The development of Eleutherodactylus latrans

THE mode of embryologic development and the taxonomic position of the barking frog, Eleutherodactylus latrans (Cope), have long been questioned. Strecker (1910) reported the species as having an aquatic development but Wright and Wright (1949) have concluded this record to be in error. Noble (1925) reviewed the taxonomic status of various members of the genus Eleutherodactylus and pointed out that the barking frog was the only member of the genus reported without a terrestrial embryonic development. Piatt (1934) reviewed the morphological position of the species and concluded that it was definitely a member of the genus Eleutherodactylus on the basis of the T-shaped terminal phalanges. Cope (1878) considered the species to be an aquatic breeder. More recent workers (Livezy and Wright, 1947) assume the form to have a terrestrial development, although the life history of Eleutherodactylus latrans has not previously been reported. On the night of April 29, 1949, George Krise, Neal Phillips, Jack Fouquette, and I listened to a male barking frog calling from the side of a canyon near the Medina River in Bandera County, 18 miles west of Medina, Texas. We were able to trace the call to a large rock from under which the amphibian was captured. There was no doubt that it was the calling individual. Under this same rock we found a cluster of 67 eggs in a small pocket of the very rich soil usually found under the rocks of the Edwards Plateau. The pocket was about 4 inches deep and filled with a mixture of eggs and mud. Capture of the male under the rock with the eggs suggests that the male remains with the eggs until they are hatched. The moisture was possibly formed by the urine of the male Eleutherodactylus. It is difficult to explain otherwise the presence of so much moisture in the pocket when it had not rained in the locality for several days. The soil around the pocket was quite firm and devoid of moisture. This dry condition prevailed under other rocks turned in the area at that time. This leads to the hypothesis that the male Eleutherodactylus latrans may prevent dehydration of the eggs by wetting the egg mass with the contents of his bladder. Lynn (1942) reported that the females of Eleutherodactylus nubicola remain with the eggs throughout development. Goin (1947) reported no such phenomena in either the male or female Eleutherodactylus ricordii planirostis. The barking frog eggs were removed to Austin and placed in containers modeled after those used by Goin (1947). The receptacles consisted of flower pots, filled with sand, set in a bowl of water and covered by a piece of glass. They were observed several times each day. More than half of the original 67 were dead when they reached the laboratory. This was probably caused by the heat, the delay of three days before they could be properly cared for, and by the unnatural and undoubtedly rough treatment that they received during this period. In the laboratory the remaining eggs were invaded by molds, which covered them to such an extent that observation was quite difficult. The