Unravelling WA’s “very strange” slug mysteries

WA is globally renowned for its plants and animals diversity. Yet there’s 1 type that’s conscionable arsenic divers but acold little understood: marine slugs.

For almost 80 years, nan Onchidiidae marine slug family was a taxonomist’s nightmare.

Taxonomists are nan scientists tasked pinch studying and classifying each life connected Earth. (No large deal!)

Throughout nan 1800s, things were booming for mollusc experts. Several enterprising taxonomists had discovered and classified slugs into nan Onchidiidae family. 

By nan mid-1930s, activity fundamentally ceased. Then 80 years of silence.

A SLUGGISH EFFORT

Most type had been described based connected preserved specimens from agelong ago. 

It became intolerable to find accusation connected nan colour and style of surviving creatures, and preserved samples were limited.

The situation was excessively big, truthful taxonomists moved connected to different things.

But Pennsylvania State University Associate Professor Benoît Dayrat took up nan challenge.

Caption: Benoît Dayrat is connected a quest to picture nan world’s mysterious marine slugs
Credit: Supplied Benoît Dayrat

PUTTING SLUGS ON THE MAP

For nan past 2 decades, Benoît has been connected a ngo to study much astir nan mysterious Onchidiidae.

He has hopped crossed nan Indo-West Pacific to locate, place and categorize their biodiversity.

“I studied them everyplace from South Africa each nan measurement to Hawaii and Indonesia, nan Philippines, India and besides successful Australia,” says Benoît. 

Benoît’s activity has uncovered a expansive postulation of marine slugs.

Despite years of exploring and plucking nan palm-sized slugs from mangroves and formation rocks, 1 area connected his representation remained blank.

“Somehow I ne'er sewage to Western Australia,” says Benoît.

WA BECKONS

In 2025, Benoît is visiting Curtin University and moving alongside marine intelligence and Adjunct Professor Fred Wells to archive WA’s oversea slugs.

Fred worked for nan WA Museum for much than 40 years and utilized to cod these slugs from nan Pilbara and Kimberley coastlines.

Fred says unluckily location wasn’t capable clip to study them. They remained enigmatic.

“We’re fortunate to person Benoît retired present moving connected this group that we cognize virtually thing astir successful WA,” says Fred.

SLUGGED

The slugs of Onchidiidae lucifer nan ones you mightiness find successful your garden, but they’re chiefly recovered successful marine environments.

Most measurement little than 5 centimetres, and they’re a small rounder and flatter than plot slugs.

Despite their mini size, Benoît says they are akin to 1 of nan world’s biggest creatures.

“The very unusual point is that they are for illustration whales – for nan elemental logic that they respire air,” says Benoît. 

Like whales, nan slugs request oxygen to survive. Physiologically, this makes them different successful position of their behaviour and ecology.

NEW WA SPECIES UNCOVERED

Having collected specimens from Carnarvon to Broome, Benoît has begun to overgarment a clearer image of WA’s slugs.

While they’re easy to collect, it’s harder to find type without bringing them backmost to nan lab.

“We person beautiful broad integrative ways of studying them wherever we do DNA analysis. We look astatine nan anatomy,” says Benoît. 

“After that research, we’ll person a very bully thought of really galore type we have, wherever they are distributed and truthful on.”

Caption: A caller type of slug, from nan Peronia genus, discovered successful Western Australia – this specimen is astir 5cm long.
Credit: Benoît Dayrat.

He notes that respective caller type person been identified, possibly 3 from WA.

Slowly, nan mysteries of nan onchidiids are being revealed, which is key.

“Getting nan basal taxonomy correct allows you to create a image of really they fresh into nan ecosystem,” says Fred.

Unfortunately, basal taxonomy is getting harder to perform.

A CRISIS ON A CRISIS ON A CRISIS

The marine slugs Benoît and Fred person described are not nether imminent threat of extinction. 

However, respective crises frighten our expertise to understand and protect them and nan environments they inhabit.

The ambiance alteration situation is one. Extreme biodiversity nonaccomplishment is another.

The biodiversity situation is compounded by a 3rd situation occurring successful taxonomy.

Last year, a New York Times article by botanist Robert Langellier suggested nan section is dying a “slow death”. 

Investment into training taxonomists has been dwindling for years, including successful Australia.

It’s a awesome interest because taxonomy underpins conservation.

“A CRITICAL SITUATION”

Without taxonomists, type will go extinct earlier we person a chance to observe and picture them, their habitats and their impacts connected ecosystems. 

“We’re successful a captious business successful position of our knowledge of nan type that are coming successful Australia,” says Fred. 

“If we don’t person that taxonomic knowledge and nan group that create it, it makes it very difficult to negociate nan systems.”

To capable nan gaps successful expertise, scientists writing successful nan technological diary Nature successful February 2024 suggested expanding training crossed “technologies specified arsenic integer and virtual reality herbaria, wildlife camera traps and biology DNA analysis” and leaning connected artificial intelligence to assistance type identification.

Time will tell.