Aturus crinitus Thor, 1902

Gerecke, Reinhard, 2014, Studies on European species of the water mite family Aturidae Thor (Acari: Hydrachnidia), Zootaxa 3841 (1), pp. 1-46 : 8-9

Aturus crinitus Thor, 1902

Figs 2 , 5

Material examined. Bosnia and Hercegovina: YU 3 (3/12/0), YU 15 (1/0/0), YU 44, (2/1/0). Greece: Makedonia, GR 48 (1/9/0). Italy: Basilicata, I 442 (1/0/0), I 1125 Int (1/0/0); Calabria, I 107 (2/4/0), I 419 (1/0/0), I 1132 (3/4/ 0); Sicily, I 1 (2/28/0), I 98 (2/1/0), I 100 (1/1/0), I 179 (1/1/0), I 180 (19/9/0), I 181 (12/9/0), I 193 (6/6/0), I 234 (1/ 0/0), I 237 (46/44/0), I 470 (1/0/0), I 480 (2/0/2), I 481 (3/1/0), I 500 (6/1/0), I 552 (2/0/0), I 1067 (1/1/0), Macedonia: YU 50 (1/8/0), YU 51 (0/3/1). Montenegro: YU 32 (0/1/0).

Uncertain records. Italy: Basilicata, I 1124 Int (0/1/0); Calabria, 1065 (0/1/0), I 1105 (0/1/0), I 1129 (0/3/0); Sicily, I 37 (0/2/0), I 178 (0/1/0), I 250 (0/4/0), I 479 (0/3/1), I 548 Int2 (0/1/0), I 553 Int (0/1/0), I 1068 (0/1/0), I 1138 Int (0/3/0); Macedonia: YU 51 (0/3/1); Montenegro: YU 32 (0/1/0).

Remarks. Females collected together with male A. crinitus are characterized by a low distance ratio Dgl-3-4/ 4–5 of 1.4–2.0; and genital plates with only 2–3 setae located near medial acetabula. In other character states geographical differences are found: As compared with females from the Mediterranean area, Central European females have higher numbers of acetabula (12–16 vs. 8–11 pairs) and lateral Vgl fused to primary ventral sclerotization, but medial ones lying in secondary sclerotization (Mediterranean females with both Vgl in primary sclerotization, the lateral one generally slightly more distanced from posterior primary sclerotization border which is straight or slightly concave in this part).

Associated males do not show noteworthy differences except for their generally minor size (e.g., idiosoma L in general <300, central European specimens 370–410 µm). These differences are remarkable and suggest that Aturus crinitus could represent a group of cryptic species. This topic merits further research, along with diagnostic differences in comparison with A. villosus Motaş & Soarec, 1939 , a species similar in size to the Mediterranean populations of A. crinitus , but with males differing in lower number of bulbous setae and shortened distal segments of IV-L.

Habitat and distribution. Different types of low order streams, in Central Sicily also under semiarid conditions with elevated electrolyte concentrations ( Gerecke 1991a). It is noteworthy that this species has not been detected on Corsica and Sardinia. Absence of this species which is rather frequently recorded from most parts of Europe would be a remarkable zoogeographical feature of the fauna of the islands.

Figures

FIGURE 2. Aturus crinitus (I 181), SEM photographs. A. – D. male; A. IV-L- 4 – 5 anteroventral; B. IV-L- 4 – 5 posteroventral; C. dorsum; D. posterolateral idiosoma; E. female genital field posterolaterally. Scale bars: A – B, E: 20 µm, C – D 50 µm.

FIGURE 5. Aturus crinitus. A. – B. female; A. venter; B. dorsum; C. male dorsum. Scale bar = 100 µm.