Arrenurus maculator (O. F. Müller, 1776)

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 : 33

Arrenurus maculator (O. F. Müller, 1776)

( Fig. 1 )

Hydrachna maculator O. F. Müller, 1776

Arrenurus pseudomaculator Piersig, 1901

Arrenurus coronator Georgewitsch, 1906

Material examined: 10 larvae deriving from 10 females.

Larvae medium-sized: idiosoma 200–210 µm long.

Dorsum: Dp relatively small (DpL: 188–196 µm; DpW: 140–146 µm), very similar to A. cuspidator , dif- fering in antero-lateral indents, which are slightly shallower and reach to about 1/5 of DpL. DpW/Mp1-Mp1 2.4. Lp2, Mh1 smooth, thin. Mp1-Mp1 relatively long (58–61 µm), longer than Mp2-Mp2 (44–50 µm); Mp1- Lp2 short (30–36 µm). Venter: Median margins of CpI, CpII, CpIII measure 60–62, 31–33, 31– 32 µm, respectively; their ratio 1.9:1:1. C1 bipectinate; C2, C3, C4 pectinate. C4 with brush of hairs at base. C1-CpIm (19– 22 µm) somewhat longer than that in A. cuspidator , about 4/5 of C4-CpIIIm (28–30 µm). C1-C2 intermediate (38–41 µm). Expp almost identical to that in A. cuspidator , slightly narrower. Exp located distinctly below mid-point of plate, below E2 ( Fig. 1 ). Palps: Similar to those in A. cuspidator ; PV8 clearly longer. Chelicerae: Identical to those in A. cuspidator ; a small difference lies in their being shorter (68–71 µm). Legs: Shorter than body; LI< LII = LIII ( Fig. 4 ). ITi8 intermediate length; IITi10 very long and, similarly to IIITi10, located in distal part of tibia. Hosts: Coenagrion puella , C. pulchellum , C. scitulum (Ram.) , Cercyon lindenii , Erythromma najas , Enallagma cyathigerum , Ischnura elegans ( Davids 1997; Baker et al. 2006; Baker et al. 2007).

Figures

FIGURE 1. Arrenurus maculator: A—ventral side, B—dorsal side, C—excretory pore plate, D—pedipalp, E—chelicera, F—leg I, G—leg II, H—leg III (scale bars: A, B—100 µm; C, D—10 µm; E—50 µm; F, G, H—20 µm).

FIGURE 4. Diagram of proportions of leg (LI<LII=LIII) and body length.