Phormictopus are the largest tarantulas of the Caribbean. Maria Gombasne Gudenus et al have tackled Phormictopus taxonomy at an advanced hobbyist level. In July 2016 they published their findings in the Journal of the BTS (pdf). They begin by distinguishing Cuban from non-Cuban Phormictopus:
“These two groups have a clear separation with regards to visible attributes related to colour, size and habitus (body build). The offspring of the two groups also have different colours. While Cuban species have brownish young, those found outside Cuba are bluish.”
The best known Cuban Phormictopus is Phormictopus auratus; outside Cuba, Phormictopus cancerides (Hispaniola: Haiti and the Dominican Republic). In the past several years the Dominican Republic has yielded a number of lineages with varying shades of brown, purple, green, and blue. Spermathecae examination by the Gudenuses suggests species differences between various groups as well as between these groups and P. cancerides.
Here we offer another possible distinct species, contributed by Markus Ruhnau. The male and female in the photo above were collected within meters of each other near Salinas, a town on the southern coast of the Dominican Republic.
Spiderlings and above photo courtesy Markus Ruhnau.