Bioacoustics of Arantia (Euarantia) congensis

Measurements . Males. Body length: 32.2±2.7; pronotum length: 6.7±0.2; pronotum height: 6.3±0.2; hind femur: 32.3±0.9; hind tibiae: 37.3±0.7; tegmina: 47.1±1.3; tegmina width: 16–19; tegmina width/pronotum length: 2.4–2.7 (present data). Female. Body length: 31; pronotum length: 7.2; tegmina: 51.5; tegmina width: 18; ovipositor: 4.4 ( Griffini 1908 ). Characters . A . congensis is a species of medium size (body length ♂ 29.5–36.1 mm , ♀ 31 mm ) ( Fig. 29 ). Griffini (1908) described it from the Democratic Republic Congo as subspecies of A . melanota . According to Griffini (1908) it is similar to A . melanota but is characterized by longer fore femora ( 11 mm in A . congensis vs. 10.7 mm in A . melanota ), broader tegmina, and different cerci. It has a narrow pronotum, and clearly longer and more slender legs than any other species of the genus Arantia . In addition, it has broad-based spines ventrally on the hind femora. The anterior margin of the pronotum is slightly concave, the posterior margin rounded. The lower margins of the pronotal lobes lack the concavity usually present in other species of the genus. Tegmina are 2.8–3.3 times longer than broad, about a dozen of hexagons formed by the veinlets centrally on the tegmen. The stridulatory file of the left tegmen is slightly curved, with 95–100 teeth ( Fig. 61 ). A small spine is present at the posterior end of tergites 2th–8th. Fore coxae unarmed. Fore femora with 3–5 inner ventral spines, fore tibiae with 7– 8 inner and outer ventral spines, and 4–5 dorsally. Mid femora unarmed, mid tibiae dorsally and ventrally with 11– 12 outer and inner ventral spines and 6–7 outer and inner dorsal spines. Hind femora with 6–8 outer and 4–5 inner ventral spines, the last 4 spines broad-based and black-tipped. Hind tibiae curved, with 12–14 outer and 9–11 inner ventral spines. Tibiae and femora are long and slender. Very characteristic are the male cerci; the bases are spoonlike expanded at the tips, with a subapical process ( Fig. 92 ). The subgenital plate is triangular, tricarinate, the apex is concave with two tips, similar to styli, that are obliterated. The female has been re-described by Heller et al . (2014) . It is characterized by unusually large and broadbased spines (especially the last two) on both edges ventrally on the hind femur. The ovipositor has two lateral protuberances. Colour . Probably predominantly green in life, preserved insects with yellowish to tawny areas. Antennal segments reddish with small black rings. Tympana dark or only dark at their apex. Tegmina oval, green with a dark stripe at the base and some yellow spots on the vertical veinlets ( Fig. 29 ).