Trombidiformes 



245 



Genus: 



Calyptostoma Cambridge, 1875 (= Smaris Berlese, 1887) 

 Type. Acarus velutinus Miiller, 1778 (= Calyptostoma hardyi Cam- 

 bridge, 1875) 



Discussion: A little-known group of predaceous mites. 



Trombidiidae Leach, 1815 



Figure 182 



Diagnosis: Nymphal and adult trombidiids can usually be recognized 

 by their dense coat of setae that gives them a velvet-like appearance 

 and by the division of their body into three more or less distinct sec- 

 tions — gnathosoma, propodosoma, 

 and hysterosoma. The body, how- 

 ever, is never 8-shaped. The cheli- 

 cerae consist of two segments, a 

 basal muscular one and a curved, 

 bladelike distal segment that is 

 provided with sawlike teeth on its 



Figure 182 a Microtrombidiiim hys- Figure 182 h AUothrombium neapoli- 

 tricinum (Canestrini). Dorsal view of tanum Oudemans. Dorsal view of 

 adult. (After Vitzthum 1926) larva. (After Oudemans 1912) 



dorsal edge The stigmata open near the median, dorsal, proximal 

 surface of the chelicerae and usually do not have free peritremes. 

 The palps have five segments, and the palpal tarsus opposes a ter- 

 minal tibial claw in thumblike fashion. The legs have six (exception- 

 ally five) segments. A dorsal scutum or crista metopica is found on 

 the median portion of the propodosoma. One (exceptionally two) 

 pairs of sensillae are on the lateral expansions of the scutum. Anteri- 



