Adraneothrips Hood

Dang, Li-Hong, Mound, Laurence A. & Qiao, Ge-Xia, 2013, Leaf-litter thrips of the genus Adraneothrips from Asia and Australia (Thysanoptera, Phlaeothripinae), Zootaxa 3716 (1), pp. 1-21 : 2-4

Adraneothrips Hood

Adraneothrips Hood, 1925: 54 . Type species: Haplothrips tibialis Hood , by original designation. Stigmothrips Ananthakrishnan, 1964: 231 . Type species: Stigmothrips limpidus Ananthakrishnan, 1964 , by original designation. syn.n.

Baphikothrips Mound, 1970: 90. Type species: Baphikothrips antennatus Mound, by original designation. Synonymised with Stigmothrips by Okajima, 1976.

The genus Adraneothrips was erected by Hood (1925) for four species from the West Indies, and most of the described species are Neotropical. Mound & Marullo (1996) listed 59 New World species in this genus and provided a key to 32 of these. Okajima (1976) indicated that Stigmothrips is similar to Adraneothrips , sharing such character states as slender antennal segments, long maxillary stylets, and absence of basantra. Moreover, he suggested that Stigmothrips might be considered a subgenus of Adraneothrips , although in 2006 he suggested that it could be treated as a synonym of Adraneothrips . Mound & Marullo (1996) indicated that the New World species of Adraneothrips seemed to represent three divergent groups, the alternatus -group, bellus -group and uniformis - group. Species of the bellus -group are distinguished because the eyes are prolonged ventrally on the head. Species of the uniformis -group are distinguished because the maxillary stylets are long and close together medially in the head. Stigmothrips species are particularly similar to species of the alternatus -group, the only difference being that species of Stigmothrips have the notopleural sutures incomplete or almost incomplete, whereas these are complete in species of the alternatus -group.

The original description of Stigmothrips does not mention the prothoracic notopleural sutures and the only illustration is unclear. However, as listed below, specimens of both sexes identified by Ananthakrishnan as limpidus have these sutures clearly incomplete ( Fig. 37 ). In specimens from Australia that are here identified as russatus and coloratus , the notopleural sutures are variable, from clearly incomplete to almost complete, and they are not always bilaterally symmetrical. Thus Stigmothrips cannot be distinguished satisfactorily from Adraneothrips and these are here placed into synonymy. Species of this genus commonly share a character state that is unusual among Phlaeothripinae , in that the pair of accessory setae on tergite IX between the major setae S1 and S2 are long ( Figs 38, 39 ). This also occurs in several Australian species of Hoplandrothrips (Mound & Tree 2013) . Despite the absence of the metathoracic sternopleural sutures in Adraneothrips species, these two genera are possibly related (Mound et al. 2013), although the species of Adraneothrips exhibit little of the sexual polymorphism that is so common among Hoplandrothrips species.

Diagnosis. Head with cheeks slightly constricted behind large eyes; postocular setae usually arise behind inner margin of eyes ( Figs 16–25 ); stylets usually about 1/3 of head width apart, retracted to postocular setae; antennae 8-segmented, III with 2 or 3 sensoria, IV with 3 or 4 (rarely 2); pronotum with 5 pairs of capitate setae, notopleural sutures incomplete or complete; basantra absent, mesopraesternum transverse; metathoracic sternopleural sutures absent; fore tarsal tooth usually not developed; fore wings weakly constricted medially, with or without duplicated cilia; pelta usually longer than wide ( Figs 26–30 ) and bell-shaped; tergites II–VII with 2 pairs of wing-retaining setae, each posterior pair usually thicker than anterior pair ( Figs 27, 28 ); tergite IX with accessory setae between S1 and S2 almost as long as S1 ( Figs 38, 39 ); tube with straight sides, slightly shorter than head; male sternite VIII with or without pore plate ( Figs 33–36 ).

Figures

FIGURES 33 – 39. Adraneothrips species. Male sternite VIII 33 – 36: (33) braccatus; (34) chinensis; (35) makilingensis; (36) russatus. (37) limpidus pronotum. Chaetotaxy of tergite IX 38 – 39: (38) hani male; (39) limpidus female.

FIGURES 16 – 21. Adraneothrips heads. (16) braccatus; (17) chinensis; (18) coloratus; (19) darwini; (20) hani; (21); makilingensis.

FIGURES 22 – 25. Adraneothrips heads. (22) nilgiriensis; (23) russatus; (24) waui; (25) yunnanensis.

FIGURES 26 – 32. Adraneothrips metanota and tergites. (26) braccatus; (27) coloratus; (28) darwini; (29) russatus; (30) hani; (31) waui; (32) yunnanensis.