Posted: Oct 27 2006

 Marshallora modesta (C.B. Adams, 1850) vs Marshallora nichupte Rolán & Cruz-Ábrego, 1995

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 or M. nigrocincta.

M. modesta and M. nichupte are very,

very similar in overall features. 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.

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 adjacent

comparison images illustrate.