Body yellowish brown, head and abdominal apex darkest; antennae brown, antennal segment III palest; fore wing grey. Antennae 7-segmented, segment III shorter than IV, both with forked sense cones. Head clearly longer than wide, projecting slightly in front of eyes; ocellar setae pair I present, postocular setae in a transverse row. Pronotum with transverse lines of sculpture, with two pairs of posteroangular setae; metanotal median setae arising close to anterior margin. Abdominal tergites without ctenidia, tergite X with a median longitudinal split. Sternites without discal setae.
Male not known.
Intraspecific variation
Not recorded.
Genus and similar species information
There are 17 species listed in Plesiothrips, mostly light brown to yellowish brown with grey fore wings. All of them live on grasses, and the genus represents a radiation that is unique to the American continent. They all have the ovipositor weak with serrations almost absent, which suggests that they possibly deposit their eggs within grass flowers, rather than into plant tissues. Possibly related to the genus Thrips due to having a similar position of the rudimentary ctenidia on tergites VI & VII, and absence of ocellar setae pair I. Plesiothrips sculpticollis is one of two species in the genus with a pair of setae in front of the first ocellus, but unlike P.longicollis the head and pronotum bear many transverse lines of sculpture. A key to Plesiothrips species is given by Mound et al. (2016).
Hood JD (1950) Brasilian Thysanoptera II. Revista de Entomologia 21: 1–113.
Mound L, Lima E, O’Donnell C, Cavalleri A (2016) New World grass thrips of the genus Plesiothrips (Thysanoptera: Thripidae). Austral Entomology 55: 340–346.
Published in: 30/12/2016 Posted by: Mariana Lindner
