Pontarachna africana, Smit, 2002

Smit, Harry, 2002, Two new species of the water mite family Pontarachnidae (Acari: Hydrachnidia), with a discussion of the taxonomic status of Pontarachna hinumaensis Imamura, Zootaxa 22, pp. 1-8 : 3-4

Pontarachna africana n. sp.

Figs. 1­3

Material examined

Holotype, female: Gansbaai , 100 km Southeast of Cape Town, South Africa, 28 November 2000, leg. D. Marshall & S. Proches ( ZMAN) . Paratype: 1 female, same data as holotype ( ZMAN) .

Diagnosis

In females the shape of the pre­ and postgenital sclerites in combination with the configuration of the wheel­like acetabula are diagnostic for the new species. Male unknown.

1 Description

Female: body soft, 510 (526) long and 445 (421) wide. First coxal plates separated medially. Suture line of second and third coxal plates incomplete, suture line of third and fourth coxal complete and ending in apodemes. Both lateral and medial posterior apodemes of fourth coxal plates short. Pregenital sclerite slightly bowed, postgenital sclerite almost straight, 46 and 52 wide respectively. Pregenital sclerite located between medial posterior apodemes of fourth coxal plates. Postgenital sclerite with a pair of wheel­like acetabula sensu Cook (1996). Posteriorly of genital field two pairs of wheel­like acetabula (see arrows). Posteriorly of fourth coxal plates a large glandularium­like structure. Lengths of PI­PV: 20, 58, 56, 82, 22; ventral margin of PIV straight. Lengths of I­leg­4­6: 60, 80, 82. Lengths of IV­leg­4­6: 108, 130, 122; IV­leg­5 with two swimming setae.

Male: Unknown.

Remarks

Similar species are Pontarachna valkanovi and P. pacifica , which have more or less similarly shaped (although much narrower) pre­ and postgenital sclerites. However, the configuration of the wheel­like acetabula of valkanovi and pacifica is different compared to the new species, while PIV of these species is more bowed.

Figures

FIGURES 1 ­ 3. Pontarachna africana n. sp., holotype female. 1, ventral view; 2, palp + capitulum; 3, I­leg­ 4 ­ 6. Scale bar 50 Pm.