Arrenurus stecki Koenike, 1894

Zawal, Andrzej, 2008, Morphological characteristics of water mite larvae of the genus Arrenurus Dugès, 1834, with notes on the phylogeny of the genus and an identification key, Zootaxa 1765 (1), pp. 1-75 : 56

Arrenurus stecki Koenike, 1894

( Fig. 38 )

Material examined: 10 larvae deriving from 10 females.

Larvae relatively large: idiosoma 214–234 µm long.

Dorsum: Dp large (DpL: 202–216 µm; DpW: 190–200 µm), oval, widest at mid-length. Anterior margin almost straight; posterior margin terminated fairly bluntly. Antero-lateral indents relatively large, slightly obtuse-angled, about 1/5 and 1/3 of dorsal plate length and width, respectively. DpW/Mp1-Mp1 4.5. Lp2, Mh1 smooth. Mp1-Mp1 intermediate (41–46 µm), shorter than Mp2-Mp2 (50–54 µm); Mp1-Lp2 short (34– 38 µm). Venter: CpIm (72–82 µm) clearly longest, followed by CpIIIm (44–48 µm); CpIIm shortest (30–36 µm). Ratio of CpI:CpII:CpIII 2.2:1:1.4. Postero-lateral margins of CpIII strongly indented due to large size of excretory pore plate. Setae on Cp smooth. C1-CpIm (18–22 µm) about 2/3 of C4-CpIIIm (28–31 µm). C1-C2 distance intermediate length (42–46 µm). Expp rhomboid, somewhat longer than wide. Exp located at base of characteristically pointed process, below plate’s mid-point and below E2. E1 located relatively far from anterior margin of Expp. Palps: PIII 1 bipectinate; PV6 thin, long; PIV2, PIV3 relatively long. Chelicerae: First segment (81–84 µm) distinctly bent, margins converging anteriorly. Legs: Shorter than body; LI= LII = LIII ( Fig. 5 ). Tarsi (especially first and second pair) stout. ITi7, ITi8 thin, long. IITi10, IIITi10 relatively short, smooth, located at about 1/3 distance to distal end of tibia (IITi10) and at about 1/2 of tibia (IIITi10). IIITa11, IIITa12, IIITa13 smooth. Hosts: Culicidae (Münchberg 1936) .

Figures

FIGURE 5. Diagram of proportions of leg (LI=LII=LIII) and body length.

FIGURE 38. Arrenurus stecki: A—ventral side, B—dorsal plate, C—excretory pore plate (scale bars: A, B—100 µm; C—20 µm).