Coleotichus costatus ( FABRICIUS 1787 )

Gerry Cassis & Loren Vanags, 2006, Jewel Bugs of Australia (Insecta, Heteroptera, Scutelleridae), Denisia 19, pp. 275-398 : 312-314

Coleotichus costatus ( FABRICIUS 1787) ( Figs 3d , 6 , 7 , 8 )

Cimex costatus FABRICIUS 1787: 282 (n.sp.); DONOVAN 1805: pl. 3 fig. 5 (habitus); GERMAR 1839: 74 (list)

Tetyra costatus : FABRICIUS 1803: 135 (new combination) Coleotichus costatus : WHITE 1842: 88 (new combination); WALKER 1867: 1 (list); WALKER 1868: 505 (list); STÅL 1873: 4 (list); LETHIERRY & SEVERIN 1893: 15 (catalogue); SCHOUTEDEN 1904: 6 (list); Kirkaldy 1909: 313 (catalogue; as junior synonym of Coleotichus unicolor ) DISTANT 1920: 143 (New Caledonia); KUMAR 1965: 46 (male genitalia); GROSS 1975: 81 (description); VAN DEN BERG 1980: 223-225 (biology; host plant); MCDONALD & CASSIS 1984: 9 (redescription; synonymy; male genitalia: Figs 3-7 , 9 ; female genitalia: Figs 7 & 8 ); CASSIS & GROSS 2002: 584 (catalogue)

Eurygaster costatus : VOLLENHOVEN 1863: 39 (new combination)

Coleotichus unicolor DALLAS 1851: 5 (n.sp.); SCHOUTEDEN 1904: 6 (synonymy)

Coleotichus pallidus VOLLENHOVEN 1863: 4 (n.sp.); SCHOUTEDEN 1904: 6 (synonymy)

Diagnosis: Coleotichus costatus is recognised by the following combination of characters: AIII and AIV subequal, longest antennal segments; callosite region of pronotum with pair of small submedial black spots ( Fig. 3d ); labium reaching anterior margin of metacoxae; female abdominal SVII broad caudally, ventral margin shallowly concave; males with abdominal sternal glands on SIV-VI ( Figs 2 a-c); posterior margin of pygophore arcuate; CAII asymmetrical ( Figs 8c, d ); CAII fused post-thecal margin ( Figs 8c, d ); vesica elongate ( Figs 8c, d ); and, basal sclerotisation of spermathecal fecundation canal.

Description: Body elongate-ovoid ( Fig. 3d ); moderately large, males 12.6-15.5 mm, females 13.4-17.2 mm.

Colouration. Body yellow-brown to orange-brown, sometimes with dusty appearance, often with darker brown patterning on scutellum ( Fig. 3d ), sometimes with red highlighting, jugal margins, anterolateral margins of pronotum and embolium most often contrastingly paler yellow. Head: uniformly yellow-brown, punctures either fuscous or with green iridescence; underside of head yellow; antennae, AI yellow, AII-AIV yellow-brown to orange-brown; labium yellow to yellow-brown distally, with stylets black. Pronotum: pale red fasciae submarginal to anterolateral margins; callosite region sometimes with pair of small submedial spots. Hemelytra: exocorium and base of clavus with dark punctures, often with green iridescence, exocorium sometimes with pale red longitudinal fascia. Scutellum: posterolateral margins with fuscous punctures, often with green iridescence. Legs: uniformly yellow-brown to orange-brown. Thoracic pleura and abdominal sterna: uniformly yellow-brown, often with red spotting.

Texture. Body densely punctate, punctures shallow; mostly evenly distributed, linearly arranged on head, absent from callosite region and anterolateral margins of Pronotum.

Vestiture. Dorsum glabrous; underside of body almost glabrous, with scattered distribution of short, simple setae on abdominal venter, more so caudally. Antennae: AI-AII near glabrous; AIII-AIV with moderate distribution of short simple semierect setae. Legs: sparse distribution of simple short semierect setae.

Structure. Antennae: AIII and AIV subequal, longest antennal segments. Labium: reaching anterior margin of metacoxae. Abdominal Venter: males with sternal glands on abdominal SIV-VI ( Figs 2 a-c). Male Genitalia: pygophore lozenge shape ( Figs 7e, f , 8a ); ventral margin of pygophore arcuate ( Fig. 7e ); parameres with strongly hooked crown, with flange at base of crown ( Fig. 8b ); CAI absent ( Fig. 8c ); paired CAII asymmetrical ( Fig. 8c, d ), greatly enlarged, mostly membraneous, distally bifurcate, right CAII(L) with enlarged, sickle-shaped lobal sclerite, right CAII(M) with blunt bifid lobal sclerite, left CAII(L) with moderately-sized, arcuate lobal sclerite, left CAII(M) bifid with short subdistal acute lobal sclerite and small apical serrate lobal sclerite; CAIII small ( Fig. 8c, d ), flange-shaped, fused, heavily sclerotized, vesica extending beyond conjunctival appendages. Female Venter: posterior margin of SVII bisinuate, medially thickened. Female Terminalia: paratergites VIII large, medial margins broadly contiguous. Spermatheca: fecundation canal short, proximally incrassate and heavily sclerotized; and, spermathecal bulb oval, heavily sclerotized.

Measurements. MCDONALD & CASSIS 1984: Table 1 .

Type material examined: Coleotichus unicolor DALLAS : Holotype, ♂, ‘ North Coast of New Hol-land’ [label data as ‘New Holl’], ‘B.M. Hem. Type No. 364’, ‘ unicolor DALLAS’ ( BMNH).

Other material examined: Queensland: 2♀♀, 146 km NW Quilpie . 25:858S 143.399E, 230m, G Cassis, RT Schuh & R Silveira, 3 November 1998, ex Acacia stowardii MAIDEN, Site 98-20 ( AM) ; 3♂♂ 2♀♀, 73.7 km E Betoola , 25.591S 141.399E, 180m, G Cassis, RT Schuh & R Silveira, 3 November 1998, at light. ( AM) ; New South Wales: 1♂, Kinchega National Park , G Cassis, 28 April 1995, ex grass ( AM) ; 1♀, Kinchega National Park, Cawndilla Campground , 32°33’S 142°12’E, 100m, G Cassis & RT Schuh, 28 October 1995, Site 95-34, at light. ( AM) ; 2♂♂ 4♀♀, Moppin-Aveymore Road , 28°53’26“S 149°51’30“E, 400 m S of junction at Dolgelly Bore, R Harris & T Moulds, ex Acacia pendula ( AM) ; 15 km NE by N Moree , 29°20’S 149°56’E, 21 April 1981 ( ANIC) ; Australian Capital Territory: 52 specimens, Griffith , 17 February 1969, TG Campbell & CJ Shepherd, ( ANIC) ; Southern Australia: 1♀, Cadelga Homestead , 26.089S 140.410E, 150m, G Cassis, RT Schuh & Silveira, 4 November 1998, Site 98- 24, at light ( AM) ; 2♂♂ 2♀♀, Mt Serle district (near Gammon Ranges National Park ), 30°33’15“S 138°50’13“E, 567 m, 8 November 2001, RT Schuh, G Cassis, & M Schwartz, ex Acacia victoriae ( AM) ; Western Australia: 1♂, NW Coastal Highway , 36km N Kalbarri Road, 27.616°S 114.683°E, 500m, G Cassis & RT Schuh, 28 October 1996, Site 96-38, at light ( AM) ; 1♀, 20 km S of Menzies , G Cassis & RT Schuh, 28 October 1996 ( AM) ; 3♂♂ 6♀♀, Moorine Rocks , 11.7 km N Great Eastern Highway on Noongar Rd, 31.228°S 118.986°E, 345 m, RT Schuh, G Cassis, H Brailovsky & A Asquith, 4 December 1997, ex Acacia saligna (LABILL.) H.L. Wendl, Site 97-01 ( AM) ; 21♂♂ 33♀♀, 55.6 km SE Southern Cross , 31.589°S 119.592°E, 470m, RT Schuh, G Cassis, H Brailovsky & A Asquith, 4 December 1997, ex Acacia consanguinea R.S. Cowan & Maslin, Site 97-03 ( AM) ; 1♀, Pilbara District, Shay Gap Rd , 15.1 km NE Muccan Homestead, 20.222S 120.149E, 130m, G Cassis & R Silveira, 27 May 1999, at light. ( AM) ; 1♀, adjacent to N boundary of Lake Shaster Nature Reserve , 33.833°S 120.916°E, 40m, RT Schuh, G Cassis & R Silveira, 27 November 1999, ex Lambertia inermis, Site 99-42 ( AM) ; 2 larvae, Rossiter Bay, Cape Le Grande National Park , 3 m, 33°58.0345’S 122°16.0457’E, 23 November 1999, RT Schuh, G Cassis & R Silveira, Site SWA99-29, ex Acacia cyclops ( AM) ; 1♀, Walsh Point , 14.34 125.51E, 17 May 1983, I Naumann & JC Cardale ( ANIC) ; 5 specimens, Red Bluff , 28 November 1971, N McFarland, ex green pods of Acacia sp. ( ANIC) ; 3 specimens, Mt Magnet , 6 December 1978, K &E Carnaby ( ANIC) ; 2 specimens, 1 km W Jimberiana Hill, Norseman , 32°09’S 121°48’E, 11 January 1993, ED Edwards & ES Nielsen ( ANIC) .

Distribution: Coleotichus costatus occurs in arid and semi-arid regions of Australia, primarily in temperate Australia ( Fig. 6 ). It is also known from tropical Australia, including the Pilbara district of Western Australia and the wet tropics of Queensland. MCDONALD & CASSIS (1984) record it from the Northern Territory, although no precise localities are currently known. It has also been recorded from New Caledonia and Tonga ( CASSIS & GROSS 2002).

Host plant records and biology: Coleotichus costatus is known to feed on seven species of Acacia ( consanguinea , cyclops , ligulata , pendula , saligna , stowardii and victoriae ; Table 1 ) in Australia, primarily in semi-arid and arid regions. It can be abundant when the seed set of Acacia species is high (e.g. Southern Cross locality). It appears to be opportunistic and probably feeds on additional Acacia species, depending on seed availability. WHITNEY & STANTON (2004) report that C. costatus primarily feeds on Acacia ligulata in the Kinchega National Park in western New South Wales, but occasionally feeds on the seeds or fruits of Dodonaea viscosa (Whitney pers. comm.). The Lambertia inermis plant association ( Table 1 ) is probably a sitting record. As with other species of jewel bugs, GROSS (1975) reports that C. costatus can be found on the ground, but only occasionally on vegetation. Our observations do not support this contention, with C. costatus commonly encountered feeding on pre-dispersed seeds, upon plants.

Remarks: SCHOUTEDEN (1904) established the synonymy for Coleotichus costatus , which has been supported by all subsequent authors. GROSS (1975) redescribed this species including a habitus illustration. MC-DONALD & CASSIS (1984), also redescribed C. costatus , documenting the male and female genitalia for the first time. CASSIS & GROSS (2002) gave a comprehensive synonymy for the species.

Coleotichus costatus is best defined by the distinctive aedeagus, with the CAII asymmetrical ( Figs 8c, d ). This condition appears to be unique in the Scutelleridae , and even more generally within the Heteroptera. None-the-less the affinities of C. costatus are more with C. artensis , which possess fused CAIII (cf. C. excellens ; paired, segregated CAIII). In addition, the two former species are similar externally, with the body smaller, the ventral margin of the pygophore emarginate, and the base of the spermathecal fecundation canal heavily sclerotized.

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.

Fig. 7: Scanning electron micrographs of key characters of Coleotichus costatus (a) Head, dorsal view (b) Head, lateral view (c) Head and thorax, ventral view (d) External efferent system of metathoracic glands, ventral view (e) male pygophore, ventral view (f) male pygophore, dorsal view. Abbreviations: Ea = evaporative area; Ms(k) = mesosternal keel; Pe = peritreme; Pe(k) = proepisternal keel, ventral view; EES = external efferent system. Scale bars = 1 mm.

Fig. 8: Male genitalia of Coleotichus costatus (a) pygophore, dorsal view (b) paramere, lateral view (c) aedeagus, lateral view (d) aedeagus, ventral view. Abbreviations: C = crown of right paramere; CAII(L)L = left second conjunctival appendage, lateral branch; CAII(L)R = right second conjunctival appendage, lateral branch; CAII(M)L = left second conjunctival appendage, medial branch; CAII(M)R = right second conjunctival appendage, lateral branch; CAIII = third conjunctival appendage; DCC = dorsal conducting canal; DS(D) = ductus seminis dorsalis; DS(P) = ductus seminis proximalis; Er = ejaculatory reservoir; F = flange at base of crown of paramere; GO = genital opening; Pt = phallotheca; S = stem of paramere; Sg = secondary gonopore; V = vesica; VCC = ventral conducting canal of ejaculatory apparatus; VM = ventral margin of genital opening.

Fig. 4: Scanning electron micrographs of key characters of Austrotichus rugosus (a) Head, dorsal view (b) Head, lateral view (c) Head and thorax, ventral view (d) External efferent system of metathoracic glands, ventral view (e) male pygophore, ventral view (f) male pygophore, dorsal view. Abbreviations: C = clypeus; Ea = evaporative area; Go = genital opening; J = juga; Me = mesepimeron; Met = metepisternum; Ms(k) = mesosternal keel; Pe = peritreme; Pe(k) = proepisternal keel, ventral view; P(r) = right paramere; Pr = proctiger. Scale bars = 1 mm.

Fig. 5: Male genitalia of Austrotichus rugosus (a) pygophore, dorsal view (b) right paramere, lateral view (c) aedeagus, lateral view (d) aedeagus, ventral view. Abbreviations: C = crown of paramere; CAII(L) = second conjunctival appendage, lateral branch; CAII(M) = second conjunctival appendage, medial branch; CAIII(D) = third conjunctival appendage, dorsal branch; CAIII(V) = third conjunctival appendage, ventral branch; DCC = dorsal conducting canal; DS(D) = ductus seminis dorsalis; DS(P) = ductus seminis proximalis; F = flange at base of crown of paramere; GO = genital opening; Pt = phallotheca; S = stem of paramere; Sg = secondary gonopore; V = vesica; VCC = ventral conducting canal of ejaculatory apparatus; VM = ventral margin of genital opening.

Fig. 9: Scanning electron micrographs of key characters of Solenotichus circuliferus (a) Head, dorsal view (b) Head, lateral view (c) Head and thorax, ventral view (d) External efferent system of metathoracic glands, ventral view (e) male pygophore, ventral view (f) male pygophore, dorsal view. Abbreviations: Ea = evaporative area; Ms(k) = mesosternal keel; Pe = peritreme; P(r) = right paramere. Scale bars = 1 mm.

Fig. 2: Abdominal Sternal Glands of Scutelleridae (a-c) Coleotichus costatus (a) abdominal venter, sternal glands on SIV-SVI (b-c) higher magnification of sternal glands (d-f) Morbora schoutedeni (d) androconial glands on SIV-SVI (e) higher magnification of microsculpture medial to androconial glands (f) higher magnification of apex cuticular duct of glandular unit of androconial glands (g-i) Tectocoris diophthalmus (g) androconial glands on SIV-SVI (h) higher magnification of androconial glands on abdominal SVI (i) higher magnification of apex of cuticular ducts of glandular units of androconial glands. Abbreviations: Ag = Androconial glands; Cd = cuticular ducts; Sg = sternal glands. Scale bars = 0.1 mm.