Cave dwelling Onychophora from a Lava Tube in the Galapagos

Luis Espinasa,Aaron Addison,Christina A Fratto,Jordi Espinasa,Radha Garvey,Theofilos Toulkeridis,Steven Taylor

doi:10.3897/subtbiol.15.8468

Abstract

A new population of velvet worms (Onychophora) inhabiting a lava tube cave in the island of Santa Cruz, Galapagos, is reported here. The population size is large, suggesting that they may be troglophilic. Its members are darkly pigmented, with no obvious troglomorphic features. Their 16S rRNA sequence showed no differences when compared to an unidentified species of surface velvet worm from the same island, thus supporting cave and surface populations belong to the same species. Based on the 16S rRNA data, the Galapagos velvet worms derived from an Ecuadorian/Colombian clade, as would be expected of ease of dispersal from the nearest mainland to the Galapagos Islands.

Highlights

The Onychophora, or velvet worms, are considered “living fossils” and among the most interesting groups of animals for evolutionary biologists
This study is part of a larger project focused on cave mapping, geological investigations and cataloging biological resources of lava tube caves in the Galapagos (Taylor et al 2012)
Velvet worms found inside the cave were darkly pigmented, had eyes, and showed no apparent troglomorphic features (Fig. 2)

Summary

Introduction

The Onychophora, or velvet worms, are considered “living fossils” and among the most interesting groups of animals for evolutionary biologists. Fossils dating back to 540 million years show an overall anatomy which has remained largely unchanged. Modern velvet worms are classified into two families, Peripatidae and Peripatopsidae. The early diversification of these groups pre-dates the break-up of Pangaea, maintaining regionalization even in landmasses that have remained contiguous throughout the history of the groups (Murienne et al 2014). The species of the Peripatopsidae are typically found in southern latitudes and show a classic Gondwanan distribution; Australia, New Guinea, Chile, South Africa, and New Zealand. The Peripatidae have a more equatorial distribution and are restricted to the Neotropics, the Antilles, West Africa, and areas of South-East Asia (Oliveira et al 2013)

Objectives

Methods

Results

Conclusion