Taxonomical, ecological and zoogeographical studies on anisitsiellid water mites (Acari: Hydrachnidia: Anisitsiellidae Koenike, 1910) from Madagascar Author Goldschmidt, Tom text Zootaxa 2008 2008-12-05 1954 1 1 120 https://biotaxa.org/Zootaxa/article/view/zootaxa.1954.1.1 journal article 10.11646/zootaxa.1954.1.1 1175­5334 5240917 Nilotonia ( Cookonia ) avomonina sp. nov. ( Figs 112–120 , Table 6 ) Type: Holotype female , MD 106 a, Ankaratra (Antananarivo), Reserve Manjakatompo, Mont Ambohimirandrana , spring area exposition south-east (drainage Rivière Mahiavona), upper spring, 2350 m asl , 13.4 °C, 2 µS/cm, 07.10.2001 , mounted. Habitat: Spring at 2350 m asl. Distribution: Madagascar (Central Highland – Ankaratra mountains). Derivatio nominis: Avo (Malagasy) — high; monina (Malagasy) — to live; referring to the high elevation (highest sample site within the water mite samples from Madagascar ) where the type locality (and only locality) is situated. Diagnosis: Characters of the genus; integument lined; caudal and lateral margins of Cx-IV widely extended; postgenital sclerite widely extended, separated from secondary extension of Cx-IV by very narrow stripe of soft integument; Vgl-2 and -4 individually on large platelets; Cx-I medially approximate but not fused, Cx-III medially with slight secondary sclerotization, approximate to each other; genital field elongated trapezoid, acetabula mid-sized, elongated-oval, touching each other; sub-terminal seta on leg-IV-6 relatively short, inserted far proximal, not reaching distal tip of segment; capitulum stout, nearly rectangular; palp relatively slender, P1 without dorsal seta, P4 ventrally with small protrusion, P5 slender. Description, female (n = 1): Idiosoma rounded-oval ( Fig. 112 ); dorsum mainly covered by large plate (L/ W 775/544), including Dgl-3 to -6, Lgl-4 and post-ocular setae, colour slightly dark-purple; lateral eyes small, oval, separated on both sides, lying free under integument; Dgl-1 far anterior; soft integument around dorsal plate lined, bearing slightly extended Dgl-2, Lgl-2 and l1-4; setae of Dgl-1, -3, -4 and -5 mid-sized, setae of other glandularia small ( Fig. 113 ); Lgl-1 fused with lateral secondary sclerotization of Cx-IV; Lgl-3 and l 5 in soft integument on ventral side, secondary sclerotization of Cx-IV forming a nearly closed, rounded ventral shield (L/W 706/755), extended also latero-dorsally of the Cx-I/II/III; Cx-I medially approximate, posterior half overlapping, but separated, postero-lateral margin of Cx-II lying over Cx-III, postero-medial margin of Cx-II lying under Cx-III; Cx-III medially approximate, medial margin of Cx-III extended by fine secondary sclerotization; suture line between Cx-III and Cx-IV incomplete, medially curved towards anterior, medial margin of Cx-IV straight to slightly concave, forming very narrow genital bay, caudal margin short, rounded, latero-caudal margin oblique towards anterior, insertion of leg-IV far anterior ( Fig. 112 ); medial and caudal margin of Cx-IV clearly visible, lateral margin unclear; setae at postero-lateral margin of Cx-I and medial margin of Cx-III/IV very small ( Fig. 112 ); genital bay narrow, approximate to genital field, formed by medial margins and caudal secondary sclerotization of Cx-IV as well as post-genital sclerite; genital flaps elongated, anteriorly and postero-laterally smoothly rounded, laterally nearly straight, broadened towards cauda; acetabula mid-sized, elongated-oval, slender, touching each other, Ac1 distant from anterior margin of genital flaps, Ac3 slightly distant from posterior margin; pre-genital sclerite triangular, laterally protruding genital flaps, post-genital sclerite large, greatly extended by secondary sclerotization, including setae of Vgl-1, forming caudal segment of ventral shield ( Fig. 112 ); Vgl-3 very close to caudal margin of Cx-IV, included in secondary sclerotization of Cx-IV; Vgl-2 and Vgl-4 on relatively large, irregular platelets; excretory pore without sclerotization ( Fig. 112 ); legs with several large setae; claws on leg-I to -III with one small dorsal and one larger ventral clawlet ( Figs 114, 115 ), leg-IV-6 distally tapering, with two small, peg-like terminal setae ( Fig. 116 ); capitulum very short, relatively high, dorsal and ventral margins nearly parallel ( Fig. 117 ); chelicera strong, proximally high, claw very heavy, dorso-distally serrate ( Figs 118, 119 ); palps slender, P1 without setae, P2 with one latero-ventral seta and six dorsal setae, ventral margin straight, P3 with one lateral and three dorsal setae, P4 distally curved, dorso-distal corner rounded, ventral setae slightly in distal half, ventral margin with slight protrusion, P5 slender, cone-shaped with long slender terminal claws ( Figs 117, 120 ). FIGURES 112–120. Nilotonia ( Cookonia ) avomonina subgen. et sp. nov. , female holotype (MD 106a): 112, idiosoma, ventral view; 113, idiosoma, dorsal view; 114, leg-II; 115, leg-III-6; 116, leg-IV (first segment broken); 117, capitulum with left palp, lateral view; 118, left chelicera, lateral view; 119, right chelicera, medial view; 120, right palp, medial view. Scale bars = 100 µm. FIGURES 121, 122. Mamersella (Neomamersella) tototaensis Cook, 1966 , female holotype (FMC Lib 82): 121, leg-II; 122, leg-IV. Scale bar = 100 µm. Male: Unknown Remarks: The two species of Cookonia are separated by the degree of fusion of their ventral shield (postgenital plate and Cx-IV fused in N. ( Cookonia ) anjozorobe , not fused in N. ( Cookonia ) avomonina ), the extent of the female dorsal plate (in N. ( Cookonia ) anjozorobe not including Dgl-6 and Lgl-4) and proportions of the palps and legs (slenderer in N. ( Cookonia ) avomonina ). A sexual dimorphism similar to N. ( Cookonia ) anjozorobe in the extent of the ventral shield (larger in male) is found in Bharatonia Cook, 1967 from India .