Höhlentauchen / Cave Diving / Buceo en Cueva Riviera Maya
I have WhatsApp +52-9841312934

Posts Tagged fresh water

Short Finned or Common Molly

Short Finned or Common Molly

Molly is another name for the fish of the gender Poecilia. They can be found in many cenotes of the Riviera Maya and feed from algae and small crustaceans that live in the freshwater of the cenotes

“In this genus we find several in vertebrates completely untypical characteristics: … Thirdly, specimens of especially this species are extremely variable, in coloration as well as in body shape. For example, one often finds … the phenomenon of the “early” and “late” (in terms of sexual maturity) males in this species.”

(all Livebearers and Halfbeaks, Michael Kempkes, Dipl. Biol. Frank Schäfer, p. 21 f.)

The many variations in colouring and body shape has made this fish very popular in aquaristics. There are many cultivated species and even specialists only agree that they disagree about the correct systematology (page 22, as above).

“Early” and “late” males means that sexual maturity is not dependent on a specific age or size, there are males that mature very early and from then on do not grow a lot anymore and there are significantly bigger specimens.

Originally I identified the pictured species as Poecilia sphenops, however, comparing pictures of a photographer (and freshwater fish expert) that has been the same day at the cenote has shown that this is Poecilia orri (the mangroves molly). I would not have found that out based on environment as there are no mangroves in this cenote and the halocline between fresh and saltwater starts only at 16 m way back in the dark areas of this cave system. The picture displays a female on the left side and a male on the right.