648 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 56. 



Tragardh (18) writes: "To this genus (ScMzotetranychus) probably 

 belongs T. mytilasjyidis Riley/ and to judge from Ewing's description 

 of it, and Zachor's figure of ^S. scliizopus the penes of the two species 

 seem to be of the same shape." Plowever, a comparison of Zacher's 

 figure 4 and the writer's figure 4,^* of the penis of S. scMzopus and T. 

 citri (mytilaspidis, authors not Riley) respectively, shows rather con- 

 clusively the marked difference in the penis type; furthermore, as 

 elsewhere stated herein, it develops that the tarsal claw of Tetranychus 

 citri McGregor is not simply two cleft, but possesses in addition four 

 empodial spurs, and is accordingly referable to a different genus — 

 Paratetranychus. 



SCHIZOTETRANYCHUS SCHIZOPUS Zacher. 



Tetranychus schizopus Zacher. Jan., 1910, Mitt. Kais. Biol. Anst. f. Land- imd 

 Forst., Heft 9. p. 40. 



Zacher (13) described this species in 1910 from material on various 

 species of willows collected at Dahlem, Germany. 



SCHIZOTETRANYCHUS LATITARSUS Ewing. 



SchhoUtranychua latitarsus Ewing. 1917. Tourn. Econ. Ent., vol. 10, no. r>, p. 498. 



Preserved specimens yellowish and reddish, with dark spots show- 

 ing through the body wall. Cephalothorax fully as broad as long. 

 Mandibular plate or rostrum over twice as long as 

 broad. Apparently two eyes on each side of 

 cephalothorax, but only one with a perfect cornea. 

 Palpi prominent; palpal claw ver}^ short, stout, 

 and but slightly hooked; "thumb" swollen, short, 

 not reacliing tip of claw and apparently without 

 digit. Abdomen rather strongly arched and even- 

 ly rounded behind except for the anal papilla. 

 Above the abdomen is sparsely clothed with long, 

 prominent, slightly curved, minutely pectinate 

 setae. Legs moderate; tarsus of leg I but slightly 

 longer than tibia, very broad and truncate at its 

 tip: at its tip above it bears a large tactile seta 

 much longer than the tarsus itself. The tarsi of 

 the legs are each provided distally with two sub- 

 equal, simple claws, and four tenent hairs; of the 

 latter the two inner are longer than the two outer, 

 and all are at least twice as long as the claws. Length, 0.36 mm. ; 

 width, 0.23 mm. 



From Pasadena, California; on bamboo; by C. P. Clausen. De- 

 scribed from several specimens. This species is probably an intro- 

 duced one, according to Ewing. 



Fig. 2.— SctllZOTETRA- 

 nychus latitae.su.s 

 Ewing. Tarsus anh 

 its appendage.s 

 (ArxER Ewing). 



» The true mytilaspidis Riley belongs to the genus PerUhalodes and is not a red spider. 

 • Ann. Ent. Soc. Amer., vol. 9. no. 3, pi. 14. 



