286 A7inals Entomological Society of America [Vol. IX, 



As a result the citrus red spider has never been technically 

 named or described. It therefore becomes necessary to name 

 and describe it. 



Tetranychus citri sp. nov. 



ORIGINAL DESCRIPTION. 



Distinctly velvety-red in color. In size larger and more obese than 

 the majority of red spider species. Female: length, .305 mm., width, 

 .230 mm. A single eye cornea on each side, twice as far behind the 

 subfrontal bristle as the latter's distance from the frontal bristle. 

 Dorsal bristles long, stout, arising from prominent tubercles (see 

 Plate XIV, Fig. 3) ; subfrontal bristles barely 3 times as long as frontals 

 (see Plate XIV, Fig. 2) ; bristles sparsely pilose. Legs paler than body 

 color, bristles 26, arranged chiefly in four longitudinal rows (see Plate 

 XIV, Fig. 8) . Mandibular plate abruptly narrowed anteriorly, tip rounded 

 with an almost imperceptible emargination. Palpus is provided (see 

 Plate XIV, Fig. 9), with a comparatively short "thumb," bearing a ter- 

 minal, slightly clavate "finger" whose base is less than half the width 

 of tip of "thumb"; with two pseudo-fingers arising on either side of the 

 upper distal corner, which are not greatly thicker than hairs ; on upper 

 side hardly midway to base with a small "finger" between which and 

 base are two, short, stout hairs; near the lower center of the outer 

 side of the ' ' thumb ' ' with a hair which reaches to the tip of the terminal 

 "finger" ; with the claw on the penultimate joint stout and reaching to 

 the dorsal "finger"; a strong hair arising laterally from the center of 

 the penultimate joint, another arising from the center of the dorsal 

 face of this joint which equals the claw, and a short, weak hair with its 

 origin on the inner base of claw; and with a very strongly tubercled 

 spur arising distally from the top of the antepenultimate joint of the 

 male (see Plate XIV, Fig. 7). The legs (see Plate XIV, Fig. 1), are rela- 

 tively short; femur somewhat more than twice as long as wide, barely 

 equalling tarsus; tibia a little longer than patella which is one-third again 

 as long as trochanter. Tip of tarsus (see Plate XIV, Fig. 6), bears a claw 

 which is rather straight for two-thirds its length and then bent sharply 

 downward; at a point one-third the length of the claw from its base 

 arise six slightly curved spurs whose tips surpass that of the main claw: 

 the four usual capitate hairs arise two on either side of the base of the 

 claw. 



The male is considerably smaller than the female (length .210 mm., 

 width .146 mm.), abruptly narrowed posteriorly. The legs appear 

 longer in proportion to the body than in the case of female, and are 

 salmon pink. The distribution of dorsal bristles (see Plate XIV, Fig. S), 

 is similar to that of female. Penis (see Plate XIV, Fig. 4), comparatively 

 short; inner lobe long, rod-like, about 3 times as long as the shaft; 

 shaft very stout and short, becoming abruptly smaller distally, and 

 bent upward at an angle of 120 degrees to form the attentuate hook 

 which is considerably longer than the shaft; basilar lobe present on 

 upper side of shaft as a strong, conical projection; hook possessing no 

 barb, being spine-like terminally. 



