Reinstatement of Dermacentor kamshadalus Neumann (Acari: Ixodidae) as a valid species parasitizing mountain goats and sheep in the United States, Canada, and Russia

Abstract

Reexamination of Dermacentor albipictus (Packard, 1869) holdings stored in the United States National Tick Collection revealed several collections of a morphologically distinct Dermacentor species. Comparison of these specimens with other Dermacentor taxa showed that they are identical to an old taxon originally described as Dermacentor variegatus kamshadalus Neumann, 1908. For more than a century, this taxon was known only from the male holotype specimen collected in Russia, and the name was considered a junior synonym of D. albipictus. D. kamshadalus is reinstated here to a full species rank, and its male is redescribed and its female and nymph are described for the first time. Adults of D. kamshadalus can be distinguished from those of D. albipictus by a short spur on trochanters I, shorter spurs on coxae I, shorter dorsal cornua, more numerous perforations on spiracular plates, less numerous and shorter setae on idiosoma, especially around spiracular plates, and considerably paler coloration of the conscutum and scutum. The nymph of D. kamshadalus can be differentiated from that of D. albipictus by shorter spurs on coxae I and the numerous perforations on the spiracular plates. Adults and nymphs ofD. kamshadalus are recorded from the United States, Canada, and Russia, where they have been collected from mountain goats, Oreamnos americanus (de Blainville), bighorn sheep, Ovis canadensis Shaw, and sheep, Ovis sp. of which the species was not stated.

Fig. 1

Dermacentor kamshadalus, dorsally. (A) Male. (B) Female. (USA, MT, Ravalli Co., Blodgett Canyon, USNMENT00714658) Bar = 1 mm.

Fig. 2

Dermacentor kamshadalus and Dermacentor albipictus, variations in the coloration of male conscuta. (A–C) D. kamshadalus (USA, MT, Ravalli Co., Blodgett Canyon, USNMENT00714658). (D) D. kamshadalus (USA, CA, Sierra Nevada Mtns, Mt Baxter, USNMENT00714861). (E and F) D. albipictus (USA, MT, Ravalli Co., East Fork, USNMENT00714253). (G) D. albipictus (USA, MT, Granite Co., Maxville, USNMENT00714194). Bar = 1 mm.

Fig. 3

Dermacentor kamshadalus, male (USA, MT, Ravalli Co., Blodgett Canyon, USNMENT00714658). (A) Spiracular plate and circumspiracular setae. Bar = 0.2 mm. Arrows show orientation of spiracular plate (a—anterior; d—dorsal). (B) Gnathosoma dorsally. Bar = 0.2 mm. (C) Gnathosoma ventrally. Bar = 0.2 mm. (D) Coxae. Bar = 0.5 mm. (E) Coxa I. Bar = 0.2 mm. (F) Trochanter I. Bar = 0.2 mm.

Fig. 4

Dermacentor kamshadalus, female (USA, MT, Ravalli Co., Blodgett Canyon, USNMENT00714658). (A) Genital aperture. Bar = 0.1 mm. (B) Spiracular plate and circumspiracular setae. Bar = 0.2 mm. Arrows show orientation of spiracular plate (a—anterior; d—dorsal). (C) Gnathosoma dorsally. Bar = 0.2 mm. (D) Gnathosoma ventrally. Bar = 0.2 mm. (E) Coxae. Bar = 0.5 mm. (F) Coxa I. Bar = 0.2 mm. (G) Trochanter I. Bar = 0.2 mm.

Fig. 5

Dermacentor kamshadalus, nymph (Canada, British Columbia, Churn Creek, CNCI15280). (A) Scutum. Bar = 200 μm. (B) Setae of alloscutum. Bar = 20 μm. (C) Spiracular plate. Bar = 100 μm. Arrows show orientation of spiracular plate (a—anterior; d—dorsal). (D) Gnathosoma dorsally. Bar = 100 μm. (E) Gnathosoma ventrally. Bar = 100 μm. (F) Coxae. Bar = 100 μm.

Fig. 6

Dermacentor kamshadalus, map of geographical distribution. Star shows type locality (precise locality is unknown), filled circles show confirmed localities.

Fig. 7

Dermacentor albipictus, male, female (USA, MT, Ravalli Co., East Fork, USNMENT00714253), nymph (USA, MT, Ravalli Co., USNMENT00714103). (A) Male spiracular plate and circumspiracular setae. Bar = 0.2 mm. (B) Female spiracular plate and circumspiracular setae. Bar = 0.2 mm. (C) Nymphal spiracular plate. Bar = 100 μm. (D) Male gnathosoma dorsally. Bar = 0.2 mm. (E) Female gnathosoma dorsally. Bar = 0.2 mm. (F) Male coxa I. Bar = 0.2 mm. (G) Female coxa I. Bar = 0.2 mm. (H) Nymphal coxa I. Bar = 100 μm. (I) Male trochanter I. Bar = 0.1 mm. (J) Female trochanter I. Bar = 0.1 mm.