Ovonotus incisus ( Naskrecki, 1996 )

Naskrecki, Piotr & Guta, Ricardo, 2019, Katydids (Orthoptera: Tettigoniidae) of Gorongosa National Park and Central Mozambique, Zootaxa 4682 (1), pp. 1-119 : 38-41

Ovonotus incisus ( Naskrecki, 1996)

http://lsid.speciesfile.org/urn:lsid: Orthoptera .speciesfile.org:TaxonName:506826

( Figs. 4D , 15 A–E, 17A–K, 49A–C)

Acilaris incisus Naskrecki, 1996: 190 .

Differential diagnosis. Similar to O. abreuae in its general appearance but different in the morphology of the male 10 th tergite, cerci, titillator, and subgenital plate ( Figs. 17 A–I), the female 10 th tergite and subgenital plate ( Fig. 16B ), and bioacoustic characteristics ( Figs. 49 A–C). This species also appears to have only a green color morph.

General. General characteristics as in the description of the genus.

Stridulatory file. Stridulatory file 2.2 mm long, 0.12 mm wide, with 82 teeth ( Fig. 17J ).

Abdomen. Male 10th tergite with two narrow posterior lobes separated by nearly rectangular incision wider than single lobe ( Fig. 17A ); female 10th tergite with deep emargination reaching almost to base of tergite. Cercus short, strongly flattened dorso-ventrally, less than twice as long as wide, bent downwards when seen from side; with basal inner tooth distinctly narrowed towards its apex and with subapical tooth large, blunt, and distinctly separate from apex of cercus ( Figs. 17E, F ). Phallus with well developed, strongly sclerotized, unpaired titillator; with small basal plate, evenly narrow stem, and small apical part as seen from above; apical third of titillator strongly flattened laterally ( Figs. 17G, H ). Subgenital plate with posterior part strongly elongated, diverging into two narrow, incurved lobes and with narrow, spine-like process between them, about as long as third of lobe ( Fig. 17B ); dorsal part of subgenital plate with two small, vertical protrusions at base of apical lobes ( Fig. 17I ); styli minute and stub-like, about as long as wide. Female subgenital plate with posterior emargination wide and shallow, about as wide as posterior lateral lobes ( Fig. 16B ).

Coloration. Coloration light green; head yellow to green, occiput dark, almost black; pronotum green with distinct dark dots in metazona; legs green except for yellow tarsi; ovipositor dark brown, apex almost black. ( Figs. 16 C–E).

Bioacoustics. The call of O. incisus consists of short, 0.5– 0.9 s trains of syllables produced at the rate of 20–30 syllables/sec; (at 22°C); mean syllable duration is 0.01954 (SD=0.00200, n=84), with the frequency peak at 14.6–22.6 kHz ( Figs. 49 A–C). The call, produced by the males only at night, is soft and barely audible to the human ear.

Distribution and natural history. O. incisus is likely restricted in its distribution to the mountainous area on the border of Zimbabwe and Mozambique, in their respective provinces of Manicaland and Manica, from Mt. Selinda and across Chimanimani Mountains. Like its congener, this species is found in humid, shaded habitats, usually on low vegetation, albeit individuals have been seen in large numbers on tree Aidia micrantha (K. Schum.) Bullock ex F. White several meters above the ground. Adults are likely present only during the wet season, beginning in late November. They have been observed feeding on the flowers of a perennial shrub Pseuderanthemum subviscosum (C.B. Clarke) Stapf , although it is likely that they also supplement their diet with insects. Females have been seen depositing eggs inside dried vine stems ( Fig. 4D ). Adults have only been observed at the beginning of the rainy season in December.

Measurements (5 males, 6 females). body: male 22.4–24.4 (23.1.8), female 24–29 (26.91.8); pronotum: male 12.1–13.7 (12.9.7), female 12.3–13.3 (12.9.4); tegmen: male 3.9; hind femur: male 11.7–18.8 (16.62.8), female 18.4–19.7 (19.5); ovipositor: 9.1–11.4 (10.31) mm.

Material examined (17 specimens). Zimbabwe: Manicaland, Mount Selinda (-20.45, 32.7166667), 11.xii.1952, coll. G. v. Son— 1 female (holotype)( SANC) ; 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— 9 females, 6 males, 1 nymph male ( EOWL) .

Figures

FIGURE 4. Egg laying behavior in Mozambican Tettigoniidae: A. Arantia tanzanica, female laying an egg; B. ditto, female covering an egg with masticated bark; C. ditto, an exposed and covered egg; D. Ovonotus incisus; E. Enyaliopsis iaculator; F. Anarytropteris chirinda.

FIGURE 15. Ovonotus abreuae gen. et sp. n., male: A. abdominal apex, dorsal view; B. subgenital plate; C. abdominal apex, ventral view with the subgenital plate removed; D. abdominal apex, lateral view; E. cercus, dorsal view; F. cercus, inner view; G. titillator, lateral view; H. titillator, ventral view; I. subgenital plate, dorsolateral view; J. stridulatory file; K. right tegmen.

FIGURE 16. Ovonotus incisus: A. ovopositor; B. female subgenital plate; C. male, dorsal view; D. female, lateral view; E. male, lateral view.

FIGURE 17. Ovonotus incisus, male: A. abdominal apex, dorsal view; B. subgenital plate; C. abdominal apex, ventral view with the subgenital plate removed; D. abdominal apex, lateral view; E. cercus, dorsal view; F. cercus, inner view; G. titillator, lateral view; H. titillator, ventral view; I. subgenital plate, dorsolateral view; J. stridulatory file; K. right tegmen.

FIGURE 49. Oscillograms and power spectra of Mozambican Tettigoniidae: A–C. Ovonotus incisus; D–F. O. abreuae; G–I. Gorongosa carri; J–L. Enyaliopsis iaculator.