Austrotichus GROSS 1975
Creators: name: Gerry Cassis
name: Loren Vanags
Publisher: name: Zenodo
Year: 2006
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Scutelleridae
Austrotichus

description: Austrotichus GROSS 1975 (Figs 3a, 4, 5, 6)
Austrotichus GROSS 1975: 83 (gen. nov.); MC-DONALD & CASSIS 1984: 538, 545 (key description, genitalia); CASSIS & GROSS 2002: 582 (catalogue)
Type species: Austrotichus rugosus GROSS 1975, by original designation
Diagnosis: Austrotichus is recognised by the following characters: posterior margin of pronotum rectilinear (Fig. 3a); thoracic sterna carinate, not overlapping (Fig. 4c); anterior margin of proepisternum truncate (Fig. 4c); peritreme of metathoracic glands short, arcuate (Fig. 4d); posterior margin of male pygophore medially emarginate (Fig. 4e); CAI absent (Figs 5c, d); CAII(L) without lobal sclerite (Figs 5c, d); CAII(M) with short lobal sclerite (Figs 5c, d); CAIII bifid, medially fused, CAIII(V) with short lobal sclerite (Figs 5c, d); gonocoxae I not divid-ed, medial margins raised; and, spermathecal reservoir membraneous, weakly dilated, elliptoid.
Description: Body elongate-ovoid (Fig. 3a); dorsum and venter strongly convex; wing tip not extending beyond scutellum (Fig. 3a). Head: mostly flattened, posterior aspect of vertex weakly convex (Fig. 4a); jugal margins thickened, subcarinate (Figs 4a, b); bucculae margins subparallel, weakly expanded anteriorly (Fig. 4c). Pronotum: strongly transverse, subtrapezoidal; anterior margin weakly concave (Fig. 3a); anterolateral margins subcarinate; posterior margin rectilinear (Fig. 3a); callosite region weakly demarcated; disc strongly convex, declivent posteriorly (Fig. 3a). Scutellum: broad, strongly depressed beyond anterior 1/2; elliptoid tumescence on anterior margin, marked sublaterally by dark foveae (Fig. 3a); lateral margins convex (Fig. 3a); base of corium and clavus, and connexiva III-VII exposed (Fig. 3a). Thoracic pleura: external efferent system of metathoracic glands well-developed (Fig. 4d); evaporative areas occupying most of metepisternum, extending to mesepimeron (Fig. 4d); ostiole small (Fig. 4d); peritreme short, raised, reniform, not medially sulcate (Fig. 4d). Thoracic sterna: lateral margins sulcate, prosternal and mesosternal keels not overlapping (Fig. 4c); anterior margin of proepisternum truncate, not elevated (Fig. 4c). Male Genitalia: pygophore (Figs 4e, f, 5a) caudally oriented, moderately large, transverse; genital opening dorsal, narrow, suboval, lateral margins setose (Figs 4f, 5a); parameres with columnar stem, moderately hook-shaped crown, flange at base of crown (Fig. 5b); aedeagus (Figs 5c, d): phallotheca short, without processes; ductus seminis proximalis narrow, singular, membraneous, tubelike; ejaculatory apparatus moderately developed; ventral conducting canal with about eight paired convolutions, heavily sclerotized; ejaculatory reservoir small, subelliptical; dorsal conducting canal narrow; ductus seminis distalis and vesica basally incrassate, sinuate, apically truncate; CAI absent; paired CAII greatly enlarged, membraneous, distally bifurcate, lateral branch without sclerotization, medial branch with small, acute lobal sclerite (Figs 5c, d); paired CAIII mostly membraneous, with lateral margins sclerotized, bifurcate, lateral branch membraneous, medial branch with small acute lobal sclerite, medial pair fused along midline (Figs 5c, d). Female Abdominal Venter: posterior margin of SVII weakly bisinuate, weakly thickened medially. Female Terminalia: caudally oriented, bi-planar; paratergites VIII subelliptoid, medially raised; paratergites IX small, narrowly elliptoid, medially rounded; gonocoxae I moderately large, medially depressed, posterior margin concave, medial margins elevated. Spermatheca: short proximal fecundation canal; spermathecal reservoir narrowly dilated, elliptoid, membraneous, without pronounced modifications; pump short, with dorsal and proximal flanges; bulb oval.
Diversity and distribution: Austrotichus is a monotypic genus, which is broadly distributed in temperate Australia, including Victoria, South Australia and Western Australia.
Included species: A. rugosus GROSS 1975 Australia
Remarks: GROSS (1975) described Austrotichus as a monotypic genus, based on external characters alone. MCDONALD & CASSIS (1984) supported its generic status, and described the male and female genitalia. It is a distinctive genus of jewel bug, with a robust body, apomorphic male genitalia and metathoracic glands, and specialized host plant associations. Unlike species of Coleotichus, this genus has the posterior margin of the pronotum rectilinear (Fig. 3a) (also in Solenotichus and Afrotropical Solenosthedium SPINOLA) and the anterior margin of the scutellum is moderately tumose, with sublateral dark foveae (Fig. 3a). The male genitalia of Austrotichus rugosus, with the paired CAIII mostly membraneous (Fig. 5c, d), differs from species of Coleotichus, Solenotichus circuliferus, and extralimital species of Elvisurinae, where the CAIII is sclerotized. In addition, the peritreme is short in Austrotichus (Fig. 4d), much shorter than in Solenotichus (Fig. 9d), still apparent in comparison to Solenosthedium, and much shorter than the consistently elongate peritreme of species of Coleotichus (Fig. 7d).
description: Published as part of Gerry Cassis & Loren Vanags, 2006, Jewel Bugs of Australia (Insecta, Heteroptera, Scutelleridae), pp. 275-398 in Denisia 19 on pages 302-303, DOI: 10.5281/zenodo.12996779