Biltothrips Bhatti

Y. F. Ng & L. A. Mound, 2016, Two new species of Scirtothrips genus-group (Thripidae) of Northern Peninsular Malaysia, Zootaxa 4088 (1), pp. 141-145 : 141-142

Biltothrips Bhatti

Type species Sericothrips minutus Bhatti 1967 .

Previously known from a single species, this genus was considered remarkable within the Scirtothrips genus-group for the lack of the first pair of ocellar setae (Ng & Mound 2015). However, this pair of setae is present in the new species described below. Despite this, the two species share the autapomorphic state of tergal setal pair S1 being far apart and closer to setal pair S2 than to each other, particularly on abdominal tergites VII and VIII ( Figs 4, 5 ). The two species are also unusual, although not unique within the Scirtothrips genus-group, in having a complete posteromarginal microtrichial comb on tergite VII and VIII ( Fig. 5 ).

Diagnosis. Female macropterous. Head wider than long; mouth-cone short, rounded at apex, with 3-segmented maxillary palpi; ocellar setae I present or absent, pair III variable in position, four pairs of postocular setae ( Fig. 1 ). Antennae 8-segmented, segment I without dorso-apical setae, III and IV with forked sense cone. Pronotum transversely striate, with no long setae; mesonotum with median setae far from posterior margin; metascutum with two pairs of setae at anterior margin; basantra degenerate with no setae; ferna not joining medially; meso and metafurca with spinula. Fore wing first vein with few widely spaced setae on distal half, second vein with or without a few setae, posteromarginal cilia not undulated ( Fig. 6 ).Tarsi 2-segmented. Abdominal tergites II–VIII with closely spaced rows of microtrichia on lateral thirds; setal pair S1 wide apart and closer to setae S2 than to each other, S1 small on at least II–IV, on VII–VIII equally long; VII–VIII with a complete posteromarginal comb ( Fig. 5 ); tergite IX without discal microtrichia, with one pair of mid-dorsal setae but no CPS. Sternal microtrichia rows variable in extent; II–VII with posteromarginal microtrichia comb present laterally; II with 2 pairs of posteromarginal setae, III–VII with 3 pairs ( Fig. 7 ). Male of B. minutus similar to female, with no drepanae on tergite IX, and no sternal pore plates.

Key to species of Biltothrips

1. Ocellar setae pair I absent, pair III arise within the triangle; head with numerous transverse striae in ocellar area; tergites IV–VI with setal pair I sub-equal in size to pair II, and arising laterally to CPS; sternites III–VI with many rows of microtrichia medially; fore wing second vein without setae ....................................................................................................................................... minutus -. Ocellar setae pair I present, pair III arise outside the triangle ( Fig. 1 ); head without sculpture in ocellar area; tergites IV–VI with setal pair I much smaller than pair II, and arising mesad of CPS ( Fig. 4 ); sternites with microtrichial rows only laterally ( Fig. 7 ); fore wing second vein with 3 setae ............................................................................................................................ perakensis sp.n.

Figures

FIGURES 1 – 8. Biltothrips perakensis sp. n: (1) Head; (2) Pteronota; (3) Antennal segments I − VIII; (4) Abdominal tergites III – VI; (5) Abdominal tergites VI – X; (6) Fore wing; (7) Sternites IV – VII; (8) Meso- and metasterna.