Gymnogryllus bilongi Um Nyobe & Kekeunou, 2023

Nyobe, Philene Corinne Aude Um, Ngoute, Charly Oumarou, Richard, Nzoko Fiemapong Armand, Robillard, Tony, Ma, Libin & Kekeunou, Sevilor, 2023, Description of one new species of the genus Gymnogryllus (Orthoptera, Gryllidae, Gryllinae) from Cameroon with a key for African species, Zootaxa 5369 (4), pp. 591-596 : 592-594

Gymnogryllus bilongi Um Nyobe & Kekeunou sp. nov.

Materials examined. Holotype: male, CAMEROON, Center Region , Zamakoe (3°33’816”N, 11°31’913”E) secondary forest, 19/x/2014; quadrat; Coll. Um Nyobe, Oumarou & Nzoko; deposited in the Zoology Laboratory, of University of Yaoundé 1, Cameroon ( ZLUYC).

Paratypes: 1 female, CAMEROON, Center Region, Ongot (3°85’786” N, 11°38’333” E), secondary forest, 26/x/2014, pitfall trap; Coll. Um Nyobe, Oumarou & Nzoko; deposited in the Zoology Laboratory, of University of Yaoundé 1, Cameroon ( ZLUYC) ; 2 females, CAMEROON, South Region; Engout’Adjap (2°42’N, 11°03’E), crops field (11/x/2014, 08/xi/2014); quadrat; Coll. Um Nyobe, Oumarou & Nzoko; deposited in the Zoology Laboratory, of University of Yaoundé 1, Cameroon ( ZLUYC) .

Etymology. Gymnogryllus bilongi Um Nyobe & Kekeunou sp. nov. is a commemorative name, to honor Pr. Charles Felix Bilong Bilong for his great contribution to taxonomic research in animal biology.

Diagnosis. The anterior edge of the pronotum with a V-shaped groove; the posterior edge straight; a triangularshaped mirror that having no dividing cells and its apical field very short; the epiphallic lobes pointed and curved internally, separated by a large U-shaped space; the ectoparameres long, wide and rounded at their distal end.

Differential diagnosis

Gymnogryllus bilongi Um Nyobe & Kekeunou sp. nov. is most similar to Gymnogryllus ebneri ( Chopard, 1927) in the structure of forewings but differs by the genitalia. G. ebneri has two epiphallic lobes not pointed and curved internally, separated by a large V-shaped space and the ectoparameres are long and slender. G. bilongi is also most similar to one species also found in Cameroon, Gymnogryllus brevipennis Chopard, 1934 from which it differs in male genitalia and forewings. For G. brevipennis , the epiphallic lobes are not curved internally and it has four veins in the harp.

Description

( Figs. 1A–I ; 2A–I ; Table 1 )

Male. The specimen studied is medium in size; his body is covered with short and fine pubescence. Head: dark brown; occiput with weakly marked brown stripes ( Figure 1A ); cheeks completely black ( Figure 1 B ); fronto-clypeal suture slightly arched; face and labrum dark brown; head and pronotum equal in width ( Figure 1 C ). Pronotum: anterior edge with a V-shaped groove; posterior edge straight; front wider than rear; disc dark brown on two-thirds of its front part and dark brown with brownish spots on the third of its lower part ( Figure 1 A ); lateral lobes completely dark brown; posterior and anterior margins of pronotum with bristles. ( Figure 1 B ). Wings: forewings reaching the middle of the abdomen with two oblique veins in the harp; triangular mirror devoid of division cells with a very short apical field ( Figure 1 D ); hindwings absent. Abdomen: dorsum variegated brown and ivory-colored, with a median row of dark marks, and on either side of this row a pale band; venter light brown; subgenital plate dark brown with two spots black near the base; cerci dark brown, but very pale at the base. Legs: fore- and middle tibiae lightly ciliated with long hairs, orange-brown turning brown in basal and distal extremities, with 3 and 4 apical spurs respectively; tympanal openings on both sides of foretibiae, the outer one twice as large as the inner ( Figure 1 E, F ); hind legs orange-brown ( Figure 1 G ); hind femora with faint brown stripes on the outer face; hind tibia with 6 inner and 7 outer subapical spurs ( Figure 1 H ). Male genitalia: epiphallus with two pointed lobes curved internally, separated by a large U-shaped space; ectoparameres long, wide and rounded at their distal end; virga very long and thin ( Figure 1 I ).

Females. They look morphologically like males although their anterior wings are micropterous with rounded ends ( Figure 2 ). In addition, they appear larger and have a different number of subapical spurs: 4 inner and 5 outer ( Table 1 ).

Figures

FIGURE 1. Gymnogryllus bilongi sp. nov. Holotype (male). A. Head and pronotum in dorsal view; B. Head and pronotum in lateral view; C. Head in ventral view; D. Forewing; E. External face of the anterior tibia with an oval and elongated tympanum; F. Internal face of the anterior tibia with a short and round tympanum; G. External face of orange-brown femora; H. Posterior brown tibia; I. Genitalia. Scale bars: A, 8 mm; B, G, H, 4 mm; C, 6 mm; D, 9 mm; E, F, 5 mm; I, 500 µm.

FIGURE 2. Gymnogryllus bilongi sp. nov. Paratype (female). A. Head and pronotum in dorsal view; B. Head and pronotum in lateral view; C. Head in ventral view; D. Forewing; E. Internal face of the anterior tibia with a short and round tympanum; F. External face of the anterior tibia with an oval and elongated tympanum; G. External face of orange-brown femora; H. Posterior brown tibia; I. Abdomen in dorsal view; J. Abdomen in ventral view; K. Ovipositor. Scale bars:A, 9 mm; B, C, 6 mm; D, 8 mm; E, F, K, 5 mm; G, H, 4 mm; I, J, 7 mm.