Stenchaetothrips spinalis Reyes, 1994

Ng, Y. F. & Mound, L. A., 2015, Species of Thripinae (Thysanoptera) from bamboo in Malaysia, with one new species and six new records, Zootaxa 3918 (4), pp. 492-502 : 499-500

Stenchaetothrips spinalis Reyes, 1994

( Figs 31–36 )

Female macroptera. Body light brown to brown; head, thorax usually paler than more uniformly brown abdominal segments; femora light brown; tibiae pale; legs pale; antennal segments brown, but III slightly paler; fore wing uniformly shaded ( Fig. 33 ). Head, about as long as wide; ocellar setae II longer than III; post-ocellar setae III longest ( Fig. 31 ). Pronotum with 20–22 discal setae, surface smooth with weak transverse striations on anterior and posterior margins; with 2 pairs of long and subequal posteroangular setae, 2–3 pairs of posteromarginal setae. Mesonotum with anterior campaniform sensilla, with median setae arising at middle, far from posterior margin. Metanotum with closely spaced striations, campaniform sensilla absent, median setae arising behind anterior margin ( Fig. 34 ). Mesofurca with spinula, metafurca without ( Fig. 35 ); metasternum with about 18–20 discal setae. Abdominal tergites V–VIII with paired ctenidia; I–VII posterior margin without well-developed dentate microtrichia; tergite VIII with complete comb ( Fig. 36 ); submedian and median setae on VIII sub-equal and short not extending beyond posterior margin; IX with 2 pairs of campaniform sensilla. Sternites with weak transverse striations, posterior margins without dentate craspedum, with 3 pairs of relatively long posteromarginal setae, median posteromarginal setae on segment VII arising in front.

Material studied. Malaysia, Selangor, Kajang. one female from Bambusa sp., 8.xi.2013 (NG, Y.F.); Terengganu, Kerteh, one female from Dendrocalamus asper (Poaceae) , 4.iii.2014 (Syarifah, Z.), one female from Gigantochloa albociliata (Poaceae) , 4.iii.2014 (Syarifah, Z.), in CISUKM and ANIC. Philippines, Luzon, Sipit Saburan, holotype female and 1 paratype female, on Bambusa sp., 20.vi.1987 (Reyes), in ANIC.

Comments. This species was described from The Philippines on 12 females collected with the holotype listed above, and is here newly recorded from Malaysia. The females are particularly similar in colour to S. biformis , the rice thrips, but have a mesothoracic spinula, and tergite IX bears two pairs of campaniform sensilla. The original description refers to a “few, weak, dentate microtrichia laterally” on the posterior margins of tergites VI and VII. Three such dentate microtrichia are clearly present on tergite VI (but not VII) of the paratype, however they are represented by insignificant craspedal lobes on both VI or VII in the holotype. As indicated by Mound (2011), there remains a possibility that spinalis is the same species as tenebricus from southern India, but the three original specimens of the latter species are not available. The three species of Stenchaetothrips treated above, that are here newly recorded from Peninsular Malaysia, bring the total members of this genus known from this country to seven ( Ng & Mound 2012).

Figures

FIGURES 31 – 36. Stenchaetothrips spinalis. (31) Head and pronotum; (32) Antenna; (33) Fore wing; (34) Mesonotum and metanotum; (35) Mesosternum and metasternum; (36) Abdominal tergites VI – IX.