Abstract

ABSTRACT In a single blind study the gender of nine adult Mexican beaded lizards, Heloderma horridum and 35 adult Gila monsters, Heloderma suspectum of known sex was determined by two dimensional ultrasound imaging of the ventral tail just distal to the cloaca. In each case subjects could be sorted into two distinct morphologic groups. Group 1 animals had large, variably hypoechoic, paired soft tissue structures in the ventral aspect of the tail spanning 2 cm distal to the vent, while the distal tail lacked these structures. Group 2 animals lacked this characteristic altogether, giving the ventral tail a much more consistent ultrasonic complexion along the entire length. The most logical conclusion for this difference was the presence of paired hemipenes in group 1 animals. Using this premise, subjects in group 1 were declared males, while group 2 animals were declared females. The predictions matched the known sexes of each individual in every case for adult lizards. One juvenile Gila monster could not b...

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call