Spotted males, uniform females and the lowest chromosome number in Tettigoniids recorded: Review of the genus Gonatoxia Karsch (Orthoptera, Phaneropterinae)
Author
Hemp, Claudia
Author
Heller, Klaus-Gerhard
Author
Warchalowska-Śliwa, Elzbieta
Author
Hemp, Andreas
text
Deutsche Entomologische Zeitschrift
2016
63
2
271
286
http://dx.doi.org/10.3897/dez.63.10799
journal article
http://dx.doi.org/10.3897/dez.63.10799
1860-1324-2-271
3F2DB40D1E9140619323983DAC0D862B
Gonatoxia furcata C. Hemp
sp. n.
Holotype male.
Tanzania, Morogoro District, Udzungwa Mountains, National Park Headquarters, Mangula Gate, 300 m, lowland wet forest, July 2015. Depository MfN.
Paratype female, same data as holotype but March 2015. Depository MfN.
Further paratype material.
3 females, same data as holotype, May and June 2016 (collection C Hemp). 1 male (in alcohol), Tanzania, Iringa Region, Mufindi District, Udzungwa Scarp Forest Reserve,
08°31.5'S
35°53.9'E
, 750 m, March 1996, McKamey et al. leg., depository ZMUC.
Diagnosis.
Females of
Gonatoxia maculata
,
Gonatoxia immaculata
and
Gonatoxia furcata
sp. n. are very similar. Differences are seen in the general coloration especially when specimens are alive.
Gonatoxia maculata
and
Gonatoxia helleri
sp. n. females are of lighter green colour while those of
Gonatoxia immaculata
and especially
Gonatoxia furcata
sp. n. are darker green and the tegmina shiny (Fig. 2B, C, D). The subgenital plate in
Gonatoxia maculata
is not as broad as those of
Gonatoxia helleri
sp. n.,
Gonatoxia immaculata
and
Gonatoxia furcata
sp. n. (Fig. 9A, B, C, D) but the differences are not very pronounced. Lateral at the base of the ovipositors a bowl-like structure is present in all
Gonatoxia
species (arrows Fig. 7). In
Gonatoxia maculata
this bowl-like structure is large and more deeply excavated than in
Gonatoxia immaculata
(Fig. 8A). In
Gonatoxia furcata
sp. n. inside the
"bowl"
a hump is located at the upper part and the lower margin is not hairy as in the other two species. The bowl-like structure in
Gonatoxia helleri
sp. n. is very shallow and not as setose (Fig. 8B). Further
Gonatoxia immaculata
females are smaller than those of
Gonatoxia maculata
and
Gonatoxia helleri
sp. n. while
Gonatoxia furcata
sp. n. females are generally larger than those of the other three species.
Males are distinguished when comparing the outer genitalic morphology. In
Gonatoxia maculata
the cerci are evenly tapering to their apices, the tips wearing a short and straight serrated ridge (Fig. 3B) while in
Gonatoxia immaculata
the tips of the cerci wear a longer and curved serrated ridge (Fig. 3D, E).
Gonatoxia helleri
sp. n. has similar built cerci as
Gonatoxia maculata
but instead of a serrated ridge (Fig. 3B) a smaller ridge or 1-4 closely clustered teeth are located at the tips. In
Gonatoxia furcata
sp. n. the tips of the male cerci are elongated, scythe-shaped with a very long serrated ridge (Fig. 3G, H, I). Males of all four species have maculae on the tegmina (Fig. 15). In
Gonatoxia maculata
these white patches can be small or large and conspicuous, most specimens had 3-6 of these markings. In the known specimens of
Gonatoxia immaculata
the patches were orange-brown (Fig. 14, 15C). The maculae of
Gonatoxia furcata
sp. n. resemble those of
Gonatoxia immaculata
, being orange-brown.
Gonatoxia helleri
sp. n. usually has small longish white maculae and mostly not more than 2-4 (Fig. 15B, 16A).
Figure 15. Left wings of male
Gonatoxia maculata
(A),
Gonatoxia helleri
sp. n. (B),
Gonatoxia immaculata
(C) and female
Gonatoxia furcata
sp. n. (D). Morphological differences beteen
Gonatoxia maculata
and
Gonatoxia helleri
sp. n. are small. However, usually
Gonatoxia maculata
(A) have more and larger maculae on the tegmina while
Gonatoxia helleri
sp. n. (B) have fewer maculae that are smaller and longish and usually start where Rs branches off (right arrow). Also
Gonatoxia helleri
sp. n. has a white borderd costal margin with veins branching off white and thickened (left arrow).
Figure 16.
Gonatoxia helleri
sp. n., male (A) and female (B) from the Uluguru Mountains.
Description.
Male. Color dark and shiny green, with few ivory patches on tegmina; tergites of abdomen vivid yellow, venter whitish to light green; fore femora dorsally light brown, same colour as tarsi, thus similar to
Gonatoxia immaculata
. Head and antennae. Antennae thin, green, surpassing tegmina by about 1/3. Eyes round, green, with light stripe beginning in eyes, running over the head getting yellow along lateral edges of the pro
notum
. Thorax. Pronotal disc flat with sharp lateral edges, anterior margin v-shaped incurved, posterior margin of disc broadly rounded as described for genus (
Karsch 1889
). Lower margin of pronotal lobes broadly rounded, deeper than long, with sharp edge where wings are inserted. Tegmina broad, posterior end broadly truncate. Stridulation area tri-angle shaped flat on same level as pronotal disc. Stridulatory file evenly tapering in dent size. Alae surpassing tegmina, in this area of same dark green shiny colour; with acute tips. Femora ventrally with spines. Fore tibiae slightly inflated in area of tympana. Abdomen. Last abdominal tergite with straight posterior margin (Fig. 3G). Cerci stout and setose; tips scythe-shaped with long serrated ridge (Fig. 3G, H, I). Subgenital plate with very short lobes, styli slightly inflated (Fig. 3I).
Female. Similar as male in habitus and colour (Fig. 2D) but with broader tegmina. Stridulatory veins as in Fig. 6D. Ovipositor as in Fig. 7C, subgenital plate as in Fig. 9C.
Measurements
(mm).
Females (n=3). Total length of body: 26-27; median length of pronotum: 6.3-6.5; length of hind femur: 25-26.6; length of tegmina: 48-49; width of tegmina: 16; ovipositor: 5.5-6.
Males (n=1): Total length of body: 31.5; median length of pronotum: 6.9; length of hind femur: 25; length of tegmina: 43. Width of tegmina: 13.4.
Etymology.
from Latin: furca = fork because of the forked male cerci.
Habitat.
Lowland wet forest.
Distribution.
At present only known from the Udzungwa Mountains, Tanzania.