Plangia karschi Chopard, 1954

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 : 428-429

Plangia karschi Chopard, 1954 ( Figs. 32h , 33a–e )

Material examined. Togo, Fazao-Malfakassa NP, Point de vue campsite ( Sudanian Savannah ) (415m) 16- 23.VIII.2018 ( MV Light Trap), M. Aristophanous, M. Geiser, P. Moretto, B. Sanbena (1♂) ; Togo, Fazao-Malfakassa NP, Mare aux crocodiles campsite (Sudanian Savannah /dry Forest ) (505m) 26.VIII-7.IX.2018 ( MV Light Trap), M. Aristophanous, M. Geiser, P. Moretto, B. Sanbena (1♂) ; Côte d’Ivoire, Mt. Tonkoui Peak (1171m) 20- 27.V.2018 ( MV Light Trap), M. Aristophanous, W. Miles, P. Moretto, Y. Outtara (1♂) ; Côte d’Ivoire, Dolla Ranch (tree savannah) (481m) ( MV Light trap) 27.V-5.VI.2018, M. Aristophanous, W. Miles, P. Moretto, Y Outtara (1♀) ( ANHRT) ; Togo, Fazao Hotel 3-4.VIII.2013 ( UV), P. Moretto (1♂, 2♀) ; Côte d’Ivoire, Mt. Tonkoui Peak (1171m) 18-20.VI.2015 ( UV), P. Moretto (1♂) ; same data 12-16.III.2017 ( UV), P. Moretto (1♂, 1♀) ; same data 21.III.2017 ( UV), P. Moretto (2♀) ; same data 7.IV.2018 ( UV), P. Moretto (1♂) ; same data 4.VI.2018 ( UV), P. Moretto (1♀) ; Côte d’Ivoire, Comoe, Zamou (245m) 5-6.VI.2015 ( UV), P. Moretto (2♀) ; same data 2.XI.2016 ( UV), P. Moretto (1♂) ; Côte d’Ivoire, Comoe, Kolomabira (228m) 11.VII.2015 ( UV), P. Moretto (1♀) ; Côte d’Ivoire, Dabakalla, Ouanderama (242m) 22-27.V.2016 ( UV), P. Moretto (1♀) ( BMPC).

Remarks. Chopard (1954) described only the female of this species; the series of males above listed were considered belonging to P. karschi because they were collected together females ascribable to this species. Chopard (1954) wrote that tegmina are 3.5 times longer than wide, but the measurements of the female reported by him indicate 3.8 times longer than wide. Only small differences from the general shape of the female described by Chopard (1954) were noticed. Plangia karschi is one of the complex of species characterized by the black spot on the male stridulatory area of the left tegmen, which very probably replaces P. graminea in West Africa.

Description of the male. Colour. Yellow-green, a black spot on the stridulatory area of the left tegmen; only in some females small scattered brown spots on tegmina ( Figs. 32h , 33 a-b). 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 a little incurved, posterior margin rounded. Fore coxae armed with a big spine. Fore femora short and compressed, with 3 spines on the inner ventral margin, fore tibiae a little compressed at the base, with open tympana, sulcate above, with 2-3 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 3-4 outer and inner ventral spines + 1 apical spur on each side and 1 inner dorsal spur. Hind femora just compressed, externally wrinkled, with 5 spines on outer ventral margin, the outer genicular lobe with a small spine, hind tibiae with 11-12 outer and inner dorsal spines and 10-11 outer and 5-7 inner ventral spines + 3 apical spurs on each side. Wings. Tegmina 3.5-3.8 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 just raised, mirror on the right tegmen triangular ( Fig. 32h ), stridulatory file under the left tegmen arched and consisting of more than 80 teeth regularly spaced, in the middle larger than at both ends ( Fig. 33e ). Abdomen. Cerci stout and in-curved, apically tipped ( Fig. 33c ); subgenital plate triangular, styli small ( Fig. 33d ).

Measurements (mm). Males. Body length: 19.0-24.5; pronotum length: 4.5-5.5; length hind femur: 13.5-16.0; tegmina: 29.0-33.5; tegmina width: 8.0-9.7. Females (in parenthesis after Chopard 1954). Body length: 17.2-24.7 (18.0); pronotum length: 4.2-5.6 (4.6); length hind femur: 10.4-15.5 (16.0); tegmina: 26.0-34.5 (27); tegmina width: 8.2-10.0 (7.1); ovipositor: 4.3-6.5 (4.5).

Affinities. The male of P. karschi differs from P. graminea and P. satiscaerulea by the shape of cerci and the number of teeth in the stridulatory file, from P. astylata n. sp. by the stridulatory file (ca. 140 teeth) and the absence of styli. The male of P. villiersi is unknown, but female tegmina are fairly oval.

Distribution. Chopard (1954) described the female of this species from Mt. Nimba, N’zo and Kéoulenta ( Guinea). Now it is recorded also from Togo and Côte d’Ivoire.

Figures

FIG. 32. Plangia chopardi n. sp.: a) habitus of the female; b) dorsal view of male head, pronotum and tegmina; c) stridulatory file under the male left tegmen; d) dorsal view of male cerci; e) ventral view of the male subgenital plate; f) female ovipositor; g) ventral view of the female subgenital plate; Plangia karschi Chopard, 1954: h) dorsal view of male head, pronotum and tegmina.

FIG. 33. Plangia karschi Chopard, 1954: a) habitus of the male; b) habitus of the female; c) dorsal view of male cerci and styli; d) ventral view of the male subgenital plate; e) stridulatory file under the male left tegmen.