A taxonomic study on the Bornean and Philippines Sword-tailed Crickets in the genus Rhicnogryllus Chopard, 1925 (Orthoptera: Trgonidiidae; Trigonidiinae)
Author
Tan, Ming Kai
Institut de Systématique, Evolution et Biodiversité (ISYEB), Muséum national d’Histoire naturelle
orthoptera.mingkai@gmail.com
Author
Baroga-Barbecho, Jessica B.
Office of the Vice Chancellor for Research and Extension, University of the Philippines Los Baños, College
Author
Japir, Razy
Forest Research Centre (Sepilok), Sabah Forestry Department
Author
Chung, Arthur Y. C.
Forest Research Centre (Sepilok), Sabah Forestry Department
Author
Wahab, Rodzay Bin Haji Abdul
Institute for Biodiversity and Environmental Research, Universiti Brunei Darussalam, Jalan Universiti
Author
Yap, Sheryl A.
Institute of Weed Science, Entomology, and Plant Pathology, College of Agriculture and Food Science, University of the Philippines Los Baños, College. Museum of Natural History, University of the Philippines Los Baños, College.
text
Zootaxa
2020
2020-04-09
4763
2
217
230
journal article
10.11646/zootaxa.4763.2.5
85439034-f26e-40e2-ba2a-f5654eb352f1
1175-5334
3758250
urn:lsid:zoobank.org:pub:D179A5F1-C594-4B42-938E-3F8A2734BA84
Rhicnogryllus bipunctatus
Ingrisch, 1987
Figs. 3
,
6
Rhicnogryllus bipunctatus
—
Ingrisch, 1987: 176
> original description;
Tan et al., 2019c: 306
(record in Sandakan)
Rhicnogryllus eximius
—Chopard, in litt.
Material examined.
Male
holotype
(only images examined),
East
Malaysia
,
Sarawak
,
Batu Niah
, 3/4
August
1984, coll.
S. Ingrisch
(
SMFD
).
Paratype
of
Rhicnogryllus eximius
(
1 male
, MNHN-EO-ENSIF6583, only images examined),
East
Malaysia
,
Sabah
(“North Borneo”), Sandakan,
24 July 1927
(
MNHN
).
1 female
(BRU.19.61),
Brunei Darussalam
,
Belait District
, Teraja,
N4.28487
,
E114.41817
,
28.7±74.9 m
.a.s.l., 1906 hours,
2 March 2019
, coll. M. K. Tan & H. Yeo;
1 male
(BRU.19.68) and
1 female
(BRU.19.69), same locality, Wasai Wong Kadir Recreational Park,
N4.3421
,
E114.44655
, 23.0±
6.6 m
.a.s.l., 1639 hours,
7 July 2019
, coll. M. K. Tan & H. Yeo (
ZRC
and
UBDM
).
FIGURE 3.
Live habitus of
Rhicnogryllus bipunctatus
female from Sandakan, Sabah (locality of
R. eximius
sensu Chopard
) (A) and male from Brunei Darussalam (B).
4 males
(SDK.19.42–45),
East
Malaysia
,
Sabah
, Sandakan, Ulu Dusun,
N5.78364
–5.78379
,
E117.76051
– 117.76094, 38.3–41.6±
5.1–6.7 m
.a.s.l.,
1008–1038
hours,
10 January 2019
, coll. M. K. Tan, R. Japir, M. Binti & J. L. Yukang;
1 female
(SDK.19.67), same locality, Sepilok, Rainforest Discovery Centre,
N5.87575
,
E117.94059
, 54.5±
6.3 m
.a.s.l., 0946 hours,
1 October 2019
, coll. M. K. Tan & J. L. Yukang (
ZRC
and
FRC
).
Type details.
Male
holotype
, Borneo:
Sarawak
: Batu Niah (
SMFD
)
Remarks.
A male “
paratype
” of
Rhicnogryllus eximius
Chopard
collected from Sandakan was found in MNHN and it resembles
R. bipunctatus
as described by
Ingrisch (1987)
as well as the recent specimens collected from
Brunei
and Sandakan. However, we could not find any publication of the description associated with
R. eximius
and concluded that Chopard may not have described this species despite specifying the type specimens until
Ingrisch (1987)
described the exact same species from
Sarawak
. Thus, we consider Chopard’s
R. eximius
as a synonym of
R. bipunctatus
.
Ingrisch (1987)
provided a comprehensive description of the male, but the female was not known at that time.
Diagnosis.
This species differs from congeners by the combination of these characters: generally black colouration, with dorsum of head with a broad white line connecting the eyes; antennal scapus red brown; posterior femora white with two black bands, posterior tibia red brown; tarsal segments whitish; tegmen with a big, round, white spot at the base; supra-anal plate and base of cerci white; and male genitalia (
Fig. 3
). The male genitalia is also similar to that of
Trigonidium
but differs by virga as long as rachis (usually shorter than rachis in
Trigonidium
).
Distribution.
Borneo: Sandakan (
Sabah
); Batu Niah (
Sarawak
);
Brunei Darussalam
Male genitalia characteristics (
Figs. 6
A–C).
Pseudepiphallus separated into two lateral parts joined by an anterior sclerotized bridge; bridge narrow and gently curved. Posterior apex of pseudepiphallus forming thin and long, sclerotized lophi; lophus feebly curved inwards, with inner margin with 4–5 tooth-like spines, with apex forming a tooth; posterior edges of pseudepiphallic sclerite with a stout, angular lobule in the middle, lobule with stout teeth along margin. Pseudepiphallic parameres elongated heart-shaped, not exceeding apex of pseudepiphallic lobules. Ectophallic fold large forming an elongated sclerotized virga with acute apex. Ectophallic apodeme weakly sclerotized but long. Ramus straight. Endophallic sclerite elongated along dorsal cavity, with a median crest, with lamella of apodemes appearing flat and broad.
Female description.
Habitus similar to males, does not exhibit sexual dimorphism. Supra-anal plate with basal half black, with a longitudinal groove and angularly emarginated at the apex; epiproct with broad and stout, with obtuse apex, white. Subgenital plate stout, distinctly broader than wide, with anterior margin straight, apex narrowly excised in the middle; basal part black, thereafter white. Ovipositor not surpassing cerci; basal third with margins straight and smooth; apical third with dorsal margin distinctly denticulated, ventral margin also denticulated but less dense and only towards the apex. Ventral valves slightly longer than dorsal valves.
Natural history.
This species tends to be found among foliage of shrubs or low-lying vegetation in the understory of relatively disturbed forest and/or forest edge (at least in Sandakan and
Brunei
). Ulu Dusun and Rainforest Discovery Centre (Sandakan) as well as Teraja and Wasai Wong Kadir Recreational Park (
Brunei
) typically are disturbed forest with the presence of human traffic. The species can be found active in both day and night.