Orthotrichia becca, Wells, Alice & Dostine, Peter, 2016

Wells, Alice & Dostine, Peter, 2016, New and newly recorded micro-caddisfly species (Insecta: Trichoptera: Hydroptilidae) from Australia’s north, including islands of Torres Strait, Zootaxa 4127 (3), pp. 591-600 : 597

Orthotrichia becca sp. nov.

Figures 16, 17

Diagnosis. In having a pair of strong, stout black setae on abdominal segment VIII, this species is also a member of the Orthotrichia gracilis Group. In O. becca the bases of the 2 setae are very close together, resembling those of the northern Australian Orthotrichia bellicosa Wells. However , O. becca differs from that species in having closepressed, distally cone-shaped gonopods with their extremities heavily sclerotised, and, distally on the dorsum of the dorsal plate, a lightly sclerotised beak-shaped structure.

Description. Male. Length of each forewing 1.3–1.5 mm (n = 2). Antennae each with 24 antennomeres. Genitalia as in Figs 15, 16 . Abdominal segment VIII bearing dorso-mesally one pair of closely based stout, elongate black spines; dorsal plate with sinuous blade-like sclerotised spine on left side, with membranous beaklike structure beyond it; on right broad straight spine; paramere long, slender spine; gonopods almond-shaped, distally sclerotised, close-pressed; dorsal process short, quadrate, membranous; antero-ventral apodeme elongate; phallic apparatus as for genus, slender in distal section, with a spiral titillator.

Female. Unknown.

Types. Holotype. male, NORTHERN TERRITORY, Berry Springs, 11–12.i.2016, P. Dostine, light trap (NTM, slide). Paratype. 1 male, data as for holotype (ANIC, slide).

Etymology. From the Latin for beak — beccus, for the beak-like structure on the dorsal plate.

Remarks. The similarity in male genitalia of this species and O. bellicosa , described from NW Western Australia, possibly has led to earlier misidentifications of other Northern Territory specimens.

Figures

FIGURES 14 – 20. Orthotrichia spp. 14, 15, Orthotrichia pethericki sp. nov., male genitalia: 14, ventral; 15, dorsal. 16, 17, Orthotrichia becca sp. nov., male genitalia: 16, ventral; 17, dorsal. 18, Orthotrichia ensiformis Wells, male genitalia, ventral. 19, 20, Orthotrichia turrita Wells, male genitalia: 19, phallic apparatus; 20, ventral. Abbreviations: VIII, IX = abdominal segments VIII and IX; dpl = dorsal plate; dpr = dorsal process of gonopods; gon = gonopod; l dsp = left dorsal spine on dorsal plate; ph = phallic apparatus; pr = paramere; r dsp = right dorsal spine on dorsal plate; st s = stout setae on segment VIII; tlr = titillator.