Spidering in Madeira I

On March 26th I begun my journey to Madeira Island. Our goals are several spider genera that have speciated in the Madeira archipelago, for which we intend to perform integrative taxonomic studies, using phylogenetic analyses, geometric morphometics, gut content analyses, etc.

I started with the much helpful Isamberto Silva aiding me in an initial job of finding Dysdera and Hogna specimens. We sampled from Paúl da Serra, Montado dos Pessegueiros, the Central Mountain Range and Ponta de São Lourenço, with relative success (a few endemic Dysdera remain hard to find).

On March 30th Isamberto left me for other duties but I was then joined by Miquel Arnedo and Pedro Oromí, who were coming to setup the first MSS traps (millieu subterranean superficiel, also mesocavernous shallow stratum).


Perhaps the main difficulty of sampling MSS is finding a good spot. It demands a lot of hiking, driving around and perseverance (if you are midway through the hole, find unbreakable bedrock, and have to find a new spot). Eventually, with a good effort, we managed to set the 4 traps available. These are made of a PVC tube with multiple small holes, inserted in a hole, which is then completed with small stones. The trap then gets an inner container with propyleneglycol and is covered with a lid and then dirt. We hope we can find some cryptic species with this method and even something totally new. We will see about that in some time.
As this report from the field is being written, I am about to head to Desertas while Miquel and Pedro are going back to office duties.

by Luis Crespo (text) & Miquel Arnedo (photos)