Chamobates pusillus is found in forest soils, heaths and bogs. In forests and in bogs in Western Norway it co-occurred with C. borealis, but was less abundant. It is active under the snow in the winter. It reproduces sexually and its feeding preferences are unknown.
Adult: The length of the body is 345–390 µm, and width is 234–267 µm. The color is middle brown. Rostrum has two teeth, but medial incision is absent (Fig. 1). Most notogastral setae are alveolar (i.e. setae are absent and only their alveoli − small cavities − are seen), except minute setae c2 and of p–series. Porose area Aa is slightly larger than other porose areas. Seta lm is located medially from porose area Aa at the distance of two times diameter of Aa.
Juvenile stages: Larva: body length 208 µm, width 96 µm. Protonymph: body length 221 µm, width 125 µm. Deutonymph: body length 271 µm, width 152 µm. Tritonymph: body length 345 µm, width 165 µm. The color is whitish. Larva is without a gastronotal shield, whereas the shield is present in the nymphs and has 10 pairs of setae; setae p2, p3 and of c–series are inserted on unsclerotized cuticle (Fig. 2). During the development the length of most prodorsal setae and notogastral seta c3 increases, and of other notogastral setae decreases.
Chamobates pusillus is similar to C. borealis, but differs from it by several clear morphological characters. The nymphs of C. pusillus lack a humeral organ (Fig. 2), which is present in C. borealis (Fig. 3). Adult C. pusillus lacks a medial incision on the rostrum (Fig. 1), which is present in C. borealis (Fig. 4). Chamobates pusillus lacks most notogastral setae (only their alveoli, i.e. small cavities, remain), while in C. borealis these setae, although minute, are present. In C. pusillus porose area Aa is only slightly larger from other porose areas, while in C. borealis it is distinctly larger. Notogastral seta lm in C. pusillus is located medially from Aa at the distance of two times diameter of Aa, while in C. borealis it is placed posterior-medially to porose area Aa at the distance equal to the diameter of Aa.
Chamobates pusillus reproduces sexually. Its development has not yet been studied, but is probably similar as in its congener [C. subglobulus (Oudemans, 1900)], which developed from egg to adult during 71–124 days in 18–20 °C. Its feeding preferences are unknown.
Chamobates pusillus occurs in the Palearctic, which is northern Eurasia and North Africa.
It is found in forest soils, heaths and bogs.
Findings in Norway
It has been found in forests and in bogs in Western Norway, where it co-occurred with C. borealis, but was not abundant. It was active under snow in winter.
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Siden siteres som:
Seniczak A (2020). Chamobates pusillus (Berlese, 1895). www.artsdatabanken.no/Pages/286334. Nedlastet <dag/måned/år>