Arachnoscelis Karny 1911

Montealegre-Z, Fernando, Cadena-Castañeda, Oscar J. & Chivers, Benedict, 2013, The spider-like katydid Arachnoscelis (Orthoptera: Tettigoniidae: Listroscelidinae): anatomical study of the genus, Zootaxa 3666 (4), pp. 591-600 : 592

Arachnoscelis Karny 1911

Karny. 1911. Verh. der Zoologisch-Botanischen Gesellsch. Wien 61: 334–347 Karny. 1912. Genera Insectorum 131:3

Bruner, L. 1915. Annals of the Carnegie Museum 9 (3–4):363 Randell. 1964. Canadian Ent. 96:1608

Gorochov. 1995 [1994]. Zoosystematica Rossica 3(2):202 Otte, D. 1997. Orthoptera Species File 7: 80

Nickle. 2002. J. Orth. Res. 11 (2):127

Gorochov. 2007. Zoosystematica Rossica 16 (2): 210 Gorochov. 2012. Trudy Zoologicheskogo Instituta 316(4):287

Redescription of the genus. Head elongated in males. Male mandibles well developed, mandible elongated. Head, and mandibles of the female of normal appearance ( Fig. 2 ). Males and females with notoriously large maxillary palps. Legs: Fore tibia distally decurved with 5 pairs of movable spines on the ventral surface ( Fig. 3 ); tympanal area on the proximal part of fore tibia inflated, with a pair of tympanal openings that are antero-distally elongated, spacious, and asymmetrical; the anterior opening is narrower than the posterior one. Distal margin of both tympanal openings rounded, proximally this margin is acute. Wings: Male brachypterous, tegmina reduced to the size of the stridulatory area ( Figs. 1 A, and 4A–E). Massive vein (formed by the merging of several veins), curves towards the anal area, ends blunt and weakly connects to CuPaa2 through the narrow handle vein (h in Fig. 4 E) and vein CuPaa2+CuPaß. The wing shows a large soft area between M+CuA end and CuPaa2 ( Fig. 4 E). Tympanal slits elongated, relatively broad and asymmetrical ( Fig. 5 A). Scraper area subquadrate, as large as the mirror area. Genitalia: Male subgenital plate broad with a broad v-shape notch, with two distinct styli. Female subgenital plate elongated, upturned, with distal bifurcation ( Fig. 5 B).

Figures

FIGURE 1. Arachnoscelis arachnoides habitus; A. Male; B. Female.

FIGURE 2. Distinguishing structures of the head of Arachnoscelis arachnoides: A. rostrum of a male and a female; B. Male right mandible seen from internal and dorsal view; C. Isolated right mandible of the female in dorsal view. B and C illustrate mandible sexual dimorphism in the head structure; note the conspicuous enlargement of the mandible body in males.

FIGURE 3. Arachnoscelis arachnoides, female habitus.

FIGURE 4. The stridulatory file of Arachnoscelis arachnoides: A. The entire left tegmen in ventral view showing the stridulatory file and mirror; B. A close up view of the file. C. Average inter-tooth spacing measured from two males. Error bars indicate one standard error; D. Male tegmina in resting position; E. Right tegmen illustrating venation pattern. Venation nomenclature follows Bethoux (2012).

FIGURE 5. Distinguishing structures between males and females: A. Proximal part of the left tibia showing tympanal slits; B. Subgenital plates of males and females in ventral view. The male diagram also depicts cerci and styli; C. Lateral view of the male terminalia showing cerci, subgenital plate and titillators.