Agonosoma trilineatum
Creators: name: Gerry Cassis
name: Loren Vanags
Publisher: name: Zenodo
Year: 2006
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Scutelleridae
Agonosoma
Agonosoma trilineatum

description: Agonosoma trilineatum (FABRICIUS 1781) (Figs 16, 17, 18, Table 6)
Cimex trilineatus FABRICIUS 1781: 341 (n. sp.) Cimex sexpunctatus FABRICIUS 1781: 339 (n.sp.); PALEARI 1992: 513 (synonymy) Cimex trivittatus PANZER 1798: 111 (n.sp.); PALEARI 1992: 513 (synonymy) Pachycoris virgatus GERMAR 1839: 102 (n.sp.); PALEARI 1992: 513 (synonymy) Agonosoma quadiguttatum SIGNORET 1851: 330 (n.sp.); WALKER 1867: 59 (list); PALEARI 1992: 513 (synonymy) Agonosoma trivittatum: SIGNORET 1851: 330 (new combination); DALLAS 1851: 42 (list) Agonosoma trilineatum: STÅL 1870: 13 (new combination); SCHOUTEDEN 1904: 68 (synonymy); PALEARI 1992: 505 (redescription) Agonosoma trivittata fabricii KIRKALDY 1909: 278 (unnecessary nom. nov.)
Diagnosis: Agonosoma trilineatum is recognised by the following combination of characters: males chocolate brown, with three longitudinal yellow stripes (Fig. 16a); females dimorphic, as in male, or mostly yellow-brown, with pair of submedial spots on pronotum and scutellum (Fig. 16b).
Colouration. Males monomorphic, dorsum dark chocolate brown with three longitudinal yellow stripes (Fig. 16a); females dimorphic, either as in male, or pale brown with black spots (Fig. 16b). Head: jugal margins black, subjugal regions of frons orange, large fuscous triangular marking from posterior margin of head to near anteclypeus, with medial yellow stripe; underside of head mostly iridescent green, with posterior region orange; AI orange, sometimes tip embrowned, remainder of segment fuscous; LIII mostly dusty stramineous, LIII-LIV fuscous; Pronotum: spotted morph with 6 spots, pairs on anterolateral angles, submedially on anterior margin, and submedially below callosite region. Thoracic pleura: anterior edge of proepisternum yellow, remain-der of pleura fuscous, with green iridescent tinge, intermixed with yellow posterior margin of mesepimeron and peritreme and part of supracoxal lobes. Legs: coxae yellow; femora orange; tibiae fuscous in stripped morph, or mostly orange with anterior surface fuscous; tarsi fuscous. Abdominal Venter: ground colour yellow-orange, with lateral margins dark brown and green iridescence, SV-SVI stridulatory vittae dark brown, SII mostly dark brown, anterior margins of SIII-VII dark brown.
Texture. Dorsum, underside of head and thoracic pleura punctate (Figs 16a, b, 17b).
Vestiture. Body glabrous. Antennae: AI-AII(a) almost glabrous, AII(b)-AIV with dense distribution of short, simple, semi-erect setae; femora with sparse distribution of short setae; ventral surface of tibiae with dense distribution of short, semi-erect setae.
Structure. Antennae: AII(a) smallest segment, AIV longest segment,> AIII, AII(b) little longer than AII(a), AII(b) subequal to AI; AIII and AIV flattened. Labium: reaching abdominal SIII, LII longest segment. Male Genitalia: pygophore with narrow genital opening, laterally setose (Fig. 17d, 18a); parameres with short, broad stem and angulate, elongate crown (Fig. 18b); aedeagus with sclerotized, broad ductus seminis proximalis, bounded by ligamentory tubule (Fig. 18c); ejaculatory apparatus with ventral conducting canal broad, not convoluted (Fig. 18c); ejaculatory reservoir elongate, subreniform (Fig. 18c); ductus seminis distalis broad, scerlotized (Fig. 18c, d); vesica membraneous, denticulate (Fig. 18c, d); CAI and CAIII absent (Fig. 18c); CAII broad, antler-like, distally denticulate (Fig. 18c). Female Terminalia: paratergites VIII small, subtriangular, tapered medially; paratergites IX large, subelliptoid, medial margins rounded; gonocoxae I bipartite, posterior, digitiform branch, anteriorly sub-triangular, moderately-sized. Spermatheca: fecundation canal short; reservoir very weakly dilated, thickened; pump elongate, with proximal and distal flanges present; bulb small, round.
Measurements. Table 6.
Material examined: Venezuela: 5♂♂ 11♀♀, Falcon State, Paraguana Peninsula, 15 December 1999, R Segura & TA Heard, ex Jatropha gossypifolia, quarantine colony (AM).
Distribution: This species was intro-duced to southeast Queensland, and natu-ralised populations are as yet to be recovered (Heard pers. comm.). It is naturally known from Panama, Colombia, Venezuela, Suri-nam, Grenada and Trinidad (PALEARI 1992).
Host plants and biology: Agonosoma tri-lineatum was introduced as a biocontrol agent of Jatropha gossypifolia (see above).
Remarks: PALEARI (1992) redescribed this species, highlighting the colour dimor-phism, external morphology and distribu-tion. It is distinguished from all the native jewel bugs of Australia, on colour and colour patterning alone. It is easily diag-nosed by the enlarged abdominal SVII of both sexes (covering the terminalia) (Fig. 17d, male), the membraneous vesica (Figs 18c, d), and thickened and narrow sper-mathecal reservoir.
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 330-332, DOI: 10.5281/zenodo.12996779