Stephanothrips howei Mound & Tree 2018, sp.n.

Stephanothrips howei sp.n.

(Figs 3, 8, 14)

Female aptera. Bicoloured (Fig. 3); dark brown head, pronotum, mesonotum, fore and mid coxae; white fore femora and antennal segments II–V, but VI–VIII brown; all tibiae with light brown band medially; mid and hind femora variable from almost white to light brown; abdominal tergites with light brown areas laterally but pale medially, tube yellow. Head slightly longer than wide, cheeks weakly concave behind eyes (Fig. 3); vertex with many equally small tubercles; compound eyes with 3 large facets and mesad of these a row of about 7 smaller facets; anterior margin with 3 pairs of prominent setae with broadly capitate apices, arising from prominent tubercles; maxillary stylets retracted to eyes, parallel medially and about one third of head width apart. Antennal segments III–V fused without sutures (Fig. 8), VII–VIII fused but with partial suture ventrally. Pronotum with many small tubercles posterolaterally, epimeral setae short with broadly expanded apices. Fore tarsi with prominent hamus on external margin. Metanotum weakly joined to tergite I medially; suture between tergites I and II slender (Fig. 14); tergites II and III each with transverse row of about 20 small setae; tergite X dorsal setal pair about two-thirds as long as the other 4 anal setae.

Measurements (holotype female in microns). Body length 1450. Head, length 170; width 145; anteromarginal setae, inner 60, outer 50. Pronotum, length 100; width 175; epimeral setae 20. Tergites VIII, IX & X lengths 60, 135, 275; lateral anal setae 650. Antennal segments length 65 [III+IV+V]; 25 [VI]; 45 [VII+VIII].

Male not known.

Material studied. Holotype female, Australia, Lord Howe Island, Stevens Trail, from dead branches, 26.xii.2001 (LAM 4086), in ANIC.

Paratypes: 1 female taken with the holotype; Queensland, Lamington, O’Reilly’s, dead branches, 1 female 11.x.2006, 1 female 4.viii.2013; Mt Glorious, 1 female from Cyathea fronds, 18.i.2006. New South Wales, Harrington, 1 female from Podocarpus, 10.xii.2001.

Comments. Among the 32 species now placed in Stephanothrips, this is only the fourth to be described as having a prominent hamus on the external margin of the fore tarsi. Stephanothrips occidentalis is generally recognised because of the possession of this structure, but a rather similar structure is described for S. thai from northern Thailand, and S. zonatus from Bali, Indonesia. In contrast to the common worldwide species, occidentalis, this new species has each compound eye with an extra row of small facets medially, and tergites I and II are not fused together. Moreover, antennal segments III+IV+V are more closely fused in howei than in occidentalis. Species of Stephanothrips usually have each compound eye with a single row of facets, but the extra row of smaller facets described here in howei is a character state that is shared with some species in the related urothripine genus Bradythrips.