Cantao AMYOT & SERVILLE 1843
Creators: name: Gerry Cassis
name: Loren Vanags
Publisher: name: Zenodo
Year: 2006
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Scutelleridae
Cantao

description: Cantao AMYOT & SERVILLE 1843 (Figs 1b, 21e, 27, 28a, 29, 30)
Cantao AMYOT & SERVILLE 1843: 29 (gen.n.); DALLAS 1851: 3, 17 (key, list); STÅL 1865: 33 (key); MAYR 1866: 14 (description); STÅL 1873: 10 (list); LETHIERRY & SEVERIN 1893: 18 (catalogue); DISTANT 1902: 42 (description); SCHOUTEDEN 1904: 18 (description); KIRKALDY 1909: 307 (catalogue); MCDONALD & CASSIS 1984: 550, 552 (key, description); CASSIS & GROSS 2002: 591 (catalogue) Cantao (IostetHus) STÅL 1873: 10 (gen.n.); KIRKALDY 1909: 307 (catalogue)
Type species: Cantao: Cimex ocellatus THUNBERG 1789, subsequent designation, KIRKALDY 1909: 307; Cantao (IostetHus): Calidea parentum WHITE 1839: 85, subsequent designation, KIRKALDY 1909: 307
Diagnosis: Cantao is recognised by the following characters: elongate-ovoid (Figs 1b, 28a); large size; bicoloured, orange or red with fuscous to dark blue markings (Figs 1b, 28a), sometimes with green iridescence ventrally; body smooth, punctulate to rugo-punctulate (Figs 1b, 28a); hemelytra extending beyond tip of abdomen; lateral margins of jugae almost straight (Fig. 29a), carinate in profile (Fig. 29b); anterolateral margins of pronotum carinate; anterolateral angles of scutellum foveate (Figs 1b, 28a); apex of scutellum truncate (Fig. 28a); peritreme greatly enlarged, subtriangular, raised, sulcate at base (Fig. 29d); abdominal SVIII visible (Fig. 29e); male pygophore large, ventrally oriented (Fig. 29e); ejaculatory apparatus with convoluted ventral conducting canals (Figs 30c, d); CAII undivid-ed, with blunt lobal sclerite (Figs 30c, d); spermathecal reservoir large, oval; spermathecal pump with proximal and distal flanges.
Description: Body elongate-ovoid, hemelytra extending beyond truncate tip of scutellum (Figs 1b, 28a); dorsum ground colour yellow, orange or red-brown with patterned fuscous to black markings (Figs 1b, 28a), venter with green-fuscous iridescent patterned markings; body smooth, punctulate to rugo-punctulate; ventral surface densely setate with rows of setae on anterior margin of proepisternum and evaporative areas posteriad to peritreme. Head: transverse, convex in dorsal view; jugal margins carinate; jugae rugulose; bucculae narrow, sometimes margins weakly excavate. Antennae: AI and AII(a) short, AII(b)-AIV subequal in length. Labium: reaching between apices of metacoxae and basal abdominal sterna. Pronotum: broadly trapezoidal, wider than long (Figs 1b, 28a), evenly convex in profile, without a transverse furrow, posteriad to callosite region; anterior margin deeply excavate (Figs 1b, 28a), sometimes weakly depressed; anterolateral margins strongly carinate, weakly to strong-ly concave (Figs 1b, 28a); posterior margin weakly excavate (Fig. 28a); humeral angles rounded (Figs 1b, 28a) to prominently spinose; posterior angles, with posteriorly projecting thorn-like process. Scutellum: elongate (Fig. 28a), strongly convex in profile; anterolateral region deeply foveate (Figs 1b, 28a), forewings minimally exposed basally; truncate apically, wings visible (Figs 1b, 28a). Thoracic sterna: without carination (Fig. 29c). Thoracic pleura: anterior margin of proepisternum thickened (Fig. 29c). Thoracic Pleura: ostiole small, with greatly enlarged subtriangular peritreme, with shallow basal sulcation (Fig. 29d); evaporative areas restricted to anterior and posterior margins of peritreme, not extending laterally beyond peritreme (Fig. 29d); mesepimeron without evaporative areas. Male Pregenital Abdomen: moderately convex, broad; abdominal trichobothria in recessed area; SVIII visible, caudally extending well beyond base of pygophore (Fig. 29e). Male Genitalia: pygophore large, barrel-shaped, ventral surface sometimes with excavation, ventral margin sometimes with a U- or V-shaped projection medially (Figs 29e, f); genital opening broad (Fig. 30a), suboval, sometimes with ventral bifid pygophoral process; parameres hook-shaped, with apices rounded (Fig. 30b) to acute; aedeagus with moderately sclerotized phallotheca, subconical, without processes (Figs 30a, b); CAII membraneous, with blunt lobal sclerite, basally with area of sclerotisation (Figs 30c, d); CAIII U-shaped, heavily sclerotized (Fig. 30d); ductus seminis proximalis narrow, within a phallothecal extension (Fig. 30c); ejaculatory apparatus with highly convoluted ventral conducting canal, with up to 12 convolutions (Figs 30c, d); ejaculatory reservoir sclerotised (Fig. 30c); ductus seminis dorsalis and vesica with subapical tumescence (Fig. 30c). Female Terminalia: caudally oriented, sometimes recessed; paratergites VIII large, subtriangular; paratergites IX small to absent. Spermatheca: base of spermatheca strongly sclerotized; fecundation canal elongate, moderately sclerotized; spermathecal reservoir oval, robust; sclerotized proximal and distal flanges present; and, usually, with heavily sclerotized oval bulb.
Diversity and distribution: Cantao has an Indo-Pacific distribution (sensu SCHUH & STONEDAHL 1986). The Australian species C. parentum is found through coastal Queensland, as far south as the Northern Rivers district of New South Wales. There is some doubt as to the native distribution and identity of C. africanus. HORVÁTH’S (1892) original description gives the Congo as the type locality. SCHOUTEDEN (1904) suggested that the species could be either from the Congo or Queensland. MCDONALD (1988) queried if C. africanus is a synonym of C. ocellatus, based on identified material of the latter from Zaire. Cantao ocellatus is the most broadly distributed species in the genus, and is found from the Afrotropical region to Papua New Guinea, as well as many countries in the Oriental region, and extending westward as far as Pakistan. The other three species of Cantao exhibit more restricted distributions in the eastern Oriental region and the Australian region.
Included species: C. africanus HORVÁTH 1892 Afrotropical region C. ocellatus (THUNBERG 1784) Afrotropical (Zaire), Oriental (broadly) and Palearctic (Regions) regions, Papua New Guinea C. variabilis (MONTROUZIER 1855) Indonesia, Philippines, Papua New Guinea C. parentum (WHITE 1839) Australia C. purpuratus (WESTWOOD 1837) Indonesia (Banda, Timor)
Remarks: SCHOUTEDEN (1904) divided Cantao into two subgenera; Cantao (Cantao) and Cantao (IostetHus), based on the presence or absence of punctures, respectively. MCDONALD (1988) synonymized these two subgenera, implicitly dismissing the importance of punctation. We endorse this view, particularly as the supposedly smooth body of C. parentum and C. purpuratus has minor punctulation. The male and female genitalia of all Cantao species are alike. In males, the aedeagus has two pairs of conjunctival appendages (CAII and CAIII), an ejaculatory apparatus with a ventral convoluted conducting canal; typical of scutellerines. In addition, the male abdominal SVIII is visible, overlapping the basal margin of the Py-gophore. The females have terminally oriented external genitalia, and the spermathecal reservoir is oval and large. In Cantao there is surprising variation in the development of paratergites IX, which can be present (parentum) or reduced/absent (africanus, ocellatus and variabilis).
The sister-genus of Cantao is not apparent, as it shares a number of features with numerous Old World genera. MCDONALD (1988) suggested that Cantao is closely related to CallipHara, Callidea LAPORTE and CHrysocoris, but gave no morphological basis for such an hypothesis. Cantao, like other scutellerine genera such as CHrysopHara, Lampromicra and ScutipHora, has the forewings extending beyond the tip of the scutellum and the female external genitalia terminal in orientation. However, the external efferent system of the metathoracic glands of Cantao is distinctive, with the evaporative areas reduced and the peritreme greatly enlarged. This is unlike that found in genera such as CallipHara, CHrysocoris, Lampromicra and ScutipHora, and similar to the condition found in Calliscyta.
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 350-354, DOI: 10.5281/zenodo.12996779