Coleotichus artensis (MONTROUZIER, 1858)

Gerry Cassis & Loren Vanags, 2006, Jewel Bugs of Australia (Insecta, Heteroptera, Scutelleridae), Denisia 19, pp. 275-398 : 310-312

Coleotichus artensis ( MONTROUZIER 1858) ( Figs 3c , 6 )

Scutellera artensis MONTROUZIER 1858: 259 (n.sp.) Coleotichus artensis : STÅL 1873: 4 (new combination); LETHIERRY & SEVERIN 1893: 15 (catalogue); SCHOUTEDEN 1904: 6 (list; separate species); SCHOUTEDEN 1905: 336 (description); SCHOUTEDEN 1907: 107 (Montrouzier type); KIRKALDY 1909: 313 (catalogue); DISTANT 1920: 143 (New Caledonia); MCDONALD & CASSIS 1984: 542, fig. 16 (description; spermatheca); CASSIS & GROSS 2002: 583 (catalogue; synonymy); SMITH 1978: 821 (defensive secretion) Coleotichus marginatus SIGNORET 1861: 59 (n.sp.); STÅL 1873: 4 (synonymy) Coleotichus sordidus WALKER 1867: 1 (n.sp.); DISTANT 1899: 50 (as junior synonym of Coleotichus fuscus ); CHINA 1930: 91 (Samoa); SMITH 1978: 821 (defense); MCDONALD & CASSIS 1984: 542 (synonymy) Coleotichus discrepans WALKER 1867: 2 (n.sp.); MCDONALD 1961: 179, figs 24-28 (male genitalia); MCDONALD 1963a: 179, figs 24-28 (male genitalia); MCDONALD 1963b: 223, figs 15-16 (female genitalia); MCDONALD & CASSIS 1984: 542 (synonymy) Coleotichus nigrovarius WALKER 1867: 2 (n.sp.); MCDONALD & CASSIS 1984: 542 (synonymy) Coleotichus testaceus WALKER 1867: 2 (n.sp.); STÅL 1873: 4 (synonymy)

Diagnosis: Coleotichus artensis is recognised by the following combination of characters: AIV longest antennal segment; callosite region of pronotum with four prominent black spots; labium reaching apex of metasternum; female abdominal SVII narrow caudally, ventral margin deeply concave; males without abdominal sternal glands; posterior margin of male pygophore excavate; CAII symmetrical, tripartite; CAII fused post-thecal margin; vesica elongate; and, proximal sclerotization of spermathecal fecundation canal.

Description: Body elongate-ovoid ( Fig. 3c ); moderately sized, males 12.8-14.7 mm, females 12.6-14.7 mm.

Colouration. Body stramineous-brown to dark-brown, sometimes with mottled appearance, punctures dark-brown to black, sometimes with green iridescence ( Fig. 3c ). Head: stramineous-brown, sometimes darker with clypeal margins fuscous, reaching posterior margin of vertex, posterior margin of head rarely transversely fuscous; anterior margin of pronotum sometimes dark brown to fuscous; pronotal calli with prominent dark brown to fuscous spots; anterolateral angles of scutellum with black spot; scutellum often mottled, sometimes with medial darker brown oblique fasciae; thoracic pleura and abdominal sterna yellow-brown to dark-brown; deep punctures of proepisternal keel sometimes with green iridescence; abdominal spiracular-trichobothrial region contrastingly dark-brown; appendages concolorous, pale to dark brown.

Texture. Dorsum with dense distribution of deep punctures, less so on head, more so on scutellum and pronotal disc, irregularly distributed; thoracic pleura with deep punctures submarginally on propleuron and mesopleuron.

Vestiture. Dorsum near glabrous. Antennae: AI-AII(a) almost glabrous, AII(b)- AIV densely pilose, with short simple semierect setae. Legs: ventral margins of tibiae densely pilose.Underside of body with scattered short simple setae; lateral margins of abdominal sterna more densely pilose.

Structure. Antennae: AI(a) little longer than AII(b), AIV longest segment. Labium: reaching apex of metasternum. Thoracic Pleura: external efferent system of metathoracic glands extensive, peritreme elongate, strongly recurved towards head. Abdominal Venter: SIII with medial anteriorly projecting processes; posterior angles of SIV-SVII acute, particularly SVII; female abdominal SVII narrow caudally, posterior margin deeply concave; males without abdominal sternal glands. Male Genitalia: posterior margin of male pygophore excavate, with medial setose patches; parameres with flange at base of crown; phallotheca with pair of subdistal thorn-like processes; ejaculatory reservoir heavily sclerotized; ductus seminis distalis basally incrassate; CAI absent; CAII symmetrical, tripartite mostly membraneous, CAII(L) with large, elongate sickle-shaped lobal sclerite, CAII(M) with small, bifid lobal sclerite, paired ventral CAII process with laterally oriented bill-shaped lobal sclerites; CAIII strongly sclerotised, medially fused, with apices arcuate, laterally directed, vesica elongate, extending beyond conjunctival appendages. Female Terminalia: paratergites VIII moderately sized, subtriangular, posteri-or margin arcuate, medially separated; paratergites moderately sized, subtriangular, medial margins truncate; gonocoxae I subtriangular. Spermatheca: proximal fecundation canal short, base sclerotized; bulb oval, heavily sclerotized.

Measurements. MCDONALD & CASSIS 1984: Table 1 .

Type material examined: Coleotichus artensis MONTROUZIER : Holotype, ♀, ‘ B.M. Hem. 365 ’, ‘ New Caled’, ‘59-63’ ; Coleotichus discrepans WALKER : Holotype, ♀, ‘ B.M. Hem Type No. 366 ’, ‘ Moreton Bay’ ( BMNH) ; Coleotichus nigrovarius WALKER : Holotype, ♀, ‘ B.M. Hem Type No. 367 ’, ‘ Fiji Isles, Ovalau’ , ‘56-69’, ‘585’ ( BMNH) ; Coleotichus sordidus WALKER : Holotype, 1♀, ‘ B.M. Hem Type No. 368 ’, ‘ I of Pines’ ( BMNH) ; Coleotichus testaceus WALKER : Lectotype, ♀, ‘ New Caled’, ‘B.M. Hem. Type No. 365’ , ‘ Coleotichus testaceus WALKER’ s catal.’, ‘59-63’ (BMNH; here designated); Paralectotype, ♀, ‘ Moreton Bay’ , ‘artensis Montr. ’ ( BMNH ; here designated). WALKER (1867) described C. tes-taceus from two specimens; the original description listing them as: ‘a. New Caledonia. ‘From Mr Macgillvray’s collection’ and ‘b. Moreton Bay . From Mr Diggles’ collection’. The lectotype and paralectotype specimens designated here, bear labels with these localities respectively.

Other material examined: Queensland: 1♀, Kuranda , 5 December 1988, R Bejsak ( AM) ; 1♀, Cairns, Crystal Cascades , 1 February 1989, J & M Bugeja ( AM) ; 1♀, Kuranda Range, State Forest , 10 January 1967, DK McAlpine & G Holloway ( AM) ; 1♀, Bluewater Range , 16-v-1990, T Woodger ( AM) ; 1♂, 14 km ENE Heathlands , 11.41S 142.42E, 21 October 1993, P Zborowski & DCF Rentz, at light, rainforest ( ANIC) ; 2♀♀, Shiptons Flat, 15.47S 145.14E, 17 October 1980, T Weir ( ANIC) ; 1♀, 9 km SSW Kuranda, 16.54S 145.37E, 25-26 November 1992, A Calder & P Zborowski, at light ( ANIC) ; 1♀, 2 km N Kuranda , 16.48S 145.38E, 20 November 1981 ( ANIC) ; 1♀, FP Dodd, 1907-54, ‘det. as Coleotichus discrepans ’ ( BMNH) ; 1♀, Redlynch, 21-30-viii-1938, RG Wind, ‘det. as Coleotichus discrepans ’ ( BMNH) ; New South Wales: 4♂♂ 1♀, 3 to 5 km NE of Harrington , G Williams, January 1989 & 1991, ex Alphitonia excelsa , littoral rainforest ( AM) ; FIJI: 1♂, Cuvie , ‘1920-82’, ii-1918, R Veitch, ‘det. as Coleotichus nigrovarius ’ ( BMNH) ; TONGA: ‘Distant Coll. 1911-383’, ‘det. as Coleotichus nigrovarius WALK. ’ ( BMNH) ; VANUATU: 6♂♂ 6♀♀, Aneityum, 3 mi. NE Anelgauhat, Red Crest , 200 ft, iii-1955, LE Cheesman, B.M. 1955217 ( BMNH).

Distribution: Coleotichus artensis is broadly distributed in the tropical regions of the Australian zoogeographic region; known from Australia, Indonesia, Papua New Guinea, Fiji, New Caledonia, Samoa and Vanuatu ( CASSIS & GROSS 2002). Within Australia, it was known previously from the tropical parts of the Northern Territory and Queensland. In this work, we greatly extend its range to the south, with new collections from the mid-north coast of New South Wales (near Harrington) ( Fig. 6 ). There is also a significant distributional gap between the populations of the wet tropics and subtropical regions of Queensland.

Host plants and biology: Coleotichus artensis was collected from the flowers of the littoral rainforest tree, Alphitonia excelsa ( Rhamnaceae ), during two separate collection events. This represents the first record-ed plant association for this jewel bug species, but doubt remains as to whether this is its food plant or breeding host.

Remarks: MCDONALD & CASSIS (1984) redescribed C. artensis and gave a detailed synonymy. It exhibits variability in colour, ranging from matt light brown to polished dark brown, otherwise it is homogeneous, particularly in the male genitalia. We recently re-examined all the types, aside from C. marginatus , and found that a wider examination of extralimital specimens of this species is required to confirm the identity of this species and the above-mentioned synonymy. As the types are all females, doubts of the validity of the given species synonymy prevail, as the male genitalia remain the chief criterion for distinguishing species. The holotype of C. sordidus , which was described from a New Caledonian specimen (Isle of Pines), is possibly deserving of species resurrection, as it is pale brown without patterned spotting, the pronotal humeral angles are more rounded, and the posterolateral angles of the abdominal venter are not pronounced, as in the other types. However, we have refrained from removing the latter from synonymy pending a generic revision of Coleotichus , and found that its pale colouration is consistent with individuals found in Australian populations that we observed.

Coleotichus artensis most resembles C. costatus in colour and size, although the mean lengths of both sexes of C. artensis are smaller and the maximal width of males is a little larger. The male genitalia of C. artensis are discrete with the CAII tripartite; a character state which does not occur in all other species of Coleotichus investigated. Like oth-er species of Coleotichus , the male genitalia of C. artensis exhibit little intraspecific variation. Its closest relationships may lie with extralimital species such as C. biroi , which it resembles on the basis of external characters and size. The female genitalia of C. artensis and C. costatus are alike, with the proximal sclerotization of the fecundation canal, a feature not found in C. excellens .

Figures

Fig. 3: Habitus of Australian Elvisurinae species (a) Austrotichus rugosus, Oi (b) Solenotichus circuliferus, Oi (c) Coleotichus artensis, Oi (d) Coleotichus costatus, Oi (e) Coleotichus excellens, Oi. Scale bars: 1 mm.

Fig. 6: Distribution of Australian Elvisurinae species.