Jeff Hollenbeck kindly labeled this image to indicate anatomical features:
B = genital bulb
CH = chelicera
F = femur
P = procursus
SP = spur on procursus
TR = trochanter
See paper:
Copulatory Mechanism in Holocnemus pluchei and Pholcus opilionoides, With Notes on Male Cheliceral Apophyses and Stridulatory Organs in Pholcidae (Araneae)