452 
Psyche 
[September-December 
Aliatypus janus new species 
Figures 18-24, 55 , 66, 83-84, 102-105, 132-143. Map 2. 
Type specimens and etymology. Holotype male from 5 mi. south 
of Hume Lake, Fresno Co., California, 16 October 1973 (W. R. 
Icenogle). One male and three female paratypes. Janus was the 
Latin god of gates and doors. 
Diagnosis. Males: A. janus is very similar to A. isolatus; CL/ 
ALS (Table 1) is useful in separating these two allopatric species. 
A. janus is distinct from closely related A. calif ornicus in the absence 
of an ICS keel (Figs. 102-105) and in IML/ITarL (Table 1). 
A. janus is distinct from A. aquilonius in palpus tip form (Figs. 102- 
105), SW/PSS, CL/PSS, and CL/ALS (Table 1). A. janus 
differs from A. gnomus in CL/ALS, CL/AMD, and body size 
(Table 1). Sympatric A. erebus differs from A. janus in CL/ 
PTT, PSL/PSS, CL/IFL (Table 1), and palpus form (Figs. 
102-105). A thompsoni, also sympatric with A. janus, is distinct 
in PSL/PSS, CL/IML (Table 1), thoracic groove form, and 
leg I setation. Other species can be separated from A. janus with 
an appropriate ratio from the following (Table 1): CL/ALS, 
PTX/PTL, and PTT/PTL. Females: The only really helpful 
character to use in separating A. janus from closely related A. 
isolatus is SL/SW (Table 2). Only seminal receptacle form ap- 
pears useful in separating A. janus from closely related A. cali- 
f ornicus (See A. calif ornicus diagnosis). A. janus has a larger 
IFL/IVFL, longer ITarL, and more IMS (Table 2) than does 
A. aquilonius. A. janus is distinct from A. gnomus in AMD/ 
AMS, IFL/IVFL, body size (Table 2), and seminal receptacle 
form (Figs. 132- 143). A. janus is distinct from sympatric A. 
erebus in seminal receptacle form (Figs. 132-143), CL/PSL, SW/ 
PSL, and IFL/IVFL (Table 2). A. janus is distinct from sym- 
patric A. thompsoni in thoracic groove form, seminal receptacle 
form (Figs. 132-143), CL/PSS, and PSL/PSS (Table 2). The 
remaining Aliatypus species can be separated from A. janus by either 
CL/IFL or IFL/IVFL (Table 2), and by seminal receptacle form 
(Figs. 1 32- 1 43). 
Description. See Tables 1-3. 
Males: Carapace. Thoracic groove a deep pit; usually roughly 
triangular or T-shaped. Postocular setae form moderately long nar- 
row row. Sternum. Fig. 55. Posterior sigilla small to medium sized 
and well separated. Pedipalps. Figs. 83-84, 102-105. Tibia markedly 
swollen ventrally near distal end. Embolus base distant from ICS 
