Torrenticola anomallela Cook, 1966

Pešić, Vladimir & Smit, Harry, 2014, Torrenticolid water mites (Acari: Hydrachnidia: Torrenticolidae) from Ghana, Zootaxa 3820 (1), pp. 1-80 : 5

Torrenticola anomallela Cook, 1966

( Figs. 1A–D , 2A–C , 12A–B , 14A–B )

Torrenticola anomallela Cook 1966: 64 .

New records. Ghana: Apkonu stream, downstream of falls, Logba Tota, 6º 53.054 N, 0º 28.024 E, alt. 362 m asl., 21.ii.2013, Smit, 0/1/0 (mounted); Akaa Falls, 6º 10.516 N, 0º 11.723 E, 9.iii.2011, Smit, 2/1/0 (1/0/0 mounted); Supon stream near Asiakwa, Atewa Hills, 6º 15.530 N, 0º 30.642 W, alt. 250 m asl., 7.iii.2011, Smit, 0/1/0 (mounted).

Morphology. General features —Idiosoma roundish; Cxgl–4 subapical, only slightly posterior of Cx-I tips; posterior suture lines of Cx-IV extending back beyond posterior margin of genital field; excretory pore and Vgl–2 clearly posterior to the line of primary sclerotization, excretory pore slightly posterior ( Fig. 1B ), or on the level with Vgl–2 (ventral view: Fig. 2A , 14A ) ( Fig. 2A ); gnathosomal rostrum long, ventral margin in lateral view sharply curved ( Fig. 1D ); P-2 shorter than P-4, P-2 with a long and slender, anteriorly directed ventrodistal projection; P-3 ventrodistal protrusion shorter, cone shaped; P-4 slender, with well developed ventral protuberances, ending in two tips separated by a concavity and bearing one very long and three short setae ( Figs. 1C , 2B ). Male: genital field subrectangular in shape; ejaculatory complex normal in shape (proximal and distal arms and proximal chamber well developed, Fig. 2C ). Female: genital field pentagonal in shape, anteriorly enlarged and strongly tapering posteriorly.

Measurements. Male (from Akaa Falls, n = 1)—Idiosoma (ventral view: Figs. 2A , 14A ) L 534, W 355; dorsal shield ( Fig. 12A ) L 406, W 309, L/W ratio 1.31; dorsal plate L 369; shoulder platelets L 113–116, W 47, L/W ratio 2.4–2.5; frontal platelets L 116–119, W 48–52, L/W ratio 2.2–2.5; shoulder/frontal platelets L ratio 0.96–1.0. Gnathosomal bay L 116, Cx-I total L 203, Cx-I mL 117, Cx-II+III mL 91; ratio Cx-I L/Cx-II+III mL 2.2; Cx-I mL/ Cx-II+III mL 1.29. Genital field L/W 107/89, ratio 1.2; ejaculatory complex L 154; distance genital field-excretory pore 84, genital field-caudal idiosoma margin 133. Gnathosoma vL 243; chelicera total L 280; palp total L 263, dL/ H, dL/H ratio: P-1, 32/26, 1.23; P-2, 72/41, 1.77; P-3, 55/38, 1.47; P-4, 88/23, 3.8; P-5, 16/10, 1.6; P-2/P-4 ratio 0.82; dL of I-L-2–6: 53, 59, 68, 84, 83; I-L-6 H 28, dL/H I-L-6 ratio 3.0.

Female (from Apkonu stream, n =1)—Idiosoma (ventral view: Figs. 1B , 14B ) L 595, W 397; dorsal shield ( Fig. 1A , 12B ) L 450, W 350, L/W ratio 1.29; dorsal plate L 413; shoulder platelets L 122–128, W 48–49, L/W ratio 2.5–2.65; frontal platelets L 116–119, W 47–50, L/W ratio 2.3–2.53; shoulder/frontal platelets L ratio 1.03–1.1. Gnathosomal bay L 116, Cx-I total L 213, Cx-I mL 97, Cx-II+III mL 62; ratio Cx-I L/Cx-II+III mL 3.44; Cx-I mL/Cx-II+III mL 1.57. Genital field L/W 109/109, ratio 1.0; distance genital field-excretory pore 147, genital field-caudal idiosoma margin 209. Gnathosoma vL 286; chelicera total L 328; palp total L 287–288, dL/H, dL/H ratio: P-1, 31/25–26, 1.2; P-2, 83/49, 1.69; P-3, 74/46, 1.61; P-4, 90/25, 3.66; P-5, 15/9, 1.7; P-2/P-4 ratio 0.92; dL of I-L-2–6: 54, 65, 75, 89, 82; I-L-4–6 H 25, dL/H I-L-4–6 ratio 3.24.

Remarks. The specimens from Ghana match the general morphology of Torrenticola anomallela , a species described by Cook (1966) from Liberia. However, as the idiosoma and palp of the female is not illustrated in the original description, differences can be observed only in comparison with illustrations of the male. In the male type specimen the ventrodistal projection of P-2 is more pointed, instead of finger-shaped in the specimens from our study. Furthermore, Cook (1966) stated that the gnathosoma is similar as illustrated for Torrenticola motasi , with the ventral margin only slightly curved. Thus, our assignment of the specimens from Ghana is tentative, and only with more material in the future will it be possible to decide whether this is really just a variable species or a complex of several similar species.

Distribution. Liberia ( Cook 1966); Congo ( Zaire) ( K.O. Viets & Böttger 1974), Ghana (first record).

Figures

FIGURE 1 A – D. Torrenticola anomallela Cook, 1966, female, Apkonu stream: A = dorsal shield; B = idiosoma, ventral view; C = palp, medial view; D = gnathosoma. Scale bars = 100 Μm.

FIGURE 2 A – C. Torrenticola anomallela Cook, 1966, male, Akaa Falls: A = idiosoma, ventral view; B = palp, medial view; C = ejaculatory complex. Scale bars = 100 Μm.

FIGURE 12 A – I. Photographs of dorsal shield: A – B Torrenticola anomallela Cook, 1966: A = male from Akaa Falls, B = female from Apkonu stream. C – D Torrenticola bomiensis Cook, 1966: C = male from Supon stream, D = female from Tagbo river. E – F Torrenticola fasciata (K. Viets, 1916), unnamed creek crossing road to Ankasa NP: E—male, F—female. G – H Torrenticola motasi Cook, 1966: G = female from tributary of Oguntwe, H = male from stream downstream of Wanjakli Falls. I Neoatractides erato n. sp., holotype male, upstream Sagyimase.

FIGURE 14 A – I. Photographs of ventral shield: A – B Torrenticola anomallela Cook, 1966: A = male from Akaa Falls, B = female from Apkonu stream. C – D Torrenticola bomiensis Cook, 1966: C = male from Supon stream, D = female from Tagbo river. E – F Torrenticola fasciata (K. Viets, 1916), unnamed creek crossing road to Ankasa NP: E = male, F = female. G – H Torrenticola motasi Cook, 1966: G = male from stream downstream of Wanjakli River, H = female from tributary of Oguntwe. I Neoatractides erato n. sp., holotype male, upstream Sagyimase.