Posted: Oct 27 2006

 Marshallora modesta (C.B. Adams, 1850) vs Marshallora nichupte Rolan & Cruz-Abregoo, 1995. And, what about Marshallora nigrocincta (C.B. Adams, 1850)?

This discussion arises from a Triphora collected in Key Largo and sent to Dan Teven in a vial of micros. Dan posted the following comment:

"There was one Triphora in the batch, which appears to be Marshallora modesta. According to Redfern, Triphora nigrocincta (which is what I would've called this shell) may really be a complex of species, of which M. modesta is one. I presume M. nichupte is another, but I still haven't seen a pic or a description."

Marlo: There are several of us collectors here in Florida who agree with the comment cited by Redfern regarding M. nigrocincta. Be that as it may, M. modesta is a clearly defined species very common around Florida often identified as M. nigrocincta. M. nichupte is far less common (as far as I know only documented from the Keys), but since it was named only 11 years ago, it may well be in collections from other Florida locations as M. modesta.

M. modesta and M. nichupte are very,

very similar. And, if you are trying to

identify a less than adult specimen,

there is really only one character to

rely upon to accurately distinguish the

two. The protoconchs are distinctly

different. The protoconch of

M. nichupte has 1.5 - 2 smooth,

bulbose whorls. The protoconch of

M. modesta has 4- 4.5 conical whorls

with those below the nucleus having

two spiral cords in the middle and

axial cords above, in between, and

below. The following comparison

images are the best I can do as of

this moment.