Canthyporus pallidus, Bilton, David T., 2015

Bilton, David T., 2015, A review of the Canthyporus exilis group, with the description of two new species (Coleoptera: Dytiscidae), Zootaxa 3957 (4), pp. 441-454 : 451

Canthyporus brincki Omer-Cooper

Still only known from the type locality, from Quthing in what is now Lesotho. I have re-examined the holotype, deposited in LUMZ, and illustrate the habitus and male genitalia here for comparison (see Figs. 1 & 2 ). The species is closest to C. nebulosus and C. pallidus sp. nov., and is best distinguished by a combination of colour pattern and male genitalia—see key below. In her description, Omer-Cooper (1965) states that the holotype was taken in locality 230 of the Swedish South African Expedition on 11/3/1951, which is listed as “Quthing, at light in the evening… 5600 ft.” in Brinck & Rudebeck (1955). A study of the label data of the holotype reveals instead that the specimen was taken at locality 234 on 15/3/1951, as noted by Biström & Nilsson (2006). As stated in Brinck & Rudebeck (1955), this locality contained a range of sampled habitats, including a forested stream, a stream flowing through a valley with steep rock walls, with a wet and shaded wall covered by algae. Given the habitat preferences of other members of the exilis group it seems likely that the specimen was obtained from one of these habitats.

Figures

FIGURE 1. Canthyporus exilis group, male habitus. A) C. aenigmaticus; B) C. brincki holotype; C) C. exilis; D) C. namaqualacrimus sp. nov. holotype; E) C. nebulosus; F) C. pallidus sp. nov. holotype. Scale bar = 1 mm.

FIGURE 2. Canthyporus exilis group, male genitalia (ventral and lateral view of median lobe of aedeagus, plus right paramere). A) C. aenigmaticus; B) C. brincki holotype; C) C. exilis; D) C. namaqualacrimus sp. nov. holotype; E) C. nebulosus; F) C. pallidus sp. nov. holotype. Scale bar = 0.25 mm.