Thaumastocoris australicus Kirkaldy, 1908

Noack, Ann E., Cassis, Gerasimos & Rose, Harley A., 2011, Systematic revision of Thaumastocoris Kirkaldy (Hemiptera: Heteroptera: Thaumastocoridae), Zootaxa 3121, pp. 1-60 : 25-27

Thaumastocoris australicus Kirkaldy, 1908

(Figures: 3A,B; 18A)

Thaumastocoris australicus Kirkaldy 1908: 778 ; Drake and Slater 1957: 366 (description); Kumar 1964: 48 (morphology); Rose 1965: 141 (diagnosis); Slater 1973: 155 (taxonomy); Cassis and Gross 1995: 393 (catalogue); Cassis, Schuh and Brailovsky 1999: 28 (diagnosis; host plants); Carpintero and Dellapé 2006: 67 (diagnosis).

Neotype: 3, QUEENSLAND, Mt. Coot-tha, 27-6-1927, H Hacker. ‘ Thaumastocoris australicus Neotype Kirk,’ ‘ NEOTYPE Thaumastocoris australicus Kirk. C.J. Drake, J.A. Slater’ (USNM 63462 Type No.).

Other material examined. NEW SOUTH WALES: 1Ƥ, 4.5 km S of Pottsville Beach, sea level, 28°25’52”S 153°33’27”E, 29 October 1998, RT Schuh, G Cassis, R Silveira, locality code NSW 98-L01-H3, ex Acacia saligna (Labill.) H.L. Wendl. ( Fabaceae : Mimosoideae ) ( NSW 427618) (AM). QUEENSLAND, 131Ƥ, Brisbane 11.xi.1964, HA Rose (QM); 1Ƥ, Brisbane, 8.vii.1962, K Barnard (QM); 1Ƥ, Brisbane, 22.iv.1963, G Monteith (QM); 1Ƥ, Brisbane, 5.x.1962, G Monteith (QM); 23, Carnarvon Range, Upper Bullaroo Creek, 3.vi.1954, TE Woodward, ex Wattle (QM); 13, Dalby 29.v.1964. J Wilson, ex sweeping (QM); 23, Mulgowie, ex Eucalyptus maculate , open forest, MD Peart, A487, 28.ix.1981 (QM); 434Ƥ, Saddletree Creek, via Maidenwell, SE Qld, A Postle, 12–14.iii.1976 (QM).

Diagnosis. Thaumastocoris australicus is recognised by the following characters: mandibular plates strongly flared laterally, eyes strongly pedicellate; labium very short, reaching anterior margin of prosternum; prosternum strongly swollen anteriorly; weak pronotal constriction, with disc wider than callosite region; abdomen expanded laterally, visible beyond costal margins of hemelytra ( Figure 3 A,B). It can be distinguished from T. nadeli and T. peregrinus by the strongly flared mandibular plates and weakly constricted pronotum. In particular, the pronotum of the last two species is strongly constricted (cf. Figure 6 A,B; 7A,B). In addition, the prosternum in these species is flat and not swollen, as in T. australicus (cf. Figure 13 B).

Redescription. Submacropterous. Male length 2.53–2.77, width 0.86–0.98; female length 2.61–2.92, width 1.91–1.11. Females slightly larger in size, with slightly more expanded abdomen. Colouration. Dorsum pale brownish yellow with contrasting dark brown to fuscous markings ( Figure 3 A,B). Head: mostly yellowish brown; vertex more yellow; lateral aspect of mandibular plates and genae cream. Antennae: mostly yellowish brown; subapical third of AIII and AIV dark brown. Labium: LI–LIII yellowish brown; apex of LIV light brown. Pronotum: mostly yellowish brown, disc paler than callosite region. Thoracic sterna: prosternum cream, mesosternum fuscous paler laterally. S cutellum: dark brown to fuscous anteriorly, paler posteriorly. Hemelytra: mostly yellowish brown, basal third of medial margin of endocorium dark brown; membrane sometimes with basal third and apical half dark brown, otherwise apically infused with light brown. Legs: mostly straw-coloured, second tarsomere dark brown. Abdominal venter: fuscous medially, yellowish brown laterally. Texture. Dorsum moderately polished, with scattered, shallow to deep, setose punctures. Head: vertex mostly impunctate, sometimes with transverse puncticulate rows visible; epicranial suture with irregular distribution of shallow punctures; mandibular plates irregularly punctate, denser posteriorly, punctures shallow. Pronotum: callosite region sparsely puncticulate, denser along midline and anterolateral angles; calli polished; disc densely and regularly punctuate , punctures moderately deep, posterolateral angles impunctate. Thoracic pleura and sterna: thoracic pleura with irregular shallow punctuation; propleuron with submarginal row of large, shallow punctures posteroventrally; thoracic sterna mostly with sparse, irregular punctuation; mesosternum strongly polished. Scutellum : densely and regularly punctate, punctures deep, midline polished posteriorly. Hemelytra: clavus with uniform distribution of deep punctures; corium with irregular distribution of deep punctures, punctures larger than on pronotal disc ( Figure 3 A,B). Abdominal venter: impunctate, moderately polished. Vestiture. Dorsum with uniform distribution of setose punctures, setae short, erect, strawcoloured; without other vestiture. Ventral surface with fine, straw-coloured, decumbent setae, most densely distributed on ventral aspect of mandibular plates, proepisternum, and medially proepimeron; thoracic sterna moderately polished. Antennae: with uniform distribution of decumbent setae, intermixed with fine, erect setae; AII–AIV with similar setae on lateral margins, otherwise bare. Male genitalia: pygophore with irregular distribution of fine seta; pygophoral lock with irregular distribution of setae, more sparse basally, margins bare; paramere evenly beset with fine setae ( Figure 18 A). Structure. Head: mandibular plates elongate, surpassing clypeus by less than clypeal length, contiguous medially, flared anteriorly, concave dorsally, lateral margins strongly flared, moderately recurved; bucculae strongly arcuate; gula distinctly concave. Eyes: moderately pedicellate. Antennae: AI and AIII cylindrical; AII slightly expanded distally; AIV weakly lanceolate. Labium: very short, just reaching anterior margin of prosternum. Pronotum: weakly constricted medially; callosite region and disc subequal in length, disc distinctly broader; callosite region weakly depressed along midline; anterolateral angles weakly tuberculate to rounded; lateral margin of disc weakly arcuate ( Figure 3 A,B). Thoracic sterna: prosternum distinctly swollen and truncate anteromedially; posterolateral margins of prosternum weakly flared. Hemelytra: at rest extending to caudal half of pygophore; medial margin of corium straight to weakly convex; apex of corium at membrane moderately narrowed, medial margin less than 45° to costal margin. Legs: forecoxae subequal to slightly wider than coxal width; fore and mesofemora incrassate; fossula spongiosa elongate, reaching distal margin of second tarsomere; 6– 7 fore and mesotibial teeth, 3–4 metatibial teeth. Male Genitalia: pygophoral lock flat and broad basally, weakly concave medially, weakly arcuate apically; paramere ovoid ( Figure 18 A).

Measurements. See Table 2.

Distribution. Thaumastocoris australicus is known from southeast Queensland and north eastern New South Wales ( Figure 20 A).

Host plant. Thaumastocoris australicus has been collected from three species of Acacia and a single species of Eucalyptus ( Table 3 ).

Remarks. Thaumastocoris australicus was described by Kirkaldy (1908) from a single carded specimen collected from Bundaberg, Queensland. He erected the subfamily Thaumastocorinae to accommodate it, within the family Lygaeidae . Reuter (1912) elevated the subfamily to family status. Kirkaldy first named the genus as Thaumastotherium , but in the same publication, as Thaumastocoris in the legend for the plate of illustrations, and in a corrigenda page. Drake and Slater (1957) clarified the name as Thaumastocoris by page priority (Article 19, Copenhagen Decisions on Zoological Nomenclature). They also erected a neotype on the suspicion that the holotype had been lost during illustration ( Drake and Slater 1957).

This species has been collected from south east Queensland and northern New South Wales. It has been collected on Acacia species. Cassis et al. (1999) expanded the host range of this thaumastocorid species to include Eucalyptus species, from collections made in central south east Queensland and South Australia, although questioning the conspecifity of these bugs. We have not been able to locate the Queensland specimens collected on E. populnea populnea to confirm their identity as T. australicus . However, the South Australian specimens from E. costata and E. porosa were misidentified as T. australicus by Cassis et al. (1999); in this work they represent two new species, T. freomooreae and T. ohallorani , respectively. Cassis et al (1999) excluded a number specimens collected from New South Wales, Victoria, and Western Australia from their consideration of T. australicus , stating that this material, although very similar to T. australicus , probably represented new Thaumastocoris species. In total, four new species was represented in the material identified as T. australicus by Cassis et al. (1999). Kumar (1964) successfully raised T. australicus on Acacia cunninghami in the laboratory and investigated their internal morphology. Unique to T. australicus is a very short labium which abuts the swollen truncate anterior margin of the prosternum.

Figures

FIGURE 3. Habitus, dorsal view. A and B Thaumastocoris australicus. C and D Thaumastocoris busso. Scale bar = 1 mm.

FIGURE 6. Habitus, dorsal view. A and B Thaumastocoris nadeli. C and D Thaumastocoris ohallorani. Scale bar = 1 mm.

FIGURE 13. Scanning electron micrographs: Thaumastocoris nadeli. A 3 head and pronotum, dorsal view. B 3 head and pro sternum, ventral view. C 3 antenna, dorsal view. D 3 head and propleura, lateral view. E 3 thorax, lateral view. F 3 midtarsus, lateral view. G 3 genitalia, ventral view. H Ƥ genitalia, ventral view. tt = tibial tooth. Scale bar = 0.1 mm.

FIGURE 18. Male genitalia. A. Thaumastocoris australicus, ventral view B. Thaumastocoris busso, ventral view C. Thaumastocoris freomooreae, ventral view D. Thaumastocoris majeri, ventral view E. Thaumastocoris hackeri, ventral view F. Thaumastocoris hackeri, dorsal view G. Thaumastocoris ohallorani, ventral view H. Thaumastocoris ohallorani, dorsal view. Scale bar = 0.1 mm.

FIGURE 20. Distribution map. A. Thaumastocoris australicus, T. busso, T. freomooreae and T. hackeri B. Thaumastocoris kalaako, T. majeri, T. macqueeni and T. nadeli.