New species of Mecopodinae (Orthoptera, Tettigoniidae) from Tanzania
Author
Hemp, Claudia
text
Zootaxa
2020
2020-06-10
4790
1
138
150
journal article
10.11646/zootaxa.4790.1.8
1175-5326
3887942
7F0E923E-7409-4D98-A630-01C61E6DBEF1
Apteroscirtus densissimus
n. sp.
(
Fig. 1–6
)
Holotype
male.
Tanzania
,
Nguru Mountains
, submontane forest,
March 2017
, collected between
6°03´12.1´´S
37°33´38.7´´ E
and
6°04´01.3´´ S
37°34´24.2´´ E
.
Depository
: CCH.
1 male
,
8 females
, same data as holotype and
February and June 2017
,
March 2019
and
March 2020
. Depository: CCH.
Description.
General body shape and colour: stout body, mottled brown to black (
Fig. 1 A, B
). Head and antennae.—Antennae about twice the body length, about
5.5 cm
long. Fastigium verticis with median indentation forming two small „horns“ when seen laterally or from the front (
Fig. 4 A
). Fastigium verticis abruptly forming acute angle to face merging into frons of face without clear separation. Thorax.—Pronotum cylindrical and hardly constricted at first sulcus; disc of pronotum evenly rounded, rugose, of uniform colour. Tegmina not discernible. Legs.—Legs long and slender, base of hind femur stout. Hind femora surpassing apex of body about body length, hind tibiae as long as femora. Tympana of fore tibiae oval and open on both sides. Fore femora on inner side with 2–4 four stout short spines (different number of spines even on the same specimen), outer side unarmed; mid femora unarmed. Hind femora at apical third ventral double row of irregular set spines. Abdomen.—Abdominal tergites medially with smooth wart-like elongate structures, giving males a serrated appearance when seen laterally (
Fig. 1 A, B
). Cerci stout, rounded and short (
Fig. 4 B
). Subgenital plate a typical fork, rather stout and short (
Fig. 4 B, C
); without styli.
FIGURE 1.
Apteroscirtus densissimus
n. sp.
male (
A, B
) and female (
C, D
).
Female. Larger than male. No signs of tegmina, as male apterous. Legs and spination as in male. Pronotum broad with sulci hardly constricting pro-, meso- and metazona and thus almost evenly rounded (
Fig. 5 A
). Dorsum of abdomen as in male, medially with large darker coloured knobs. Ovipositor stout and slightly up-curved at posterior part (
Fig. 1 C, D
). Subgenital plate a broad shield (
Fig. 6 A
).
Measurements, males (mm) (N = 2). Body length 23.2–26. Length of pronotum 6.7–7.0. Length of hind femur 26–27.5.
FIGURE 2.
Male
Apteroscirtus
species; note size differences
A.
A. densissimus
n. sp.
from the Nguru Mountains
B.
A. planidorsatus
from the Uluguru Mountains
C.
A. cristatus
from the West Usambara Mountains.
FIGURE 3.
Head and pronotum and fastigium verticis in more detail of male
Apteroscirtus
species (
A, B
)
Apteroscirtus densissimus
n. sp.
(
C, D
)
A. cristatus
and (
E, F
)
A. planidorsatus
.
FIGURE 4.
Morphological details of male
Apteroscirtus densissimus
n. sp.
A.
Face
B.
Lateral view on male apex
C.
Subgenital plate.
FIGURE 5.
Head and pronotum of female
Apteroscirtus
species
A.
A. densissimus
n. sp.
B.
A. cristatus
C.
A. planidorsatus
.
FIGURE 6.
Subgenital plates of female
Apteroscirtus
species
A.
A. densissimus
n. sp.
B.
A. cristatus
C.
A. planidorsatus
.
Measurements, females (mm) (N = 5). Body length 28.6–33.5. Length of pronotum 7.4–8.0. Length of hind femur 28.3–31.1. Ovipositor length 17.5–18.7.
Diagnosis.
Both males and females of
A. densissimus
n. sp.
differ from the other East African species
A. cristatus
Hemp, 2013
and
A. planidorsatus
Hemp,
2013
in a having an unconstricted broad pronotum that is evenly rounded while the pronotum in both other species is markedly constricted at the first sulcus, especially in
A. planidorsatus
(compare
Fig. 3 A, C, E
and
5
A–C). When seen from above the fastigium verticis is medially incised both in male and female of
A. densissimus
n. sp.
, but has a rugose but more or less straight margin in
A. cristatus
and is smooth and slightly rounded in
A. planidorsatus
(
Fig. 3 B, D, F
). Both males of
A. cristatus
and
A. planidorsatus
have tiny elongated tegminal lobes while in
A. densissimus
n. sp.
no remains of the tegmina were detected. Further
A. densissimus
n. sp.
is larger and stouter than the other two species. The subgenital plates of female
Apteroscirtus
species do not provide good distinguishing characters. Both in
A. densissimus
n. sp.
and
A. cristatus
the female subgenital plate is a broad shield while in
A. planidorsatus
the posterior margin is slightly incised (
Fig. 6
A–C).
Habitat.
A night-active species of the litter and on herbs in submontane to montane forest.
Distribution.
Known at present only from the Nguru Mountains in
Tanzania
.
Etymology.
From Latin -
densissima
, thick, stout since this new species is larger and stouter than the other two Tanzanian
Apteroscirtus
species.