Neohelix lioderma derived long after their freshwater ancestor in the Carboniferous era (Solem 1985). This split occurred when these snails lost the function of the body whorl, so that they could get more space within the shell for retraction.

        In the late Paleozoic, five families emerged from the Stylommatophora. From the five families, three orders were formed. The first land snail was found in Westphalian B of Euroamerica ( Solem 1985). These snails sought for land because there was better litter for the snails to live in.

            By the Pennsylvanian era, the Stylommatophora had evolved and split into their orders and families (Solem 1985). At this point, the Stylommaophrans had primitive structures and so they were related to the Athoracophoridae (1985).

            One adaptation that Neohelix lioderma and other Pulmonates developed was the lack of an operculum as adults to seal from any sort of danger, but in the larval stages they do have it (Solem 1985). Instead of using an operculum, Neohelix lioderma uses a rock or an object with calcareous mucus with calcium deposits as a substitution for sealing themselves into their shells (1985). They do this to cope with dry periods in the area.

This is an example of a snail using an operculum to close off the shell. Used with permission of Mei Lin

            Another adaptation that this snail learned is having viable populations in very small ranges by picking the “perfect” spot to live. One place that Pulmonates are found in is on the edge of dry areas. Species keep thriving on the outskirts of these dry areas because there is high diversity in species (Solem, 1985). There are also changes in plant communities that snails feed and live off of and keep their population growing (1985).

           Pulmonates became so diverse and eventually created Neohelix lioderma species because of three factors. One factor is that each species have a very small range so they adapt only to the Red River Valley Region (Solem 1985). Another factor to the diversity is that there is allopatric speciation patterns between each species, which suggests that new species are coming from the division of the ancestral species that are geographically isolated into other populations that evolve (Hickman et. al. 2012). So each species were once one specie but due to either geographic change or emigration, the populations were isolated from each other causing the prevention of genetic interchange (Solem 1985). The third factor is the plant communities within each range. Some plants could be restricted which can cause the snails to stay in that certain area and isolating themselves from other species, becoming more diverse from one another (1985).






Let's see what and how the Tulsa Whitelip eats. Nutrition is next.

I want to go home