A new species of Rangabradya (Copepoda, Harpacticoida, Ectinosomatidae) from a cave in Satun Province, southern Thailand.

Chaichat Boonyanusith,Sujeephon Athibai

doi:10.3897/zookeys.1009.54554

Abstract

A representative of the family Ectinosomatidae was discovered in a temporary pool in a cave in the Satun Province, southern Thailand. Based on the characteristics of the antennary exopod, armature of the female fifth leg, and configuration of the male sixth leg, a new species of the genus Rangabradya was identified, representing the first record of the genus in the continental waters of Thailand and in Southeast Asia. The new species can be distinguished from Rangabradya indica by the configurations of the fifth and the sixth legs in both sexes, the body ornamentation of the urosomite, and the armature of the mouthparts. These structures show a more primitive state in the new species. Accordingly, a new subgeneric rank in the genus Rangabradya, Siamorangabradyasubgen. nov, was established to accommodate the Thai species and Rangabradya (Siamorangabradya) wongkamhaengaesubgen. et sp. nov. was described. Also, the key to all 23 genera of the family was updated.

Highlights

Satun Province is located in southern Thailand and is part of the continental area of the Sunda Subregion (Fig. 1A)
A rich diversity of fauna endemic to the country is expected for Satun Province, where several new taxa have recently been discovered from karstic areas (e.g., Sumontha et al 2014; Liu et al 2017; Nilsai et al 2017; Promdam et al 2017)
Among the genera currently known as members of the family Ectinosomatidae, the genus Rangabradya Karanovic & Pesce, 2001 is a subterranean freshwater representative

Summary

Introduction

Satun Province is located in southern Thailand and is part of the continental area of the Sunda Subregion (Fig. 1A). Two new copepod species from this province have been described, namely, Onychocamptus satunensis Boonyanusith, Saetang, Wongkamhaeng & Maiphae, 2018 and Boholina laorsriae Boonyanusith, Wongkamhaeng & Athibai, 2020 (Boonyanusith et al 2018, 2020). The latter is the first record of the subterranean Calanoida in Thailand. Among the genera currently known as members of the family Ectinosomatidae, the genus Rangabradya Karanovic & Pesce, 2001 is a subterranean freshwater representative. An updated key to all 23 genera of the family is provided

Materials and methods

Findings

Discussion