Reproduction in the San Lucan banded rock lizard, Petrosaurus thalassinus (Phrynosomatidae) from Baja California Sur, Mexico.(Research Notes)

Petrosaurus thalassinus is restricted to the Cape Region of Baja California, occurring in four disjunct populations (Grismer 2002). The biology of this species was summarized by Grismer (2002), however information on the reproductive biology in P. thalassinus is limited to anecdotal accounts (Asplund 1967; Grismer 2002). The purpose of this paper is to present information on the reproductive cycle from a histological examination of gonadal material and to provide the first clutch sizes for this species.

Forty-four male (mean snout-vent length, SVL = 110 mm [+ or -] 19 SD, range = 80-152 mm), sixteen female (mean SVL = 90 mm [+ or -] 14 SD, range = 71-110 mm), and two neonate P. thalassinus (mean SVL = 35 mm [+ or -] 1.4 SD, range = 34-36 mm) from the Natural History Museum of Los Angeles County (LACM), San Diego Society of Natural History (SDSNH) and University of Arizona (UAZ) were examined (Appendix).

The left testis and left ovary were removed from males and females respectively. Gonads were embedded in paraffin, sectioned at 5 [micro]m and stained with Harris' hematoxylin followed by eosin counterstain. Oviductal eggs or enlarged follicles (> 6 mm length) were counted but not examined histologically. An unpaired t-test was performed to compare …