Plangia astylata, Massa, 2021

Massa, Bruno, 2021, Orthoptera Tettigoniidae as indicators of biodiversity hotspots in the Guinean Forests of Central and West Tropical Africa, Zootaxa 4974 (3), pp. 401-458 : 424-425

Plangia astylata n. sp. ( Figs. 31 a-d)

Material examined. Central African Republic, Dzanga-Sangha Special Reserve , Camp 1, 27-28.I.2005 (light), P. Annoyer (♂ holotype) ; Central African Republic, Dzanga-Ndoki National Park , Ndoki, Camp 1, 18.X.2008 (light), P. Annoyer (1♂ paratype) ; Central African Republic, Dzanga-Sangha Special Reserve , Lac 1, 23-24.XI.2010 (light), P. Annoyer (1♂ paratype) ( BMPC) .

Diagnosis. It is a small Plangia , characterized by the absence of styli, cerci long, incurved and very pointed. It was listed as Plangia sp.1 by Massa et al. (2020).

Description. Male. Colour. Yellow-green, abdomen and legs brown; cerci black-tipped. Head and antennae. Fastigium of vertex as wide as scapus, not contiguous with the fastigium of frons. Face smooth. Thorax and legs. Anterior margin of pronotum incurved, posterior margin rounded. Fore coxae armed with a big spine. Fore femora short and compressed, with 4 spines on the inner ventral margin, fore tibiae a little compressed at the base, short, with open tympana, sulcate above, with 2 outer and inner ventral spines + 1 apical spur on each side, and 1 outer dorsal spur. Mid femora with 3 spines on outer ventral margin, mid tibiae with 4 outer and inner ventral spines + 1 apical spur on each side and 1 inner dorsal spur. Hind femora just compressed, wrinkled, with 3 spines on outer ventral margin, hind tibiae with 11 outer and inner dorsal spines and 10 outer and inner ventral spines + 3 apical spurs on each side. Wings. Tegmina 3.2-3.3 times longer than wide, with fore and hind margins more or less parallel, the fore margin only apically rounded. Stridulatory area of the left tegmen well raised, mirror on the right tegmen triangular ( Fig. 31a ), stridulatory file under the left tegmen arched and consisting of ca. 140 teeth more or less regularly spaced, their width decreasing from inner to outer margin ( Fig. 31d ). Abdomen. Cerci regularly decreasing in size, incurved and very pointed ( Fig. 31b ); subgenital plate triangular, styli absent, two small processes similar to the styli present at the apex of the plate ( Fig. 31c ).

Measurements (mm). Male. Body length: 16.9-17.2; pronotum length: 4.3-4.4; length hind femur: 10.2-10.6; tegmina: 24.5-26.4; tegmina width: 8.0-8.1.

Etymology. The name astylata derives from the Latin language and means ‘without styli’ (privative alpha + abjective feminine stylata ).

Affinities. The species of the genus Plangia generally have small or tiny styli (e.g. P. deminuta , P. karschi , P. nebulosa , etc.; but P. variacantans has unusually long styli: Hemp 2017); however, presently species without styli are not known; further, the cerci of the new species are a little similar to those of P. graminea .

Distribution. Presently P. astylata n. sp. is known only from Central African Republic (Dzanga-Ndoki National Park and Dzanga-Sangha Special Reserve).

Figures

FIG. 31. Plangia astylata n. sp.: a) dorsal view of left and right tegmina of the male; b) dorsal view of male cerci; c) ventral view of the male subgenital plate; d) stridulatory file under the male left tegmen.