Colonization of the most isolated island on Earth: What is the origin of the spider Tetragnatha paschae?


Tetragnatha paschae is the only endemic spider of Rapa Nui. The objectives of this research project are: (1) collect and determine the origin of colonization of T. paschae, (2) estimate the feasibility of future studies and (3) built a network of research contacts. The most updated research about spiders corresponds to a publication from 1997 which does not record T. paschae. Related with insects there are only 2 publications. The main activity developed on the island was general collecting of spiders and insects. I also gave a seminar. The objective number (1) couldn’t be achieved because I didn’t find the species. However, I found a lot of specimens which seem to be from another species in the genus, potentially T. nitens. The objectives (2) and (3) were achieved successfully. The main lessons learned are: (1) there is a big need for more faunistic research, (2) there is a variable degree of preservation of natural environments, (3) in the island there are tensions related with the land and they could affect the development of the field work. The samples will be use in the following ways: (1) the specimens of T. nitens will be included in a phylogenetic analysis that is part of my PhD dissertation, (2) the collected spiders and insects will produce two publications with maps of distributions of the organisms, (3) any new specie will be described and (4) we will send back to the island a collection with the identified material for educational and reference purposes. 

Darko Davor Cotoras Viedma
Publication date: 
September 6, 2012
Publication type: 
Student Research