Morphological characteristics of water mite larvae of the genus Arrenurus Dugès, 1834, with notes on the phylogeny of the genus and an identification key Author Zawal, Andrzej text Zootaxa 2008 2008-05-07 1765 1 1 75 https://biotaxa.org/Zootaxa/article/view/zootaxa.1765.1.1 journal article 10.11646/zootaxa.1765.1.1 1175­5334 5123752 Arrenurus pugionifer Koenike, 1908 ( Fig. 48 ) Material examined: 5 larvae deriving from 1 female . Larvae large: idiosoma 250–274 µm long. Dorsum : Dp oval (DpL: 232–250 µm ; DpW: 220–224 µm ), widest at mid-length, clearly narrowing anteriorly; posterior margin rounded. Antero-lateral indents small, strongly obtuse-angled, extend to 1/4 and 1/6 of plate’s width and length, respectively. DpW/Mp1-Mp1 4.7. Lp2, Mh1 smooth. Mp1-Mp1 long ( 45–50 µm ), but shorter than Mp2-Mp2 ( 56–64 µm ); Mp1-Lp2 short ( 28–37 µm ). Venter : Median margins of CpI, CpII, CpIII 75–78, 36–38, 59– 62 µm , respectively, their ratio 2.1:1:1.6. All setae on Cp and V 3 bipectinate. C1- CpIm ( 22–25 µm ) about 2/3 of C4-CpIIIm ( 30–32 µm ). C1-C2 long ( 46–52 µm ). Expp oval, rounded anterior and sharpened posterior margins, latter bearing a characteristic process. Plate’s width clearly exceeding its length. Exp situated below plate’s mid-point and below E2. Palps : PIII 1 bipectinate; PV5 pectinate. Chelicerae : Basal segment elongated and slightly bent cylinder-shaped ( 89–94 µm ), margins parallel. Legs : Shorter than body; LI< LII < LIII ( Fig. 3 ). IITi8 thick, short, bipectinate; IITi10 short, pectinate, located close to midpoint of tibia; IIITi10 bipectinate, located distally to mid-point of tibia. Hosts : Culicidae (Münchberg 1936) .