Trombidiformes 221 



Genera: 



1. Phytoptipalpus Tragardh, 1904 



Type. Phytoptipalpus paradoxus Tragardh, 1904 



2. Brevipalpus Donnadieu, 1875 



Type. Brevipalpus obovatus Donnadieu, 1875 



3. Dolichotetranychus Sayed, 1938 



Type. Stigmaeus fioridanus Banks, 1900 



4. Pentamerismus McGregor, 1949 (= Aegyptobia Sayed, 1950) 

 Type. Tenuipalpus erythreus Ewing, 1917 



5. Phyllotetranychus Sayed, 1938 (according to Vitzthum may be the 



same as Raoiella Hirst) 

 Type. Phyllotetranychus aegyptium Sayed, 1938. 



6. Pseudoleptus BruydinX, \9\l 



Type. Pseudoleptus arechavalatae Bruyant, 1911 



7. Raoiella Hirst, 1924 (= Rondaniacarus Oudemans, 1938) 

 Type. Raoiella indica Hirst, 1924 



8. Tegopalpus Womersley, 1940 



Type. Tegopalpus conicusV^omQrsXQy, 1940 



9. Tenuipalpus Donnadieu, 1875 



Type. Tenuipalpus palmatus Donnadieu, 1875 

 10. Trichadenus Rondani, 1879 



Type. Trichadenus sericariae Rondani, 1879 



Discussion: The life history of this family may be illustrated by that 

 of Brevipalpus inornatus (Banks) as worked out by McGregor 1916. 

 The egg is thickly elliptical in outline, is about 96 ^ long by 67 ix wide, 

 and is deposited with the long axis perpendicular to the leaf. The fe- 

 male usually lays the egg in a crevice or abrasion, in old molted skins, 

 or in the groove by the midvein. They are often closely packed in 

 clusters of several hundred, each female laying approximately twenty 

 eggs. In South Carolina during the summer the eggs hatch in about 

 eight days and the six-legged larva emerges. The average larval dura- 

 tion is 4.7 days. The larvae molt into protonymphs whose duration is 

 about 4.5 days. The deutonymphal stage lasts about four days, the 

 total being about twenty-one days. There are possibly six to seven 

 generations per year in South Carolina, the mite being found through- 

 out the entire year. All stages are more or less similar. 



The genus Phytoptipalpus Tragardh is a typical phytoptipalpid but 

 lacks the fourth pair of legs. Sayed 1942 records it as having two 

 "larval" stages before it attains sexual maturity. This genus, along 

 with Tenuipalpus eriophyoides Baker nymph, indicates the phylo- 

 genetic relationship between the Eriophyidae, which are elongate, an- 



