These small Atyids were collected near shore on overhanging vegetation in the Río Espíritu Santo, Puerto Rico. I believe them to be female Potimirim sp.
Neonshrimp wrote:It is small, is it about 1/2 inch?
That's the approximate length of the females. The much smaller shrimp collected with them (only several millimeters in total length) seem to be males of the same species. One of these is visible on the heater adjustment knob in the second image.
You did not find any Xiphocaris there? Those are my favorite caribbean shrimp. It's probably No. 1 on my list of shrimp with saltwater larvae that I would like to breed in larger numbers once I have my shrimp breeding facility set up in California.
Mustafa wrote:You did not find any Xiphocaris there? Those are my favorite caribbean shrimp. It's probably No. 1 on my list of shrimp with saltwater larvae that I would like to breed in larger numbers once I have my shrimp breeding facility set up in California. :)
They were very abundant at almost every site I visited. Just below Carraizo Dam on the upstream segment of the Río Grande de Loíza, I noted -- amongst innumerable shoals of more gracile specimens -- a few unusually large Xiphocaris in the deeper pools. The most probable explanation for this size disparity, in my view, is that the larger shrimp were simply older; oddly enough, nowhere else did I observe Xiphocaris of such size. Having captured several of both variety, I can try to get some specific measurements later.
At least four: Xiphocaris elongata, one species of probable Potimirim, Palaemon pandaliformis, Macrobrachium faustinum, and numerous unidentifiable juvenile Macrobrachium.
The larger species of Macrobrachium, my primary targets, remained frustratingly elusive (exuvia and fleeting glimpses being all that I saw of them). This is not to say that collecting their smaller congeners amounted to much less of a challenge: though they would readily creep out from amongst rocks to approach a slab of coconut in a stationary net (or nip at sandaled feet), the slightest overhead movement would instantly send them to scurry back to unreachable crevices -- from which most would refuse to extend anything more than their antennae for several minutes. Specimens exposed beneath overturned stone would frequently jet away before the silt had cleared, and wire minnow traps met with little success as well. However, due to the truly precarious nature of most water-access paths, I was not able to do much night collecting, and commercial fishing bait or fresh meat might have brought me greater success during the day.
Mustafa wrote:You did not find any Xiphocaris there? Those are my favorite caribbean shrimp. It's probably No. 1 on my list of shrimp with saltwater larvae that I would like to breed in larger numbers once I have my shrimp breeding facility set up in California.
You probably should contact Mirko Abraham. He recently successful bred some Xiphocaris elongata.
All of the female Potimirim I found in the wild were patterned a deep purple-black with a lighter longitudinal stripe and distinctly blue patches on the uropods. On whitish sand, they've taken on much lighter tones.