Halacarus magniporus Krantz, 1973

Bartsch, Ilse, 2011, Halacarus socius (Acari: Halacaridae), description of the male and diagnoses of species of the Halacarus actenos group, Zootaxa 2800, pp. 18-40 : 32

Halacarus magniporus Krantz, 1973

Halacarus magniporus: Krantz (1973: 980, figs 17–23) .

Diagnosis. Length of female 825 µm, of male 550 µm. Frontal spine short, triangular, not extending beyond middle of P-2. Length of spine equalling 0.1 times that of AD and less 0.1 times that of idiosoma. Part of AD posterior to gland pores spiniform. Pair of glp-1 at 0.4. Pair of ds-1 anterior to glp-1. Pair of corneae in striated integument, OC absent. Pair of ds-5 immediately medial and adjacent to glp-4; setae ds-6 adjacent to glp-5. Anterior margin of GA broadly rounded; GA extending distinctly beyond margin of GO. Pair of pgs-1 level with posterior end of PE. Distance between anterior margin of GA and pair of pgs 0.9 times that between anterior margins of GA and GO. Male with 35–37 pairs of pgs arranged around GO.

Basal seta on P-2 at 0.7. P-3 with wide, boat-shaped spine. Telofemur, genu and tibia I with 2, 2, 4 spiniform ventral setae. Tarsi I and IV with two and three to four ventral setae, respectively. Paired claws of tarsi with accessory process.

Remarks. Distinctive characters of H. magniporus are the pairs of ds-4 and ds-5 adjacent (contiguous) to the gland pores and the wide, boat-shaped spine on P-3.

Distribution and ecology. Northeastern Pacific, Western coast of the United States (Oregon). From shallow water mussel beds.