Three new chameleon species from Madagascar

Madagascar is famous for the immense diversity of animals that are found nowhere else in the world. Among its most famous animals number the chameleons: both the largest (Parson’s chameleon, Calumma parsonii, or Oustalet’s chameleon, Furcifer oustaleti, depending on how you define “large”) and smallest (the dwarf leaf chameleon, Brookesia micra) chameleons are native to Madagascar. In fact, about half of the over 200 species of chameleons are strictly Malagasy.

The number of species known to science is quite steadily increasing; four new species were described in 2017 alone. Yet many chameleons are highly threatened, such as the Tarzan chameleon (C. tarzan) from a dwindling forest fragment in eastern Madagascar.

In April 2018, three more species were described from Madagascar in the Zoological Journal of the Linnean Society—and they are stunning.

Uetz’s soft-nosed chameleon, Calumma uetzi

Uetz’s soft-nose chameleon easily numbers among the most beautiful of Madagascar’s chameleons. Displaying males turn bright yellow along their sides with stripes of pink and purple, and a variety of colours on the head, from teal to aquamarine, yellow, salmon, and purple, with a black stripe running through the eye. Unimpressed, a female turns dark brown, almost black, with brightly contrasting yellow spots on her head that convey her vexation with his attentions.

This species was discovered on the Sorata massif in northern Madagascar during an expedition by some of the authors of the study in 2012. These remote forests are extremely poorly studied, and under extreme anthropogenic pressure, so that this species, although only just described, is probably endangered.

The species was named after Peter Uetz, who maintains the Reptile Database—an invaluable tool for researchers working on reptiles anywhere in the world.

Spear-nosed soft-nosed chameleon, Calumma lefona

In general, it is good to have a number of specimens when describing new species, but sometimes, despite best efforts, this is simply impossible. In these cases, variation within a species cannot be understood, but at least a characterisation of some of the morphology and genetic distinction can be done, and a species can still be described.

This was the case with one of the newly described chameleons, Calumma lefona: a single specimen was collected from northern Madagascar in 2010 that turned out to be a new species. This is evident from its genetic differentiation, but also from the shape of the skin flap protruding from its nose, the so-called “rostral appendage.” In this species, the appendage is long and pointed, and so it was named “lefona,” the Malagasy word for spear.

This spear-nosed chameleon is remarkable in another, less obvious way though: micro-CT scans revealed that there is a large, round hole in the roof of its skull. This kind of hole was already known from some related chameleons, but C. lefona has the largest. This hole sits right on top of the brain, and although its function is not yet clear, it might be involved in the internal clock of the chameleons, or in helping them thermoregulate.

Julia’s soft-nosed chameleon, Calumma juliae

The third species described in this new study was a small, unassuming, largely brown chameleon with bluish spots on its head. This new species, dubbed Calumma juliae after one of the people who helped discover it, is a relict of a lost age, and may be the most threatened chameleon in the world.

Curiously, this new species is closely related to another species from northwestern Madagascar—a species from which it is separated by some 400 km. It is a relict of what used to be large and extensive forests connecting these areas. Deforestation has ravaged Madagascar, leaving tiny islands of forest in some places that can be the last few square metres of once vast swathes.

One such small forest—calling it a copse would be more accurate—lies on the edge of one of Madagascar’s busiest roads, just outside the town of Moramanga. But this tiny fragment of forest is the only place where Julia’s soft-nosed chameleon is known to occur. To put it in perspective, a generously drawn perimeter of the forest is under 2 km in length; an area of 15 hectares. It is surrounded on all sides by rice paddies and invasive eucalyptus, and just last year, a piece of the forest was burned off. To put it bluntly, the species is in dire straits.

Over repeated searches for this chameleon over several years, a number of individuals were found, but every one of them was female. This problem is remarkably widespread in chameleons, and several species have been known only from females for long periods before a single male was ever found. Still, it raises serious concerns; captive breeding of chameleons is always tricky, but in this, perhaps the most threatened chameleon of all, no breeding projects could be started until males can be found.

Featured image credit: “When a male Calumma uetzi (left) meets an unreceptive female (right), the mood can quickly get aggressive. While the male puts on a show of colour, the female darkens and develops brightly contrasting patterns on her head, threatening the male with open mouth.” Copyright: Frank Glaw (ZSM/LMU). Used with permission.