A few months ago, science gave this rare lizard a name – and it may already be headed for extinction


Australian Museum

Jodi Rowley, Australian Museum

This article is part of Flora, Fauna, Fire, a special project by The Conversation that tracks the recovery of Australia’s native plants and animals after last summer’s bushfire tragedy. Explore the project here and read more articles here.


Bushfires are a threat to most animal species. But for one rare lizard living on a rocky island in the sky, a single blaze could wipe the species off the planet.

The Kaputar rock skink (Egernia roomi) is thought to have have one of the smallest ranges of any reptile in New South Wales – at the summit of a single extinct volcano, Mount Kaputar.

The existence of this mysterious skink was informally known for decades, and in August last year the species was finally scientifically described. But months later, it may already be headed for extinction.

Late last year, bushfires are thought to have ripped through more than half the Kaputar rock skink’s habitat. We don’t yet know what this means for its survival, but the outlook is not good.

The fire in Kaputar National Park that tore through the skink’s habitat.
Narrabri Rural Fire Brigade

A very special skink

The Kaputar rock skink is handsome lizard, typically around 10 centimetres in body length, with dark chocolate brown and grey scales and an orange belly.

It’s found in the Nandewar Ranges near Narrabri. The ranges – weathered remnants of ancient volcanic eruptions between 21 and 17 million years ago – rise out of the surrounding plains in a series of breathtaking rock formations.




Read more:
Double trouble: this plucky little fish survived Black Summer, but there’s worse to come


The Kaputar rock skink lives on one of these outcrops, Mount Kaputar. It exists on a narrow band of rock at the summit, more than 1,300 metres above sea level.

This high elevation areas is cooler than the surrounding plains, which suits this cool-adapted species perfectly. But the species’ tiny range means it’s highly vulnerable. When danger strikes, the Kaputar rock skink has nowhere to go.

The skink lives at the highest point of Mount Kaputar.
Jodi Rowley, Author provided

When the fires hit

Bushfires tore through the Nandewar Ranges in October and November last year, reportedly burning more than 17,000 hectares of bush. More than half of Kaputar rock skink habitat is believed to have burned.

The expert panel advising the federal government on bushfire recovery has named the skink as one of 119 severely-affected species needing urgent conservation intervention. But the species’ rugged, remote habitat, combined with COVID-19 restrictions, have delayed efforts to assess the extent of the damage.




Read more:
After the bushfires, we helped choose the animals and plants in most need. Here’s how we did it


It’s likely that many Kaputar rock skinks died during the fires themselves, although we hope others survived by crawling deep into rock cracks.

But after the fires, threats remain. Vegetation loss may make the skinks easy prey, and in a charred landscape, there may be little for the reptiles to eat.

History tells us fires do affect high-elevation skinks. For example, fire is thought to have driven the rock-dwelling Guthega skink (Liopholis guthega) to become locally extinct at some sites on the Bogong High Plains in northeast Victoria.

A mountain of threats

Species restricted to a small area are vulnerable to any loss of habitat. And fire is not the only threat to the Kaputar rock skink.

Climate change is a big concern. While many species respond to increasing temperatures by migrating uphill to cooler climes, that’s not possible for the skink, which is already precariously perched on a summit.




Read more:
Sure, save furry animals after the bushfires – but our river creatures are suffering too


Introduced goats may also be taking a toll as they trample through the rocky terrain.

Evidence suggests humans are also a disturbance to the Kaputar rock skink’s habitat. The reptiles live close to the edge of cliff lines that are readily accessible by walking tracks. Trampling of low vegetation has been observed at many sites, as have disturbed rocks – the latter possibly from people wanting to find and photograph the species.

The Kaputar rock skink’s tiny habitat was badly affected by fire.
Mark Eldridge, Author provided

Where to now?

Scientists know relatively little about the Kaputar rock skink. One thing we’re sure of, though, is that the species’ existence is threatened.

Surveys are needed at known skink locations, as well as surrounding areas where it might lie undiscovered. Understanding where the species occurs and how it responds to fires, drought and other disturbances is critical to conservation efforts.




Read more:
Our field cameras melted in the bushfires. When we opened them, the results were startling


Of course it’s the middle of winter now, so the skinks may not be very active on their cold mountain top. But my colleagues and I hope to travel to Mount Kaputar soon to survey the skink’s habitat and find out how the species fared.

It’s just months since science officially welcomed the Kaputar rock skink to the world. It’s far too early to say goodbye.

Dane Trembath, an Australian Museum biologist with a focus on reptiles, contributed to this article.

The Conversation

Jodi Rowley, Curator, Amphibian & Reptile Conservation Biology, Australian Museum

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Why we’re not giving up the search for mainland Australia’s ‘first extinct lizard’



A grassland earless dragon at Jerrabomberra, NSW, November 1991. The search is now on for this species’ Victorian cousin.
CSIRO/Wikimedia Commons, CC BY

Jane Melville, Museums Victoria

You may have seen news in recent days of the suspected demise of the Victorian grassland earless dragon – now thought to be the first lizard species to be driven to extinction by humans in mainland Australia.

That suspicion arose on the basis of a newly published study in Royal Society Open Science by our research team, in which we discovered that the grassland earless dragons of southeastern Australia are not a single species, but four distinct ones: one that lives around Canberra, two in New South Wales, and one restricted to the Melbourne region.

The most recent confident sighting of the Melbourne species was 50 years ago, in 1969 – hence the fears that the Victorian species has already succumbed.

But despite this worrying news, we’re not leaving this lizard for dead just yet. Conservationists are now combing remaining grassland around Melbourne in a search for survivors.




Read more:
EcoCheck: Victoria’s flower-strewn western plains could be swamped by development


Although no lizard species have previously been declared extinct on the Australian mainland, the grassland earless dragons (Tympanocryptis) of southeastern Australia have long been the subject of conservation concern. Even before being split into four separate species, they were already officially listed as endangered.

The Victorian grassland earless dragon (Tympanocryptis pinguicolla) is known only to occur in the native grasslands around Melbourne. A review of historical collections at Museums Victoria show that it was found at several locations including Sunbury, Maribyrnong River (then called “Saltwater River”), and as far west as the Geelong area until the late 1960s.

Although there is little information available about the ecology of this species, it was described by Lucas and Frost in 1894 as:

Inhabiting stony plains and retreating into small holes, like those of the ‘Trap-door Spider,’ in the ground when alarmed […] Often met with under loose basalt boulders.

The last confirmed sighting was near Geelong in July 1969.

First mainland extinction?

Globally, 31 reptiles have been listed as extinct or extinct in the wild, according to the IUCN Red List, the global authority on the status of species. Two skinks and one gecko species have been declared extinct in the wild on Christmas Island, a remote Australian territory in the Indian Ocean. But until now there have been no recorded reptile extinctions on the Australian mainland.

Yet it is too early to give up on the Australian grassland earless dragon. Zoos Victoria researchers have completed a mapping analysis of potential grassland habitats. But this doesn’t give us enough information to say whether or not any grassland earless dragons remain.

There are several factors that leave open the possibility that the Victorian grassland earless dragon is still clinging to survival. There are some remaining habitat areas that have not yet been surveyed, and this species is small, secretive and hard to find. We urgently need more surveys to try and find any remaining populations.




Read more:
Vale ‘Gump’, the last known Christmas Island Forest Skink


If these lizards are not yet extinct, their protection will clearly become an urgent conservation priority. But it is hard to develop a conservation program without knowing where the target species actually lives, or indeed whether it is still alive at all.

Zoos Victoria is now leading a campaign, alongside expert ecologists and local communities, to try and confirm the presence or absence of the Victorian grassland earless dragon. This involves various methods, including habitat mapping, camera trapping, and active searching. The team is also working to identify unsurveyed areas that might potentially be home to these elusive lizards.

Last year the team deployed a series of small pitfall traps at two locations in Little River. Unfortunately, no earless dragons were detected during the survey and few lizards of any species were caught, despite the fact that these locations seemed to offer appropriate food and habitat.

The team is not giving up yet and is committed to continuing the search, with Zoos Victoria researchers having identified sites with suitable habitat both within and outside of the historical distribution, which they aim to survey intensively over the coming years. Meanwhile, reptile keepers at Zoos Victoria are developing husbandry techniques to help look after the grassland earless dragon species from Canberra and NSW.

The conservation challenge has got harder, because where previously we were tasked with looking after one species, we now have to safeguard at least three – and hopefully four!


This article is based on a blog post that originally appeared here. It was coauthored by Adam Lee and Deon Gilbert of Zoos Victoria.The Conversation

Jane Melville, Senior Curator, Terrestrial Vertebrates, Museums Victoria

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The first known case of eggs plus live birth from one pregnancy in a tiny lizard


Melanie Laird, University of Otago and Camilla Whittington, University of Sydney

For most animals, reproduction is straightforward: some species lay eggs, while others give birth to live babies.

But our recent research uncovered a fascinating mix between the two modes of reproduction. In an Australian skink, we observed the first example of both egg-laying and live-bearing within a single litter for any backboned animal.

This suggests some lizards can “hedge their bets” reproductively, taking a punt on both eggs and live-born babies to improve overall survival chances for offspring.




Read more:
Ancient fossil fills a 75 million-year gap and rewrites lizard and snake history


Making reproductive leaps

Most vertebrate species (animals with a backbone) fall neatly into one of two distinctly different reproductive categories.

Oviparous species are egg-layers. These eggs may undergo external fertilisation – such as in spawning fish – or are fertilised and shelled internally, like those of reptiles and birds. Oviparous embryos rely on egg yolk as a source of nutrition to continue development until hatching.

In contrast, viviparous species are live bearers that carry their young to term. Some live-bearing species, including humans, support embryonic development internally via a placenta. Egg-laying is ancestral, meaning that modern live-bearers have descended from egg-laying ancestors.

Physiologically, the evolution of live birth from egg-laying is no mean feat. This transition requires a whole suite of changes, sometimes including the evolution of a placenta – an entirely new specialist organ – as well as loss of the hard outer eggshell, and keeping the embryo inside the body for a longer time.

The placenta is a highly complex organ. One of its jobs is to transfer nutrition to the developing baby.
from www.shutterstock.com

Despite these complex steps, reptiles, particularly snakes and lizards, appear to be unusually predisposed to making the leap to live birth. This capacity has evolved in at least 115 groups of reptiles independently.




Read more:
A hidden toll: Australia’s cats kill almost 650 million reptiles a year


Having it both ways

It’s easy to see why reptiles, as a group, are fascinating models for studying how live birth evolves from egg-laying.

Of particular interest are two Australian skinks that have both live-bearing and egg-laying individuals (known as being bimodally reproductive). These lizards are incredibly valuable to evolutionary biologists as they offer a snapshot into evolutionary processes in action.

The three-toed skink Saiphos equalis is one such species. Reproduction in S. equalis varies geographically: populations around Sydney lay eggs, while those further north give birth to live young.

Whether individuals are live-bearing or egg-laying seems to be genetically determined: when researchers swap their environmental conditions (by moving them from one site to another), the females retain their original reproductive strategy.




Read more:
Lizards help us find out which came first: the baby or the egg?


Mothers know best

Our latest research shows this lizard is intriguing in another completely unexpected way.

We observed a live-bearing female that laid three eggs, and then gave birth to a living baby from the same litter weeks later. We incubated two of the eggs, one of which hatched to produce a healthy baby.

A live-bearing female S. equalis in our laboratory colony laid three eggs, one of which hatched to produce a healthy baby.
Camilla Whittington

This finding is remarkable for two reasons. First, as far as we are aware, this is the first example of both egg-laying and live birth within a single litter for any vertebrate.

Second, in some cases, individuals may be capable of “switching” between reproductive modes. In other words, as laying eggs and giving birth each come with their own advantages and disadvantages, individuals may be able to “choose” which option best suits the current situation.

Closer look at eggshells

To better understand this reproductive phenomenon, we investigated the structure of the egg coverings of these unusual embryos in minute detail (using an advanced technology called scanning electron microscopy).

We found that in this litter, the egg-coverings were thinner than those of normal egg-laying skinks and had structural characteristics that overlapped with those of both egg-layers and live-bearers (which have thinner coverings that are greatly reduced).

Egg coverings of S. equalis consist of an outer crust (C) and an inner shell membrane (SM). We compared the structure and thicknesses of these layers of both egg-laying (A) and live-bearing (B) S. equalis to identify similarities with our ‘unusual’ embryos (C).
Melanie Laird

How evolution works

We still don’t know the trigger that caused this female to lay eggs and give birth to a live baby from the same pregnancy.

However, our findings suggest that species “in transition” between egg-laying and live bearing may hedge their bets reproductively before a true transition to live birth evolves.

Being able to switch between reproductive modes may be advantageous, particularly in changing or uncertain environments.

The three-toed skink lives in eastern Australia.
Doug Beckers / flickr, CC BY

For example, extreme cold, drought or the presence of predators can be risky for vulnerable eggs exposed to the environment, meaning that mothers that can carry offspring to term may have the upper hand.

In contrast, lengthy pregnancies can be taxing on the mother, so depositing offspring earlier as an egg may be beneficial in some situations.

We suggest that other species in which live birth has evolved from egg-laying relatively recently may also use flexible reproductive tactics.

Further research into this small Australian lizard, which seems to occupy the grey area between live birth and egg-laying, will help us determine how and why species make major reproductive leaps.




Read more:
Curious Kids: why do hens still lay eggs when they don’t have a mate?


The Conversation


Melanie Laird, Postdoctoral Fellow, University of Otago and Camilla Whittington, Senior lecturer, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Australia: The Moloch


The link below is to an article that takes a look at the Moloch (Thorny Devil) of Australia.

For more visit:
http://inhabitat.com/the-biomimicry-manual-what-can-a-thorny-devil-teach-us-about-water-harvesting/

Madagascar: ‘Moby Dick’ Mermaid Lizard


The link below is to an article reporting on the discovery of what has been called the ‘Moby Dick’ Mermaid Lizard in Madagascar.

For more visit:
http://news.mongabay.com/2013/0116-moby-dick-mermaid-lizard.html

Madagascar: Moby Dick Mermaid Lizard Discovered


The link below is to an article that reports on the discovery of a new underground lizard in Madagascar, Africa.

For more visit:
http://news.mongabay.com/2013/0116-moby-dick-mermaid-lizard.html

Article: Democratic Republic of Congo – New Lizard Discovered


The following link is to an article reporting on a new species of lizard discovered in the Democratic Republic of Congo – Cordylus marunguensi.

For more visit:
http://news.mongabay.com/2012/0521-hance-cordylus-marunguensis.html