Chitons Down Under

Senckenberg PhD student Kasia Vončina recently journeyed to Australia to explore chiton collections and collect specimens for her fascinating research on these unique marine molluscs.

What Are Chitons?

Chitons are marine molluscs with a distinct twist on the typical mollusc shell. Instead of a spiral shell like a snail or cone-shaped shell like a limpet, chitons have eight separate shell plates. This arrangement allows them to roll into a protective ball when dislodged and flexibly adapt their shape to cling to irregular surfaces like rocks. These shell plates can feature stunning colors and intricate patterns, causing many chitons to seemingly bedazzle their otherwise unimpressive environment of algae covered rocks and other hard surfaces. Others are especially great at camouflage and blend in seamlessly with their surroundings.

Whether in bright colors or classy neutrals, chiton shell plates have another feature: pores! Okay, maybe not that exciting initially, but these tiny holes open to a complex sensory system embedded in chiton shells! This intricate canals system together with the pores are called “aesthetes” and they’re present in all chitons. Moreover, some chitons even have more elaborated version of this system, i.e. shell eyes, allowing the chiton to form images!

Kasia’s Research

Kasia’s work focuses on understanding the evolutionary history of the Acanthochitonidae family, a diverse group of chitons that includes 11 genera and about 170 species. She is working to piece together the scientific version of a chiton family tree, gathering morphological and molecular data from these species. Her recent trip to Australia was aimed at collecting chiton specimens, exploring museum specimens, and attending a mollusc-focused conference.

Collecting Chitons in the Field

While in Australia, Kasia looked for Acanthochitonidae species, which are known for their needle-like structures on the girdle (the soft tissue around the shell plates) and tufts of spicules surrounding their shells. Most species in this family inhabit intertidal rocky pools, so Kasia spent hours flipping rocks at low tide. Some species, however, are found deeper in the sea, living together with sponges or even acting as ambush predators.

Kasia focused on intertidal species, turning over hundreds of rocks during her fieldwork. Once she located a chiton, she carefully pried it from its rocky home and stored it in a specimen jar for further study.

Exploring Museum Collections

In addition to field sampling, Kasia visited three Australian museums: Museums Victoria in Melbourne, the South Australian Museum in Adelaide, and the Western Australian Museum in Perth. These visits took her behind the scenes to access extensive scientific collections of preserved specimens.

Her primary focus was photographing type specimens—the animals on which the original taxonomic description for that species was based on. These specimens are crucial in taxonomy, serving as reference points for identifying and classifying other specimens.  If you don’t know what the type specimen looks like, how can you be sure of which species you’re actually studying? Kasia also collected tissue samples from well-identified specimens in the collections, which she’ll use for genetic analysis and comparisons with her freshly collected material.

Molluscs on the Edge Conference

Kasia capped off her trip by attending the Malacological Society of Australasia’s triennial conference, “Molluscs on the Edge,” in Perth. She presented her research on “Phylogenetic insights into Cryptoplacoidea H. Adams & A. Adams, 1858 (Mollusca: Polyplacophora) using a target enrichment approach,” earning second place for her talk! The conference provided a fantastic opportunity for collaboration, with many attendees offering to collect chitons for her research.

Special thanks go to the conference’s organizing committee for their excellent work!

Acknowledgments

Kasia’s Australian fieldwork was partially funded by the American Malacological Society and the Conchologists of America, while her conference attendance was supported by a travel grant from the Malacological Society of Australasia. She extends heartfelt thanks to Audrey Falconer and Leon Altoff for their help collecting chitons in Victoria and capturing stunning photos of live specimens, as well as to Henry Carrick for his assistance in Western Australia and for help with finding Cryptoplax (Instagram link).

Kasia’s research offers new insights into the fascinating world of chitons and highlights the importance of both fieldwork and museum collections in understanding biodiversity and evolution.

Check out the photos below of Kasia’s Australian chiton adventure:

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Kasia Vončina
Ricketts Point Marine Sanctuary, Victoria during the low tide. Kasia found a lot of Acanthochitona retrojecta in this location.
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Kasia Vončina
Acanthochitona retrojecta from Ricketts Point Marine Sanctuary, Victoria.
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Kasia Vončina
Galeolaria is a genus of coastal tube-building annelid fanworms – and also a habitat in which we found most of Acanthochitona retrojecta specimens.
Barwon Bluff Marine Sanctuary, Victoria. A lot of loose rocks to turn over and check for chitons!
Checking the rocks for chitons.
Ischnochiton (Ischnoradsia) australis from Barwon Bluff Marine Sanctuary. One of the largest and most common chitons in south-east Australia.
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Kitty Miller Bay, Phillip Island, Victoria.
In this muddy locality for the first time in her life, Kasia saw Cryptoplax, a unique chiton species whose shell plates are nearly hidden!
Melbourne skyline from Albert Park.
Kasia worked with the Museums Victoria chiton collection.
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© Leon Altoff. All rights reserved.
Acanthochitona retrojecta collected in Ricketts Point Marine Sanctuary.
Working with the samples and identifying collected chitons in the laboratory of Audrey Falconer and Leon Altoff – leaders of Marine Research Group Victoria. (This is Kasia’s dream home laboratory)
Working with the dry collection of chitons in the South Australian Museum in Adelaide.
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© Henry Carrick
Acanthochitona bednalli from Woodman Point, Western Australia.
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Henry Carrick
Kasia attended the “Molluscs on the Edge” conference in Perth, presenting some research findings from her PhD.
Kasia (left) received the award for second place in the oral presentation student competition. Priscila Salloum (center), president of the MSA and Lisa Kirkendale (right), Head of Aquatic Zoology and Curator of Molluscs at the Western Australian Museum were organizers of the “Molluscs on the Edge” conference which took place in Perth. Photo courtesy of Platon Vafiadis.