Oxythrips Uzel

Masumoto, Masami & Okajima, Shûji, 2017, Anaphothrips genus-group: key to world genera, with two new species and three new records from Japan (Thysanoptera, Thripidae), Zootaxa 4272 (2), pp. 201-220 : 211

Oxythrips Uzel

Oxythrips Uzel, 1895: 133 . Type species: Oxythrips ajugae Uzel 1895 , by subsequent designation, Hood 1916: 37.

Female. Wings fully developed. Mouth-cone often elongate, with 3-segmented maxillary palpi. Compound eyes usually with six pigmented facets ventrolaterally. Ocellar setae pair I present, pair III relatively well-developed. Postocular setae four pairs arranged transversely. Antennae 8-segmented, but segment VI often with weak transverse line, I without median dorsal apical setae, III and IV each with forked sensorium, III–VI with some microtrichial rows on both dorsal and ventral surfaces. Pronotum with one pair of posteroangular setae ( Fig. 17 ). Mesonotum with median pair of setae far from posterior margin ( Fig. 20 ). Metascutum reticulate medially; median pair of setae far from anterior margin; CPS present. Metapre-episternum ( Fig. 21 ) weakly developed and with one seta. Prosternal ferna slightly divided at middle; basantra membranous, without setae; prospinasternum broad and transverse. Spinula present on mesosternum, but absent from metasternum. Fore wing first vein with long gap in setal row, but often irregularly spaced, second vein with many setae irregularly spaced; clavus with 5 (rarely 4) veinal and one discal setae; posteromarginal fringe cilia wavy. Fore tibia usually without stout setae at apex ( Fig. 22 ), often with apical inner tubercles. Tarsi 2-segmented, often with inner apical claw. Abdominal tergites without ctenidia and posteromarginal craspeda ( Fig. 24 ); tergites II–VII with S3 setae (posteroangular setae) inserted at or near posterior angle; tergite VIII usually without posteromarginal comb; tergite IX with MD setae small; tergite X with median longitudinal split distally; sternites ( Figs 25–26 ) without posteromarginal craspeda; sternites III, III– IV, III–V or VI often with one or two pore plates; sternites III–VII with 3 pairs of posteromarginal setae, but II with 2 pairs, VII with S1 setae in front of posterior margin; pleurotergites with setae arising from posterior margin only. Ovipositor well-developed.

Male. Abdominal tergite IX ( Fig. 27 ) with 2 pairs of stout and short setae medially, sternites III–VI each with a large circular pore plate ( Fig. 28 ).

Comments. Oxythrips includes 39 species in the world, but with none from the Ethiopian region . There are 24 from the Palaearctic region, two from India, 10 from the Nearctic, one from Chile, and two from Australia of which one is recently transferred to a new genus Paroxythrips ( Masumoto & Okajima 2017) ( Table. 1). However, several species in the southern hemisphere are slightly divergent in morphology ( Mound & Tree 2011). Oxythrips species have basically the same morphological structure as Chilothrips species that are associated with flowers of Pinus in North America and Asia, also as Anaphothrips species that are usually grass-living. Females of Oxythrips often have pore plates on one or more abdominal sternites as in Chilothrips . Stannard (1973) discussed relationships between these genera, and referred to differences between them. Females of Chilothrips differ from those of Oxythrips in having the mouth-cone broad and long, reaching the mesosternum, and at least a stout spine-like seta at the ventral apex of the fore tibia. However, Oxythrips species usually have the mouth-cone not reaching the mesosterum, and the fore tibia apical setae not spine-like. In contrast, Anaphothrips differs from Oxythrips in having the pronotum with no long posteroangular setae, and many species have abdominal tergite VIII with a posteromarginal comb.

Figures

FIGURES 17 – 28. Oxythrips japonicus sp. n. Female 17 – 26. (17) Head & pronotum; (18) Antenna; (19) Antennal segments VI – VIII, ventral aspect, setae and sxulpture omitted; (20) Mesonotum & metascutum; (21) Metapre-episternum, left; (22) Fore tarsus to distal part of tibia, right; (23) Tergite II; (24) Tergites VII-X; (25) Sternites II – IV, sculpture omitted; (26) Middle of sternite III. Male 27 – 28. (27) Tergite IX; (28) Sternite VI, sculpture omitted.