Megophrys nasuta is a member of the superfamily Megophryid in the family Pelobatidae. This is the largest and most diverse family-level group of non-neobatrachian frogs. All megophryids for which data are available have unusually ossified intervertebral disks, and hyoid plates that lack most of the ceratohyals. For this reason there are no known fossils (sci-ctr.edu 1996). This animal is a perfect example of why scientific names are so important. This frog is known by several common names which such as, 1) Asiatic Horned Toad, 2) Malayan Horned Frog, 3) Malaysian Leaf Frog, 4) Asian Spadefoot Toad , just to name a few. Without the designation of a single scientific name it would be next to impossible to collate knowledge of this species.
Status: no special status, however it is threatend by loss of habitat, and overexploitation by the exotic pet trade (sci-ctr.edu 1996).
IUCN Red List of Threatened Species: least concern
Development - Life Cycle: metamorphosis
Megophrys nasuta is a ferocious predator. It uses it's cryptic coloration and unusual appearance to prey on a wide variety of unsuspecting animals on the forest ground. Typically they feed on arachnids, nestling rodents, lizards and other frogs (Obst et. al 1984). Aside from these usual prey items, they are also partial to crabs and scorpions, which happen to be their main source of food (sci-ctr.edu 1996).
Megophrys nasuta can be found on the forest floors of Southeast Asia, from the foothills of the Himalayas to the Indo-Australian Archipelogo (Obst et. al, 1984).
Megophrys nasuta prefer a spacious, permanently damp and relatively cool environment. Their optimal temperature is between 22 -24 degrees C. They can be found on the rain forest floors, usually near small streams (sci-ctr.edu 1996). They are known to use both land and water areas extensively (Bartlett 1996).
Megophrys nasuta is an animal perfectly designed to fit its surroundings. They are attractive however modestly colored. Hidden dorsally in grays, tans, russets, or browns which become darker laterally, they are almost invisible among the forest leaf litter (Bartlett 1996). Their smooth skin is modified so that they resemble dead leaves on the forest floor. A huge angular head with supraciliary projections above each eye
and nasal area, along with its cryptic coloration cause it to resemble dry leaves. Skin folds from above the eye to the tympanum and shoulders; and toes which are only webbed at the bases, also contribute to their leaf-like appearance (Obst et. al 1984). Males are often substantially smaller than females, rarely more than half their size. Females usually attain just over 5 inches (12.7cm) in length (sci-ctr.edu 1996). Using its leaf-like appearance for camouflage, Megophrys nasuta is virtually undetectable in the leaf litter of the forest floor unless it moves.
Other Physical Features: ectothermic ; bilateral symmetry
Little information is available on the natural breeding of these frogs, however captive reproduction is fairly common. They are oviparous with the females attaching the egg clusters to the underside of rocks and logs which are water swept and are partially or entirely submerged. If the eggs are attached to surfaces in water the tadpoles hatch and begin life in their aquatic habitat. However if the eggs are laid partially submerged, the eggs slide down to the water on threads of thin, gelatinous egg coverings. The eggs are large and relatively few in number (Bartlett 1996). The larvae are elongated , with a very large , funnel - shaped mouth. They cling with their mouths at the surface while their body hangs vertically. This helps them in their feeding strategy which is specialized
on microorganisms at the waters surface (Obst et. al 1984).
Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate)
The long-nosed horned frog (Pelobatrachus nasutus), also known as the Malayan horned frog or Malayan leaf frog is a species of frog restricted to the rainforest areas of southern Thailand and Peninsular Malaysia to Singapore, Sumatra, and Borneo. However, records from Thailand to the Sunda Shelf may apply to another, possibly unnamed species.[3]
Formerly placed in the genus Megophrys, it was reclassified into the genus Pelobatrachus in 2021.[3]
This species is a large frog ranging from 100–120 mm in length. They are light to dark brown on the dorsal surface with varying patterns and camouflage very well with the forest floor. The throat is black-dark brown and diffuses into cream-yellow halfway along the ventral surface. The upper eyelids and snout are drawn out into long triangular projections, forming what looks like "horns", giving them their common name. There are two pairs of dorsolateral skin folds running down this species back. One pair starts behind the eye and ends near the groin, the other pair starts at corner of the eye and ends roughly halfway between the armpit and groin. The dorsum has randomly scattered, enlarged tubercles. Arms and legs are barred with skin folds and are mottled cream and different shades of brown. The toes are slightly webbed and the fingers are free from webbing. The tympanum is indistinct and the iris is golden brown.
This species lives in permanently damp and cool lowland and submontane rainforests among leaf litter. The call is a loud, resonating, metallic "honk" or "henk". Breeding takes place in streams, female frogs attach the eggs to the underside of partially or full submerged rocks or logs. The capsules are large and few in number. This species may lie still on the forest floor waiting for an unsuspecting prey item to pass by, they then lash out and engulf the prey. They typically feed on spiders, small rodents, lizards and other frogs.
This species is unlikely to get confused with any other genus of frog and can be distinguished from other species of the genera Pelobatrachus and Megophrys by the elongated nose and the two pairs of dorsolateral skin folds.
The long-nosed horned frog (Pelobatrachus nasutus), also known as the Malayan horned frog or Malayan leaf frog is a species of frog restricted to the rainforest areas of southern Thailand and Peninsular Malaysia to Singapore, Sumatra, and Borneo. However, records from Thailand to the Sunda Shelf may apply to another, possibly unnamed species.
