Adrothrips vernoni, Mound & Tree & Wells, 2022

Mound, Laurence A., Tree, Desley J. & Wells, Alice, 2022, Convoluted maxillary stylets among Australian Thysanoptera Phlaeothripinae associated mainly with Casuarinaceae trees, Zootaxa 5190 (3), pp. 301-332 : 313-315

Adrothrips vernoni sp.n.

( Figs 8 , 20, 26 , 31, 38 )

Female macroptera. Body brown, basal half of tube usually paler; tarsi and apices of tibiae yellow; antennal segment III and apex of II paler than remaining segments; fore wing pale and weakly sclerotised; major setae all translucent. Head longer than wide with posterior margin slightly eroded; postocular setae capitate usually reaching to eye margin; vertex weakly reticulate. Maxillary stylets retracted to eyes, parallel or slightly crossing over each other medially, with one flexure before entering mouth cone ( Fig. 20 ). Antennal segment III small, about as wide as long ( Fig. 8 ), with no sense cone, IV with 2 stout sense cones, apex of V asymmetric with one short stout sense cone and one small sense cone on inner apex. Pronotum with little reticulation medially but with transverse reticulation on posterior third, all five pairs of major setae capitate. Metanotum weakly reticulate, reticles with few internal markings, bearing 10 small setae ( Fig. 26 ). Fore tarsal tooth large, about as long as tarsal width, hamus also prominent ventrally. Prosternal ferna with anterior margin transverse; mesopresternum weakly sclerotised, occupying median third of, and partially fused to, anterior margin of mesoeusternum ( Fig. 31 ); metathoracic sternopleural sutures broadly eroded. Pelta broadly triangular, reticulate; tergites II-VII each with only posterior pair of wing-retaining setae; tergite IX setae capitate and shorter than basal width of tube; tube broader in basal than in apical third ( Fig. 38 ).

Measurements (holotype de-alate female in microns). Body length 1700. Head, length 160; width medially 150; po setae 15. Pronotum, length 145; width 250; prothorax width across coxae 350; major setae – am 18, aa 25, ml 12, epim 35, pa 35. Fore wing length?; sub-basal setae 12, 20, 35. Tergite IX setae S1 50, S2 50. Tube, basal width 65, length 75. Antennal segments III–VIII length 30, 45, 43, 45, 40, 25.

Female microptera. Very similar to macroptera but ocelli slightly smaller; fore wing length 120.

Male microptera. Similar to female but fore tarsal tooth not as large; sternites without transverse bands of specialised reticulation.

Specimens studied. Holotype female de-alate macroptera, South Australia, Kangaroo Island, American River , on Allocasuarina verticillata , 31.iii.2021 ( LAM6477 ) in ANIC.

Paratypes (female micropterae except where indicated); same site and host as holotype, Kangaroo Island , 4 on 29.xi.2021 , 1 on 3.iv.2021; Stokes Bay , 2 on 30.xi.2021 ; Destrey’s Bay Road, Allocasuarina muelleriana , 1 female on 1.xii.2021 . New South Wales, Bermagui , 1 female from dead bark, 20.iii.1991 . Australian Capital Territory, Canberra , on A. verticillata: Mt Stromlo , 4 on 25.xii.2021 , 3 on 1.i.2022, 1 male 1 female macroptera on 4.ii.2022; Oakey Hill , 8 females, 2 males, 29.xi.2002 ; Mt Ainslie , 1 female macroptera, 4 females, 2 males with larvae from woody gall, 11.vi.1995 .

Comments. Despite multiple efforts over the past 30 years in the hills around Canberra, only a single gall has ever been found that included a breeding colony of this species. Most available specimens are micropterae and have been obtained only by beating the trees for prolonged periods, with no obvious association with either the green or woody tissues. This species is remarkable for the large fore tarsal tooth ( Fig. 20 ) and the small third antennal segment ( Fig. 8 ). It appears to be closely associated with A. verticillata , with only a single female ever taken from a different species.

Figures

FIGURES 2–10. Adrothrips species antennae. (2) aureus; (3) cotteri; (4) intermedius; (5) latrarei; (6) lihongae; (7) madiae; (8) vernoni; (9) westoni; (10) mitchelli.

FIGURES 20–27. Adrothrips heads, metanotum & pelta. (20) vernoni holotype; (21) mitchelli holotype; (22) aureus; (23) intermedius; (24) latrarei; (25) madiae; (26) vernoni; (27) systenus.

FIGURES 28–39. Adrothrips prosternites and abdomen. (28) cotteri; (29) latrarei; (30) lihongae; (31) vernoni; (32) akanthus; (33) aureus; (34) cotteri; (35) intermedius; (36) mitchelli; (37) systenus; (38) vernoni; (39) westoni.