The Collothecidae (Rotifera, Collothecacea) of Thailand, with the description of a new species and an illustrated key to the Southeast Asian fauna

Hendrik Segers,Pornsilp Pholpunthin,Phuripong Meksuwan

doi:10.3897/zookeys.315.5330

Abstract

Following previous reports indicating a remarkable high diversity of sessile rotifers in Southeast Asian freshwaters, we report on an extensive study of the diversity of Collothecidae rotifers from fifteen freshwater habitats in Thailand. A total of 13 species, including two additional infraspecific variants, of Collothecidae are recorded, one of which is described as a new species of Collotheca. We further add taxonomic remarks on some of the taxa on record and illustrate the uncinate trophi of several representatives by scanning electron microscopic images. Finally, we provide illustrated identification keys to the Collothecidae recorded to date from Southeast Asia.

Highlights

Collothecidae is one of two families of the rotifer Order Collothecacea
Following previous reports indicating a remarkable high diversity of sessile rotifers in Southeast Asian freshwaters, we report on an extensive study of the diversity of Collothecidae rotifers from fifteen freshwater habitats in Thailand
Realizing that the only available, relatively recent identification work dealing with Collothecidae is in German (Koste 1978), we present a key to the identification of the Collothecidae recorded from Southeast Asia, to facilitate and promote future studies on these remarkable animals

Summary

Introduction

Collothecidae is one of two families of the rotifer Order Collothecacea. The order is diagnosed by the presence of uncinate trophi (Segers 2002, Wallace et al 2006) and a peri-buccal region expanded into a wide infundibulum, while family Collothecidae is further characterized by having a modified corona ciliata (short: corona) consisting of differentiated cilia implanted along the margin of, or grouped on knoblike, lobate or tentacle-like extensions of the infundibulum. These results indicate a relatively diverse Collothecidae fauna in the studied region of Thailand, and the record of one, and possibly two new species leads us to surmise that an even higher and incompletely documented diversity can be expected to occur in Southeast Asia.

Results

Conclusion