
, multistratified evergreen forest, 4 dung traps, leg. J. Krikken, 4 33
7 ♀♀
, 1 L (instar 5) (2 33
2 ♀♀
NCTN
, 2 33
5 ♀♀
RMNH
); Lore Lindu NP Dongi Dongi shelter,
940 m
a.s.l.,
4.‒8.xii.1985
, multistratified evergreen forest, 2 human excr[ement] traps, leg. J. Krikken, 1 3
1 ♀
, 3 L (instar 4) (
RMNH
); Lore Lindu NP, Danau Tambing forest,
1600 m
a.s.l.,
5.‒09.xii.1985
, multistratified evergreen forest, 4 human excr[ement] traps, leg. J. Krikken,
1 ♀
(
RMNH
).
Discussion
(
Fig. 39
).
TODD (1959)
described two species in the same paper, namely
N. occidua
(
holotype
male, deposited in Museum für Naturkunde, Berlin) and
N. lurida
(
holotype
female, deposited in RMNH), and mentioned a number of small differences between them. Both the species were collected from
Sulawesi
but each of them was based on an unique specimen of different sex, therefore comparison of male genitalia was not possible.
Nerthra occidua
was distinguished from
N. lurida
by a wider head (equal to combined length of pronotum and scutellum), the front of the head rounded, scutellum moderate with median and basal portions depressed, and the pronotum and abdomen wider. According to the drawing given by
TODD (1959: 63
, figs 14–15), little difference can be seen except that
N. lurida
is very slightly broader.
After the work of Todd, additional gelastocorids were collected in
Sulawesi
by Dr. J. Krikken and other colleagues of RMNH during the Project Wallace in 1985. It is interesting to note that the specimens were collected in pitfalls baited with excrement or rotting fish as collateral catch of research on dung beetles. There are other records of species of
Nerthra
found in cow dung: the Neotropical
N. manni
Todd, 1955
(
LAUCK & WHEATCROFT 1958
) and
N. raptoria
,
specimens in RMNH (see above). This does not necessarily imply that these species eat dung, but more likely the bugs are able to find prey near this kind of smell. We have compared the later samples with the
holotype
of
N. lurida
. Running the key of
TODD (1959: 62)
, the males of this series from
Sulawesi
(
Figs 30–32
) can be identified as
N. occidua
by the shape of paramere (
TODD 1959: 69
, Fig. 45). However, the front of the head (
Figs 31–34
) is flat and its width is less than the combined length of the pronotum and the scutellum (4.5 / 5.0), which would agree with
N. lurida
according to
TODD (1959)
. In some females, the front of the head is slightly convex (
Figs 31–34
), but in most, as in
N. occidua
, the width of head is less than the length of the pronotum and the scutellum combined (4.7 / 5.1) as in
N. lurida
. The scutellum itself is not elevated but all three tumescences are strongly elevated in both males and females. Therefore, we conclude that
N. occidua
and
N. lurida
refer to the same species. We choose
N. occidua
as the valid name because it was described on a male, and
N. lurida
becomes its junior subjective synonym.