Nonnatives - Javan Filesnake

Florida's Exotic Wildlife. Species detail.

First year: 1970s

Extirpated year:

Established status: Species have populations whose status is unknown.

Estimated Florida range: 1 county  Not reported breeding

Statewide trend: Unknown status

Threats to natives: Preys on fish and possibly frogs.

Species Account: This species is native to coastal areas of India, the Malay Archipelago, Southeast Asia, and the Indonesian islands west of Australia, where it inhabits tropical coasts, sluggish streams, and freshwater and brackish swamps (Trutnau 1986). Dorsal coloration is brown, and the sides and belly are pale yellow. Juveniles have irregular, longitudinal blotches. The loose, baggy skin is covered with small rough scales that do not overlap and have a sharp, triangular ridge. Both dorsal and ventral scales have the same size and shape. The flat, broad head is approximately the same diameter as the body, and the valved nostrils are situated on top of the head. File snakes are almost totally aquatic and can stay submerged for over 40 minutes (Trutnau, 1986). Juveniles, however, are semi-terrestrial until they develop the baggy skin. When swimming, the loose skin causes the thick body to flatten vertically. It typically hides in burrows in river banks or under debris during the daytime, emerging at night to forage for fishes and frogs, or to ambush prey while anchored by its short, prehensile tail. Females are sexually mature at 114-130 cm (45-51 in) snout-vent length (SVL) and 2000 g (4.4 lb), whereas males mature at 100 cm (39 in) SVL and 900 g (2.0 lb) (Shine et al. 1995). In Sumatra, the mean SVL for adult males is 118 cm (46 in) and for females is 135 cm (53 in). In Sumatra, females typically give birth around December to an average of 29.3 (range = 13-52) young, which measure 28-36 cm (11-14 in) SVL (Shine et al. 1995).

Habitats: Lake

County First Year Extirpated Year Breeding status Notes
DADE 1970s


Not reported breeding Specimens were occasionally captured or observed in a rock pit northwest of Miami from the late 1970s until ca. 1990 (J. A. Wasilewski, Natural Selections, Homestead, personal communication); 1 seen floating dead in ca. 1998 (B. Vath, personal communication); population was presumably reproducing but may now be extirpated.


Shine, R., P. Harlow, J. S. Keogh, and Boeadi. 1995. Biology and commercial utilization of acrochordid snakes, with special reference to karung (Acrochordus javanicus). J ournal of Herpetology 29:352-360.

Trutnau, L. 1986. Nonvenomous snakes. Barron's Educational Series, Hauppauge, New York. 191pp.

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