Nilotonia (Telotaolana) hodivaventy, Goldschmidt, 2008

Goldschmidt, Tom, 2008, Taxonomical, ecological and zoogeographical studies on anisitsiellid water mites (Acari: Hydrachnidia: Anisitsiellidae Koenike, 1910) from Madagascar, Zootaxa 1954 (1), pp. 1-120 : 35-38

Nilotonia (Telotaolana) hodivaventy sp. nov.

( Figs 56–70 , Table 4)

Type series: Holotype male, MD 71 a, Andohahela (Tulear), Isaka, spring area south pass RIP 118 (km 36), 700 m asl, 16.0–18.4 °C, 55–60 µS/cm, 10.09.2001, mounted; paratype, same locality and date, 0/1/0 mounted.

Habitat: Spring at 700 m asl.

Distribution: Madagascar (Southern mountain region).

Derivatio nominis: Hodi (Malagasy) — crust, vaventy (Malagasy) — thick, referring to the heavy dorsal and ventral armour characterising the species.

Diagnosis: Idiosoma small, oval; dorsal plates approximate in both sexes, Dgl-2 to -4 fused with anterior plates in males; integument coarsely lined; sexual-dimorphism in sclerotization of venter: Male with unified ventral shield, female with very large secondary sclerotization still separated between post-genital sclerite and Cx-IV; Cx-II/III medially fused in male; genital field oval pear-shaped, acetabula elongated-oval, touching each other; legs strong, relatively compact, leg-IV bearing several long, heavy setae; claws on leg-I to -III with small ventral clawlet in males, without in females, in both sexes with very tiny dorsal clawlets; leg-IV with relatively long sub-terminal seta in males, shorter in females; capitulum short, compact, rostrum short, pointed; palp compact.

Description, male (n = 1): Idiosoma oval, pear-shaped ( Fig. 56 ); dorsum mainly covered by three large, pale greyish-purple plates, nearly touching each other; posterior plate rounded, anteriorly pointed (L/W 363/ 324), including (far laterally) Dgl-5, -6 and Lgl-4, anterior plates oblique elongated-rhombic (L/W 216/113), bearing post-ocular setae, fused with Dgl-2 to -4; eyes small, oval, separated on both sides, lying free under the integument ( Fig. 57 ); Dgl-1, pre-ocular setae and three platelets (central elongated, shown in Fig. 57 ) frontally between dorsum and venter; soft integument between dorsal plates and ventral shield coarsely lined; Lgl- 1, -2 and lyrifissures in soft integument between dorsum and venter, Lgl-3 fused with ventral shield; Cx-I medially long, very closely approached, caudally fused with antero-medial corners of Cx-III and caudal margin of Cx-II; medial margins of Cx-III nearly touching each other; Cxgl-2 between Cx-II and Cx-III, Cxgl-4 at anterior margin of Cx-III ( Fig. 56 ); medial margin of Cx-IV fused with ventral shield, not visible, forming very narrow genital bay, caudal margin with hook-shaped protrusion, latero-caudally oblique; Vgl-3 close to latero-caudal margin of Cx-IV; pre- and post-genital sclerites completely fused with ventral shield; Vgl-2 and -4 on large platelets, directly caudal to ventral shield (partly under soft integument) ( Fig. 56 ); genital field oval pear-shaped, anteriorly tapering, anteriorly and posteriorly smoothly rounded; acetabula mid-sized, elongated-oval, touching each other, Ac1 and Ac3 slightly distant from anterior and posterior margins of genital flaps; setae of Vgl-1 posterior medio-caudal margin of Cx-IV ( Fig. 56 ); excretory pore without sclerotization ( Fig. 56 ); genital skeleton compact, brachia distalia oblique, brachia proximalia strong, broad, oriented proximally ( Fig. 58 ); legs strong, compact, bearing many large and heavy setae; claws on leg-I to -III slender with small ventral and very tiny dorsal clawlet, leg-II-5 and -6 ventrally and distally with many tiny hair-like setae ( Fig. 59 ), leg-IV-3 to -5 short, compact, mainly distally with many heavy setae, leg-IV-6 distally tapering, subterminal seta relatively long ( Figs 60, 61 ); capitulum compact with short, pointed rostrum ( Fig. 62 ), palps compact, P1 with one dorsal seta, P2 short, ventro-lateral seta on little hump, five dorsal setae, P3 with one lateral and three dorsal setae, P4 compact, distally relatively high, ventral setae on flat protrusions, P5 compact ( Figs 62, 63 ).

Female (n = 1): Secondary sclerotization of idiosoma generally weaker than in male ( Fig. 64 ); dorsal plates not fused with glandularia, posterior dorsal plate more oval (L/W 441/348); Dgl-2 to -6 and Lgl-4 on mid-sized platelets, closely approached to dorsal plates, two pairs of small platelets anterior Dgl-3, lateral Dgl-2 ( Fig. 65 ); general shape of coxal field and genital field as in male; Cx-IV more elongated, Cx-III/IV as well as post-genital plate with extended secondary sclerotization, not fused to ventral shield, integument between coxae, genital field, pre- and post-genital plate granular, not lined ( Fig. 64 ); medial margin of Cx-IV concave, Cx-IV mainly caudally and laterally extended by secondary sclerotization (lateral extension reaching far towards anterior); pre-genital sclerite broad triangular, post-genital sclerite very extended, on one side including seta of Vgl-1; Vgl-2,-4 and Lgl-3 on irregular, mid-sized platelets, one pair of mid-sized (very different size between left and right) postero-ventral platelets lateral to post-genital plate ( Fig. 64 ); legs as in males, less compact ( Figs 66, 67 ); gnathosoma as in males, less compact ( Figs 68-70 ).

Remarks: The two species Nilotonia (Telotaolana) ankaratra and Nilotonia (Telotaolana) hodivaventy display a striking sexual dimorphism in the degree of secondary sclerotization. Such a degree of dimorphism has not been described in other species of Nilotonia yet, but a weaker sclerotization in the female is also found in Nilotonia (Telotaolana) longipalpis sp. nov. (see below) and in Nilotonia violacea . Nilotonia (Telotaolana) ankaratra differs from N. (Telotaolana) hodivaventy in a weaker secondary sclerotization, including less glandularia and leg-IV bearing heavier setae in denser rows. A similarly developed male ventral shield is found in Nilotonia (s. str.) cooki Panesar, 2004; however, the latter is differentiated from the new species from Madagascar in the following characters: Cxgl-4 near suture between Cx-III and Cx-IV, dorsum without extended secondary sclerotization, leg-III and -IV with swimming hairs.

Figures

FIGURES 56–63. Nilotonia (Telotaolana) hodivaventy subgen. et sp. nov., male holotype (MD 71a): 56, idiosoma, ventral view; 57, idiosoma, dorsal view; 58, genital skeleton, anterior view; 59, leg-II; 60, leg-IV (sub-terminal seta on leg- IV-6 broken); 61, leg-IV-6, posterior view; 62, capitulum with left palp and chelicera, lateral view; 63, right palp, medial view. Scale bars = 100 µm.

FIGURES 64–70. Nilotonia (Telotaolana) hodivaventy subgen. et sp. nov., female paratype (MD 71a): 64, idiosoma, ventral view; 65, idiosoma, dorsal view; 66, leg-II; 67, leg-IV-2 to -6; 68, capitulum with left palp, lateral view; 69, right palp, medial view; 70, left chelicera, lateral view. Scale bars = 100 µm.