What’s in a name? Keeping up to date with the taxonomy of Philippine land snails

What’s in a name? Keeping up to date with the taxonomy of Philippine land snails

The process of collecting and identifying an organism is long and stringent. Despite this, mistakes can still be commonplace. Lorenzo Ravalo is a contractor working with us as a Natural History Technician and takes us through some of the challenges faced in keeping up to date with taxonomy.

Identifying an organism is complex. This is further modulated by the ever-evolving nature of biological classification, where several years’ worth of work can change in an instant when a new study is published.

Added to this, the minor detail that gastropods represent one of the most diverse animal groups and things could get a little bit tricky, especially when closely related snail species are indistinguishable to an untrained eye.

Change one, change them all

Enter Philippine land snails, which are particularly diverse. These groups primarily comprised of seven taxonomic families have gone through several layers of taxonomic revisions since their first identification which leaves a lot of cleaning up for museum staff.

A tray of multi-coloured shells compartmentalised into sections
A drawer full of land snail shells from the Philippines before being databased into our collection and repacked in state-of-the-art boxes. Photo by Jean-Claude Stahl. Te Papa

Take the families Camaenidae and Bradybaenidae, both belonging to the superfamily Helicoidea. These two groups have been alternately considered two distinct families or just a single family, with new developments in molecular methods sometimes pushing things in one direction and sometimes to another.

Two angles of the same shell on a black background
Example of a Camaenidae/Bradybaenidae snail: Cochlostyla portii. Photo by Jean-Claude Stahl. Te Papa (M.248421)

Historical specimens of Philippine Camaenidae and Bradybaenidae in our collection are a mixture of donations from past naturalists and private collectors that we have accumulated through the years – the oldest one was collected in the late 1800s.

Historically, Camaenidae and Bradybaenidae snails were often listed under the umbrella genus Helicostyla. Our evolving understanding of systematics has led to the reclassification of several snail species into other genera (Chrysalis, Dryocochlias, Helicobulinus, etc.), superseding previous combinations.

What does it mean to a museum?

In a museum setting, this involves changing the classification in our database and reprinting labels that correspond to the currently accepted name for the organism in question.

This leaves curators and technicians the arduous task of revising previously catalogued specimens before the taxonomy changes again!

But I hear you say, “Why is this important?”

It’s a matter of understanding the extent of biodiversity an ecosystem has. The Philippines is considered a megadiverse country, with each organism providing a wealth of ecosystem services that contribute to the overall welfare of the environment.

Land snails specifically contribute to soil production and nutrient recycling. Land snails contribute to soil production and nutrient recycling and are therefore responsible for keeping the ecosystem healthy – in Philippine rainforests and elsewhere.

Two angles of the same shell on a black background
The species of the genus Ryssota, like this one R. otaheitana, can be used in local dishes. Photo by Jean-Claude Stahl. Te Papa (M.305800)

On a less technical note, it also helps that these snails are quite tasty and feed a wide range of organisms such as birds, reptiles, arthropods, and humans. The local delicacies Ginataang Kuhol (Snail Stew) and Adobong Kuhol are a must-try!

Understanding the micro helps the macro

To understand the macro implications of biodiversity we must first understand what we have. The existence of these snails maintains the other parts of the system to keep doing their roles as a whole. Like constructing furniture using instructions, keeping tabs on the building blocks of a biome helps us understand what occurs in it as a whole.

It’s even possible that we are underestimating the diversity of land snails in the Philippines but unless we look through the nitty-gritty of it, we will never know!

Keeping up to date with taxonomy is important in museum collections especially in the digital age. The rise of technology has made collections more available than at any other point in history.

In this regard, it is paramount that the information we catalogue is accurate and in tip-top shape. Maintaining these modern naming conventions should not be underestimated. Although Philippine snail taxonomy evolved drastically over a century, you’d be surprised how much it can change in just a year!

Personally, having to sift through the camaenids classified under Helicostyla and finding their updated taxonomy, then linking said updates to the museum database… Let’s just say Helicostyla holds a very special place in my heart now.

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