Teratothyas (Ascoteratothyas) levigata, Gerecke, 2020

Gerecke, Reinhard, 2020, The early derivative water mites (Acari: Hydrachnidia, superfamilies Eylaoidea, Hydrachnoidea and Hydryphantoidea) of Madagascar, Zootaxa 4727 (1), pp. 1-77 : 54-55

Teratothyas (Ascoteratothyas) levigata sp. nov.

Fig. 26 a–g

Type series: Holotype ♂, MNHN Ac 1448, MD 069b, 09.09.2001 Andohahela ( Tulear ), Isaka , W stream at the S National Park border (W RIP 118 ), 200 m, pool, in liquid, together with paratype ♀ . Paratypes: Same site and date, (1/2/1 pn) slide mounted, Ac 1376-1378; MD 069a, 09.09.2001 Andohahela ( Tulear ), Isaka , W stream at the S National Park border (W RIP 118 ), 200 m, riffle, (2/0/0) slide mounted, Ac 1379-1380; MD 070a, 09.09.2001 Andohahela ( Tulear ), Isaka , E stream at the S National Park border (W RIP 118 ), 200 m, riffle, (2/0/0) slide mounted, Ac 1381; (1/0/0) in liquid, Ac 1449; MD 070b, 09.09.2001 Andohahela ( Tulear ), Isaka , E stream at the S National Park border (W RIP 118 ), 200 m, pool, (0/1/0) in liquid, Ac 1450.

Diagnosis: Membranous integument areas smooth or with fine striation. Genital field ( Fig. 26 b ) with large acetabula (L Ac-1, 60–67, 36–39 % genital field L, Ac-2, 65–78, 41–43 %). Palp ( Fig. 26 e ) short and stout (total L, P-4 L ♂♂, 211–231, 77–83; ♀♀, 269, 100), maximum H P- 4 in basal part.

Description: Membranous integument areas smooth or with a very fine striation visible only in tangential view. Dorsocentral plates with a dense fine porosity of (15–20 pores/transect), ventral plates and secondary sclerite strips with large pores distinctly set off from each other. Genital field with large acetabula (Ac-1 nearly as long as posterior medial plate margin, posterior end on level of anterior end of Ac-2; L Ac-1, 60–67, 36–39 % genital field L, Ac-2, 65–78, 41–43 %). Genital flaps together forming a circle, anterolaterally with porose secondary sclerite, anteromedially concave, embracing the longish Ac-1. Plates posterolaterally embracing genital field with a strong, pore-free anterior margin. Leg claws with an obtuse angled ventral blade.

Gnathosoma ( Fig. 26 d ) slender, ventral margin in proximal part straight, on the level of palp insertion forming an obtuse angle, distal part concave. Chelicera ( Fig. 26 c ) L/H 9.5–12.1. Palp ( Fig. 26 e ) with P-4 relatively short, maximum H proximally, not remarkably narrowed from the base to distal third.

Measurements: Male: Idiosoma L/W 1050–1230/730–784; coxal field L/W 550–616/580–650; Cx-I+II L/W 302–360/215–280; Cx-III+IV L/W 350–404/290–325; genital field L/W 160–171/165–200; maximum diameter Ac-1, 60–67, Ac-2, 65–72 Ac-3, 49–56, ejaculatory complex L 165; gnathosoma L 305–323; chelicera total L 346– 382, L/H 9.4–11.6; basal segment/claw 1.08–1.14. Palp total L 211–231; L, L/H ratio, relative L [% total L] palp segments: P-1, 30–36, 0.63–1.06, 14–16; P-2, 49–54, 1.44–1.75, 23–24; P-3, 25–30, 0.81–0.97, 11–14; P-4, 77–83, 2.85–3.32, 35–37; P-5, 26–33, 2.10–2.75, 12–14; L ratio P-2/-3, 1.75–2.16, P-2/-4, 0.64–0.67, P-3/-4, 0.30–0.38. Leg segments L/H, L/H ratio: I-L-2, 90–100, 1.64–1.82; I-L-3, 97–105, 1.74–1.91; I-L-4, 153–175, 3.05–3.50; I- L-5, 160–185, 3.40–3.78; I-L-6, 149–175, 2.92–3.30; claw L 45–55. II-L-2, 108–115, 1.88–2.15; II-L-3, 113–120, 1.92–2.30; II-L-4, 191–210, 3.70–4.20; II-L-5, 195–220, 4.10–4.40; II-L-6, 167–210, 3.50–4.11; claw L 40–50. III-L-2, 85–92, 1.70–1.86; III-L-3, 92–105, 1.95–2.10; III-L-4, 175–190, 3.80–3.90; III-L-5, 175–200, 4.33–5.00; III-L-6, 169–195, 3.25–3.58; claw L 43–55. IV-L-2, 115–125, 2.19–2.27; IV-L-3, 122–140, 2.35–2.55; IV-L-4, 225–250, 4.55–4.74; IV-L-5, 221–245, 4.90–5.44; IV-L-6, 196–220, 3.78–4.00; claw L 50–60. Total L segments 2–6: I-L, 648–740; II-L, 781–875; III-L, 704–775; IV-L, 885–980.

Females: Idiosoma L/W 1310–1500/1000–1080; coxal field L/W 640–740/760–84; Cx-I+II L/W 425–450/265– 290; Cx-III+IV L/W 410–490/380–410; genital field L/W 185–195/200–240; maximum diameter Ac-1, 65–76, Ac-2, 78–90, Ac-3, 55–63; gnathosoma L 350–370; chelicera total L 442–485, basal segment/claw 1.10–1.20, L/H 11.1–12.1; Palp total L 269; L, L/H ratio, relative L [% total L] palp segments: P-1, 35, 0.82, 13; P-2, 63, 1.67, 23; P-3, 35, 0.97, 13; P-4, 100, 3.33, 37; P-5, 3.6, 2.23, 13; L ratio P-2/-3, 1.79, P-2/-4, 0.63, P-3/-4, 0.35. Leg segments L/H, L/H ratio: I-L-2, 95, 1.46; I-L-3, 110, 1.76; I-L-4, 180, 3.13; I-L-5, 190, 3.8; I-L-6, 170, 3.09; claw L 45. II-L- 2, 125, 1.92; II-L-3, 125, 1.92; II-L-4, 235, 4.09; II-L-5, 235, 4.70; II-L-6, 200, 3.64; claw L 50. III-L-2, 110, 1.83; III-L-3, 110, 2.00; III-L-4, 210, 3.82; III-L-5, 205, 4.10; III-L-6, 185, 3.70; claw L 55. IV-L-2, 140, 2.24; IV-L-3, 140, 2.24; IV-L-4, 268, 4.65; IV-L-5, 250, 4.76; IV-L-6, 225, 3.75; claw L 58. Total L segments 2-6: I-L, 745; II-L, 920; III-L, 820; IV-L, 1023.

Derivatio nominis: levigatus (Latin): smooth–with reference to the absence of integumental papillae.

Remarks: A smooth idiosoma integument is a character state not known from other species in the family Teratothyadidae . The species is furthermore characteristic in the combination of a rather slender chelicera (L/H 9.4–12.1), acetabula not extremely elongated or shortened (Ac-1, 35–39 %, Ac-2, 41–46 % genital field L), and a short palp (total L ♂ 269, ♀♀ 211–231).

Habitat: Low order streams at low elevations.

Distribution: Madagascar, endemic, only found in the extreme south (streams draining Anhohahela National Park).

Figures

FIGURE 26. Family Teratothyadidae, Teratothyas (Ascoteratothyas) levigata (MD 069). a.–d. female; a. idiosoma and gnathosoma in situ, dorsal view; b. idiosoma, genital field; c. chelicera; d. gnathosoma with chelicera, lateral view; e.–g. male; e. palp; f. integument structure; g. venter.