Polytrichothrips geoffri, Mound, Laurence A., 2007

Mound, Laurence A., 2007, New Australian spore-feeding Thysanoptera (Phlaeothripidae: Idolothripinae), Zootaxa 1604, pp. 53-68 : 64-65

Polytrichothrips geoffri sp.n.

( Figs 19–23 )

Apterous female. Body and legs brown to dark brown, tube almost black, antennal segments III–V paler at base; major setae brown. Head longer than wide; cheeks almost parallel, with about 6 stout setae, and ventrolaterally in posterior fifth with pair of clear ommatidium-like structures; maxillary stylets broad, retracted to eyes and close together medially; postocular setae long, ocellar setae small ( Fig. 19 ); mouth cone broadly rounded. Antennae 8-segmented, III with two sensoria, IV with four sensoria, VIII narrowed to base. Pronotum short and trasverse, with four pairs of long, finely pointed major setae, anteromarginals short; epimeral setae on small tubercles, epimeral sutures complete. Prosternal basantra transverse, ferna large and pointed medially; mesopraesternum slender and transverse; metathoracic sternopleural sutures not developed. Fore tarsus with prominent, curved lateral tooth. Metanotum transverse, with no sculpture, median setae slender. Pelta broad, with little sculpture ( Fig. 22 ); tergites without sculpture; posteroangular tergal setae on II–IV shorter than tergites, on VI–VII much longer than tergites, on IX as long as tube. Sternites without discal setae, prominent transverse row of pores present in front of antecostal ridge.

Measurements of holotype female in microns. Body length 2600. Head, length 350; width 270; postocular setae 140. Pronotum, length 160; width 400; major setae am 25, aa 85, ml 80, epim 125, pa 120. Metanotum median setae 35. Tergite IX setae S1 270, S2 270. Tube, length 280; anal setae 150. Antennal segments III– VIII length, 90, 90, 90, 75, 55, 55.

Macropterous female. Head with cheeks almost straight, narrowing to base; ocelli well-developed ( Fig. 20 ); mesonotal lateral setae minute; metanotum without sculpture medially, median setae small and slender; forewing with three sub-basal setae, S2 arising posterior to S1, with 15 duplicated cilia; pelta broad, with a few lines of sculpture at anterior margin and laterally; tergites without sculpture, with one pair of almost straight wing-retaining setae.

Measurements of macropterous female in microns. Body length 3050. Head, length 390. Forewing length 1350. Tergite IX setae S1 350. Tube, length 380. Antennal segments III–VIII length, 105, 105, 100, 85, 55, 55.

Apterous male. More robust than apterous female; head with at least 12 pairs of cheek setae, ocelli very small. Pronotum ( Fig. 21 ) with anterior and posterior margins thickened, median apodeme strong; prosternal ferna massive with curved anterior margins; coxae protruding laterally with a stout terminal seta; fore femora enlarged and curved; fore tibia with two small tubercles on inner margin, one subterminal and one terminal; fore tarsal tooth longer than tarsal width; sternites with small discal setae.

Measurements of apterous male in microns. Body length 2850. Head, length 400; width 300; postocular setae 200. Pronotum, length 250; width 530; width across coxae 800; major setae am 30, aa 125, ml 175, epim 130, pa 130. Metanotum median setae 50. Tergite IX setae S1 300, S2 300. Tube, length 320; anal setae 160. Antennal segments III–VIII length, 95, 95, 95, 75, 55, 55.

Material studied. Holotype female aptera, Queensland, 12km west of Bartle Frere Summit, 17°26' 145°42', from logs by pyrethrum spraying, 4.xii.1993 (Montieth), in Queensland Museum.

Paratypes, all taken by pyrethrum spraying of logs: 2 female aptera collected with holotype; 1 female aptera, 17°36' 145°42', 18.v.1995; 2 male apterae, 13km west of Mossman, Paul’s Luck, 16°26' 145°15', 29.xi.1990; 1 male aptera, 16°22' 145°15', 18.x.1991; 1 female aptera, 1 female macroptera, 38km north west of Mossman, 16°16' 145°03', 8.i.1989.

Comments. The genus Polytrichothrips Priesner currently includes only one species, P. laticeps (Bagnall) , of which there is also one synonym, and the species is known only from the two holotypes, both of which are macropterous females that were collected in Sarawak ( Mound & Palmer, 1983). In P. laticeps the head is slightly longer than in the new species described here (1.5 rather than 1.4 times as long as wide), and the cheeks are distinctly convex. Moreover, the head bears a pair of prominent postocellar setae and also a pair of prominent mid-vertex setae, from which the generic name is derived. Despite these differences, the other character states of the macropterous female of P. geoffri are essentially the same as those of P. laticeps , and there seems little justification for erecting a further monobasic genus for the Australian species. Amongst the other Macrothripina, the Indonesian species Diaphorothrips clavipes Priesner has a similar ommatidium-like structure laterally on the head near the posterior margin, but the stylets are wide apart and the pelta of a different shape. Species of Celidothrips Priesner , of which two of the four are known from Australia, have an even longer head with an ommatidium-like structure immediately behind the compound eyes. Also similar in structure are South East Asian species in Dichaetothrips Hood and Tarassothrips Mound & Palmer , but these have much longer sensoria on the antennae and a different shaped pelta.

Figures

FIGURES 19 – 23. Polytrichothrips geoffri. 19, Female holotype; 20, Female macroptera; 21, Male; 22, Female aptera, metanotum to tergite III; 23, Antenna.