Trombidiformes 1 79 



keglike with two end setae, except for Monotrichobdella which pos- 

 sesses one. Normally the genu and tibia are bent, giving the palpi 

 an elbowed appearance. Chelicerae are elongated (more compact in 

 Cyta) with one or more dorsal setae and very small, usually weak 

 shears. Three pairs of genital suckers are present. Grandjean 1938 has 

 divided the BdelUdae into four subfamilies. 



Key to the Bdellidae 



1. With well-developed genital tracheae; venter of rostrum with only 

 two pairs of strong setae and two pairs of weak anterior setae 2 



Without well-developed genital tracheae; venter of rostrum with 

 six pairs of strong setae and two pairs of weak anterior setae 3 



2. With unpaired seta anterior to genital opening Cytinae 

 With pair of setae anterior to genital opening Spinibdellinae 



3. Trichoboth (long sensory seta) on tibiae i, n, and rv and tarsi 



m and iv Odontoscirinae 



Trichoboth on tibiae i and iv and tarsi ni and rv Bdellinae 



Cytinae Grandjean, 1938 

 Genera: 



1. Cytav. Hey den, 1826 



Type. Scirus latirostris Hermann, 1804 



2. Trachymolgus Berlese, 1923 



Type. Bdella nigerrima G. Canestrini and Fanzago, 1876 



Spinibdellinae Grandjean, 1938 

 Genera: 



1. SpinibdellaThoT, 1930 



Type. Spinibdella reducta Thor, 1930 



2. Biscirus Thor, 1913 



Type. Bdella silvatica Kramer, 1881 



3. Monotrichobdella Baker and Balock, 1944 



Type. Monotrichobdella max-osburni Baker and Balock, 1944 



Bdellinae Grandjean, 1938 



Genus: 



Bdella Latreille, 1795 (= Scirus Hermann, 1804, non Thor, 1931) 

 Type. Acarus longicornis Linnaeus, 1758 (= Scirus vulgaris Her- 

 mann, 1804) 



