Bacillothrips nobilisBacillothrips nobilisFemale fully winged, but both sexes also micropterous. Body, legs and antennae brown to dark brown, tarsi paler; antennal segments III–V bicoloured, yellow with apices brown; fore wings pale; major setae pale to light brown. Antennae 8-segmented, segment III with 2 slender sense cones, IV with 4 similar sense cones; VIII with narrow pedicel. Head elongate, cheeks sinuate, narrowed behind eyes; cheeks with one pair of short stout setae behind eyes; one pair of long setae on anterior margins of ocellar triangle, 3 pairs of shorter setae on vertex (postocellar, postocular and midvertex); maxillary stylets about one fifth of head width apart, not retracted as far as postocular setae. Pronotum weakly reticulate, with no epimeral sutures; epimeral setae long with apices broadly blunt, remaining major setae shorter; prosternal basantra present, mesopresternum transverse. Fore tarsus with no tooth. Fore wing parallel sided. First abdominal segment, pelta, transverse but with lateral wings separated from median lobe as a pair of triangular sclerites; tube long with setae along lateral margins.
Male with no fore tarsal tooth; abdominal tergite VI laterally with paired drepanae extending beyond segment VII; segment VIII laterally with pair of prominent tubercles; tube constricted in basal third, lateral margins with setae.
The genus Bacillothrips comprises three species, all from Europe. It is distinguished from Megalothrips by the form of the pelta (first abdominal tergite), and the less deeply retracted and slightly more widely spaced maxillary stylets. However, the distinction between these two genera and the genus Megathrips remains less than satisfactory. Together with the tropical species-rich genus Bactrothrips it seems likely that they form a single clade, within which recognition of smaller genera lacks phylogenetic significance (Mound & Palmer, 1983). B. nobilis is the largest species of thrips found in Britain with a total body length of 4.0-7.0 mm.
Feeding on the spores of unidentified fungi, and breeding on dead branches of Salix [Salicaceae], although also taken in leaf litter.
Recorded four times in Britain, including the type population at Wicken Fen, Cambridgeshire (Bagnall, 1909b); also, a population taken at Garve, Highland, in Scotland, in 1949 (Mound et al., 1976), a single female from Berkshire in 1998 (Verdcourt, 1999), and a single male from Wood Walton Fen, Cambridgeshire in 2012. Recorded sporadically across Europe, as far north as Norway (Kobro, 2011) and as far south as Spain.
PHLAEOTHRIPIDAE - IDOLOTHRIPINAE
Bacillothrips nobilis (Bagnall)
Megathrips nobilis Bagnall, 1909: 130
Bagnall RS (1909b) Notes on Thysanoptera (Tubulifera) new to the British fauna, with description of a new species of Megathrips. Entomologist’s Monthly Magazine 45: 129–132.
Kobro S (2011) Checklist of Nordic Thysanoptera. Norwegian Journal of Entomology 58: 20–26.
Mound LA, Morison GD, Pitkin BR & Palmer JM (1976) Thysanoptera. Handbooks for the Identification of British Insects 1 (11): 1–79.
Mound LA & Palmer JM (1983) The generic and tribal classification of spore-feeding Thysanoptera (Phlaeothripidae: Idolothripinae). Bulletin of the British Museum (Natural History). Entomology 46: 1–174.
Verdcourt B (1999) Megathrips nobilis Bagnall (Thysanoptera, Phlaeothripidae) in East Berkshire. Entomologist’s Monthly Magazine 135: 87.
