Dioncomena grandis Ragge 1980

Dioncomena grandis Ragge, 1980

http://lsid.speciesfile.org/urn:lsid: Orthoptera.speciesfile.org:TaxonName:12543

(Figs. 29 A–I, 50G–I)

Diagnostic remarks. A slender katydid with a striking, emerald green and black coloration. Easily recognizable by the presence of a bright white spot on the side of the metathorax, black wings (Fig. 29H), and a black markings on the occiput of the head and the dorsal side of the pronotum (Fig. 29I). The posterior portion of the lateral lobe of the pronotum is distinctly inflated over the thoracic auditory spiracle. From other members of the genus Dioncomena this species differs in the shape of the male cercus (Figs. 29D, E) and by the unique structure of the exceptionally wide stridulatory file (file 1.8 mm long, 0.47 mm wide, with 88 widely lamelliform teeth (Fig. 29C).

Bioacoustics. The call of D. grandis is in the form of a series of individual syllables, spaced by at least 30 s of silence syllables; mean syllable duration is 0.042857 s (SD=0.00221, n=14); the peak frequency of the call is 22.8–36.9 kHz (Figs. 50 G–I).

Distribution and natural history. D. grandis is so far known only from a mid-elevation areas within the Chimanimani mountain range in Zimbabwe and Mozambique (Ragge 1980). In Moribane Forest of Chimanimani National Reserve this species is relatively abundant on low herbaceous vegetation along forest edges.

Measurements (3 males, 2 females). body w/wings: male 33–33.1 (33.1), female 32.2–34.5 (33.41.6); body w/o wings: male 15.9–16.7 (16.4.4), female 16.3–22.1 (19.24.1); pronotum: male 3.8–4.3 (4.1.3), female 3.7–4 (3.9.2); tegmen: male 24.7–25.9 (25.2.6), female 24.7–28.1 (26.42.4); hind femur: male 21–21.4 (21.2.2), female 19.7–23.3 (21.52.5); ovipositor: 4.7–5 (4.9.2) mm.

Material examined (8 specimens). Mozambique: Manica, Sussundenga, Moribane Forest, swamp on Rio Tave, elev. 518 m (-19.74072, 33.32133), 2–8.xii.2018, coll. P. Naskrecki & M. Tomás— 3 females, 3 males (EOWL).