Peracca (Robustacca) robustus (Karny, 1923) Ingrisch, 2020

Ingrisch, Sigfrid, 2020, New subgenera and species of Agraeciini (Orthoptera, Tettigoniidae, Conocephalinae) from South Asia found in historical insect collections, Evolutionary Systematics 4 (2), pp. 119-132 : 119

Peracca (Robustacca) robustus (Karny, 1923) comb. nov. Figs 1 , 2

Odontoconus robustus Karny (1923), Ingrisch (1998); Peracca (Odontoconus) robusta Gorochov (2011).

Etymology.

The Latin word robustus does not accept different gender forms.

Specimens studied.

1 female (holotype): Singapore: Bukit Timah (1°20'N, 103°47'E), 23.viii.1911 - depository: BMNH (B.M.1937-197); 1 male, Malaysia, Selangor, Ampang (3°10'N, 101°46'E), 1.iii.1948, coll. H.T. Pagden - depository: BMNH (B.M.1955-354); 1 male, Malaysia, Rompin Mining Co. (Rompin 2°48'N, 103°27'E), Railway Track, 50 km, 31.iii.1961, coll. K.J. Kuncheria - depository: BMH Honolulu.

Remark.

The species was originally described from a single female from Singapore by Karny (1923). Its treatise in Ingrisch (1998) was based on Karny’s description and a single male from SE Pahang in Malaysia. Meanwhile I could study the female holotype and another male from South Malaysia, which are used for a re-description.

Description.

Head with fastigium verticis markedly projecting anteriorly, on top in basal area with a roughly cylindrical process that has the apical area narrowed and rounded (Fig. 2F, I ). Pronotum with rounded fore and truncate hind margin; apical area in male little elevated backwards in male, flat in female. The two central spines at the ventral inner (anterior) margin of the fore femur are markedly enlarged. Prosternum with 2 long spines. Tegmen wide in subbasal area then markedly narrowed to about apical third; tip rounded (Fig. 1E ). Femora with the following number of spines on ventral margins: profemur 6 external, 5-6 internal; mesofemur 6 external, 3 internal; postfemur 12 external, 13-14 internal. Knee lobes of pro- and mesofemur obtuse on external, spinose on internal side; of postfemur uni-spinose on both sides.

Male. Stridulatory file on underside of left tegmen with about 175 teeth; teeth in basal quarter narrow but distinctly spaced, teeth getting wider and more densely packed to about midlength, then becoming very dense and in about apical eighth strongly narrowed (Fig. 1F ). Tenth abdominal tergite strongly setose, apical margin in middle rounded, on both sides substraight but oblique. Cerci with globular base from which two processes arise: the dorsal process is stout but rather short conical with the same sculpturing as at base, pointing mediad and ending into a compressed and subsmooth, triangular, dorso-ventrally compressed, horizontal plate that has the distal angle rounded, the proximal angle acute; the ventral process is elongate, laterally compressed, pointing straight behind, and has a subsmooth surface that carries along dorsal margin numerous spines, at tip it is slightly downcurved and covered with a bunch of spinules (Fig. 1B-D ). Subgenital plate wide in about basal half with rounded lateral margins that are narrowed into a straight, narrow process that is split along midline and upcurved before tip where it terminates into a pair of small acute teeth; without styli (Fig. 1A, B ).

Female. The seventh sternite had been cut for filling the specimen. Subgenital plate with converging and upcurved lateral margins; apical margin in ventral view broadly subtruncate with upcurved margin that is slightly excised in middle (Fig. 2F ). Ovipositor moderately upcurved with area behind mid-length little higher than in subbasal area, then narrowing toward tip; tip of dorsal valves narrow-obtuse, of ventral valves acute (Fig. 2H ).

Measurements (1 male, 1 female). Body w/wings: male 42, female 48; body w/o wings: male 33, female 37; pronotum: male 10.2, female 10.5; tegmen: male 28, female 32; hind femur: male 18, female 21; ovipositor: female 21.5 mm.

Figures

Figure 1. Peracca (Robustacca) robustus (Karny, 1923) comb. nov. male from Ampang (A-C, E-J), male from SE Pahang (D), and female holotype (K): A-C male subgenital plate and cerci in ventral (A), dorsal (B) and lateral view (C); D basal area of male left cercus in medio-dorsal view; E left tegmen, F stridulatory file on underside of left tegmen; G, H stridulatory area of left (G) and right tegmen (H) in dorsal view; I habitus lateral view; J, K ventral view of body and femora of male (J) and female (K).

Figure 2. Peracca (Robustacca) subgen. nov.: A-C P. (R.) nigrifrons sp. nov. female holotype: A face; B fastigium verticis in ventro-anterior view and C in lateral view. - D-I P. (R.) robustus (Karny, 1923) comb. nov. female holotype (D-H) and male from SE Pahang (I) D Face; E fastigium verticis in lateral view; F female subgenital plate; G habitus dorsal view; H habitus lateral view; I fastigium verticis. Abbreviations: lo lateral ocellus, mo medium ocellus.