Snail tales continued …

So far so good. It’s February, and we’re on to Blog 2. I’m going to continue on the current theme of marine gastropods, moving on to a second piece that my master’s student Stephen completed. Stephen has just completed his masters, which warrants discussion itself, but more on that another time!

Fig. 1. Priabonian age (Ma = millions of years ago)

Stephen’s second paper was accepted in Paleontological Journal, and describes a new species of Paraseraphs from the Priabonian (37.8 – 33.9 Ma; Fig. 1) white limestone formation of Jamaica. Paraseraphs are extinct gastropods, so perhaps you’re wondering why it’s important that this paper was published. Well, really the only way that fossils can be designated to species is morphologically. However, there is a risk in saying that two animals are the same species just because they look the same. In this paper, while we used morphology, we also looked at the spatial and temporal distribution of the species in relation to others.

The description of Paraseraphs cantamessae is based on morphology (Fig. 2). It has a slender shell with slightly concave whorls, and there is distinct elongation of the shell on later whorls. The base of the shell is anteriorly quadrate. The shell spire is acute and the sutures are well defined. While it occurred sympatrically with another species, P. procerum, P. cantamessae is cylindrically elongated, larger, and more dorsoventrally convex. Two additional species occurs in the region. However, they are separated temporally from P. cantamessae. Both P. texanopsis and P. erratica occurred roughly 47.8 - 41.2 Ma (Lutetian). Several other species are morphologically similar to P. cantamessae, but they are separated both spatially (P. armoricensis and P. propedistortum occurred in Europe) and temporally (41.2 – 37.8 Ma and 47.8 - 41.2 Ma, respectively).

Fig. 2. Type material for Paraseraphs cantamessa sp. nov.: (a) holotype USNM, no. 135097A; (b) paratype USNM, no. 135097B; (c) paratype USNM, no. 135097C. (Details and image taken from publication: Maxwell et al. 2018)

So, there you have it. Hopefully you now know even more than you did from the last blog. I think one of the most important lessons out of this paper is that we shouldn’t just think that one species conception is the answer to everything. If we just used morphology in this instance, all the fossils might be considered one species. However, if we take into account other factors, like spatial or temporal distributions, we can begin to see that things might be a little more complicated than they originally appeared. By taking a look at the organism in context, we gain a greater understanding about how it lived in relation to other organisms. 

You can read more about my research in my publications, listed on my blog. You can also find me on ResearchGate, the James CookUniversity website and Twitter.