Lagoenaxonopsalbia comorosensis Pešić & Smit, 2018

Pešić, Vladimir, Smit, Harry & Mary, Nathalie, 2018, Fifth contribution to the knowledge of water mites (Acari: Hydrachnidia) from the Comoros: a checklist and description of one new genus and four new species, Zootaxa 4483 (2), pp. 331-348 : 340

Lagoenaxonopsalbia comorosensis Pešić & Smit sp. nov.

( Figs. 6–8 )

Type material. Holotype male ( MNHN), dissected and slide mounted, Comoros, Mayotte, Hajangoua stream, upstream, 12°52'1,0"S, 45°10'25,7"E, alt. 265 m asl., 18-vii-2015, leg. Mary. Paratypes ( RMNH, MNHN): same data as holotype, 1/3/0; River Antanana, upstream, 12°57'55,7"S, 45°08'6,5"E, alt. 192 m asl., 30-vii-2014 0/1/0 (dissected and slide mounted); River Djalimou, upstream, 12°56'58,4"S, 45°07'23,7"E, alt. 165 m asl., 30-viii-2014 0/1/0 (dissected and slide mounted, MNHN); ibid., 16-vii-2015, 0/2/0 (0/1/0 dissected and slide mounted, RMNH).

Diagnosis. As given for genus.

Description. Male (holotype)—Dorsal and ventral shields fused posteriorly; dorsal shield L/W 450/328; excretory pore plate L/W 91/120, excretory pore flanked by numerous thin setae; ventral shield L/W 391/375; gnathosomal bay L 82; distance between projections associated with IV-L-insertions 198; width between the outer edges of the most lateral pair of acetabula 102. Ejaculatory complex with extremely elongated, straight posterior arms ( Fig. 6H ).

Palp: total L, dL/H, dL/H ratio: P-1, 20/16, 1.24; P-2, 47/30, 1.58; P-3, 27/25, 1.06; P-4, 61/23, 2.7; P-5, 26/10, 2.6; P-2/P-4 ratio 0.77; ventral margin of P-2 straight, without extension, P-4 not expanded ventrally, without heavy setae ( Figs. 6D–E ); gnathosoma vL 59.

Legs: dL of I-L: 34, 41, 47, 56, 70, 55; I-L-6 central H 22, I-L-6 dL/central H ratio 2.5; dL of IV-L: 69, 73, 92, 92, 91, 86; a few swimming setae, restricted to distal margins of penultimate leg segments; numbers: III-L-5, 1, IV- L-5, 2.

Female (from River Antanana, n = 1; in parentheses specimen from River Djalimou, n = 1)—Idiosoma L/W; dorsal shield L/W 447 (441)/344 (338), ratio 1.3 (1.31), Dgl-3 and -4 located close to each other; ventral shield L/ W 391 (384)/394 (372); gnathosomal bay L 92 (91), distance between IV-L-insertions 222 (211); posterior margin of the ventral shield irregular in shape, forming a large membranous genital bay with a longish gonopore; genital plates with postgenital gland flanked by two setae ( Figs. 8B–C arrows); width between outer edges of acetabular plates 152.

Palp: total L 195 (197); dL/H, dL/H ratio: P-1, 24/18-19, 1.27 (25/19, 1.33); P-2, 51/32, 1.59 (52/31, 1.66); P- 3, 29/25, 1.19 (29/25, 1.19); P-4, 62/19, 3.2 (62/19, 3.2); P-5, 29/12, 2.5 (29/11, 2.7); L P-2/P-4 ratio 0.83 (0.84); palp morphology as in male; gnathosoma vL 82 (92).

Legs: dL of I-L: 35 (30), 43 (37), 43 (44), 60 (59), 68 (69), 53 (54); I-L-6 central H (20), I-L-6 dL/central H ratio (2.7); dL of IV-L: 83, 66, 80, 88, 89, 84; swimming setae numbers: III-L-5, 2, IV-L-5, 2.

Etymology. Named after the archipelago ( Comoros) where the new species was found.

Distribution. Comoros ( Mayotte), known only from the loci typici.

Figures

FIGURE 6. Lagoenaxonopsalbia comorosensis sp. nov., male holotype, Hajangoua stream, Mayotte: A = dorsal; B = ventral; C = cauda, ventral view; D = gnathosoma and palp; E = palp; F = I-L; G = IV-L; H = ejaculatory complex. Scale bars = 100 µm.

FIGURE 7. Lagoenaxonopsalbia comorosensis sp. nov., female (A–C, F from River Antanana, D–E from River Djalimou, Mayotte): A = dorsal shield; B = ventral; C = genital field; D = gnathosoma and palp; D = palp (P-1 lacking); E = palp; F = gential plate region. Scale bars = 100 µm.

FIGURE 8. Lagoenaxonopsalbia comorosensis sp. nov., female (A, D, F specimen from River Antanana, B–C specimen from River Djalimou, Mayotte; A–C—photographs, D–F—line drawings): A = dorsal shield; B–C = acetabular plate (arrows indicating postgenital gland flanked by two setae); D = I-L; E = IV-L. Scale bars = 100 µm.