New Genus of Tree Frog Discovered

In News

Scientists discovered a new genus of tree frogs.

In-Detail

• Researchers from the University of Delhi and the Zoological Survey of India (ZSI) discovered a new genus of tree frogs.
• The tree frogs are found in the Andaman Islands and the Northeast.
• The tree frog is named Rohanixalus after the Sri Lankan taxonomist Rohan Pethiyagoda.
•  The frogs of the new genus have a small and slender body with a size of about 2 to 3cm.
• They have a pair of contrastingly coloured lateral lines on either side of the body with tiny brown speckles scattered throughout the upper body.
• the frogs lay eggs in arboreal bubble-nests which are light green.
• Using DNA sequencing, researchers have found that the new genus is the distinct evolutionary lineage from previously known tree frog genera.
• Scientists studied the external morphology of adults and tadpoles, calls, phylogeny and breeding biology of tree frog species.
• These frogs are distributed across South, Southeast and East Asia.
• The study was contributed by scientists from China, Indonesia and Thailand.
• The tree frog belongs to the family of Rhacophoridae is the 20^th recognized genus that comprises 422 known Old World tree frog species that are found in Asia and Africa.
• There are 8 frog species in the genus Rohanixalus and are known to inhabit the forest as well as human-dominated landscapes.
• These are mostly found in the northeast, Andaman Islands, Thailand, Malaysia, Myanmar, Laos, Vietnam, Indonesia and Cambodia and Southern China.
• Rohanixalus vittatus (Stripped Bubble nest frog) is the first member of the tree frog family and is  found on the Andaman Island.
• This research uncovers the new distribution pattern of tree frogs which provides evidence for faunal exchange between Andamans and the Indo-Burma region.

Feature of the New Tree Frog

• The genus has a unique behavioural trait of maternal egg attendance.
• The female frogs watch over the egg clutches until tadpoles are hatched and the female frog assists the tadpoles into the water.
• The females sit over the eggs during the first three days after laying eggs.
• They produce a gelatinous secretion with which she glazes the egg mass through the clockwise movement of her legs.
• This produces necessary moisture to the eggs laid on exposed leaf surfaces and protects from insect prediction.
• Field studies revealed that the frogs lay eggs in clutches and the researchers have founds eggs at various developmental stages on a single leaf or plant.
• The frogs all display territorial behavior and frequent male-male combats which involve pushing, kicking, and dislodging to successfully mate with the female.