Euplerids: Falanoucs and Fanalokas

Fanaloka

The relationships of the native Madagascan carnivores were uncertain before the advent of genetic testing at the end of the 20th century. The majority were assumed to be mongooses, since that is very much what they looked like, but three species didn't quite fit the pattern. 

Two of these were, so far as anyone could tell from their physical appearance and habits, civets. They were often placed in their own subfamily, reflecting their distance from other civets, but nonetheless, they were thought to belong among the viverrids. Following genetic studies in 2003, however, it became clear that they belonged in the same group as (i.e. shared a unique common ancestor with) the Madagascan "mongooses". Since some of them clearly weren't mongooses, and since they had diverged from the real ones so long ago, the subfamily was split off and promoted to full family level, now including both the mongoose-like and civet-like species.

To avoid confusion, this meant that the civet-like species needed new names. Following the usual modern method for doing such things, scientists simply borrowed the local names for the animals ("civet" comes from Arabic, "mongoose" from Marathi). Thus, the species formerly known simply as the "Malagasy civet" became the fanaloka (Fossa fossana). 

To be fair, the name still isn't universally used, even in sources written this century. Indeed, there are also variants on the name, such as "striped civet" and "spotted fanaloka" - as if there is some non-spotted counterpart to compare it with - the profusion of which may be linked to the animal's relative obscurity outside of its homeland.

The fanaloka is quite a bit larger than any of the vontsiras, although it is also smaller than any living species of civet. Adults reach about 40 to 45 cm (16 to 18 inches) in body length, with the largest males weighing just under 2 kg (about 4 lbs); twice the weight of a vontsira but less than half that of a domestic cat, or of most civets. (Or at least, this is what the few recorded measurements show; they were taken during the dry season when animals may have been underweight.) They have a pale brownish coat, marked with a pair of dark stripes down the back, flanked by a series of increasingly broken lines that eventually peter out into a row of spots.

Despite the smaller size, fanalokas have a body form that resembles that of a civet far more than a mongoose and, for example, they have noticeably shorter tails than vontsiras. They also have anal scent glands, as civets do, although they may use the glands on their face and neck at least as much when scent marking to leave messages for one another. 

They live along the eastern side of Madagascar, where the thickest forests remain. Although they will tolerate a wide range of woodland types (at least, among those found on the island) they prefer areas with plenty of available water, and avoid areas with heavy logging or similar disruption. Where they are found, they can be amongst the most common native carnivores, rivalling the ring-tailed vontsiras with population densities of three individuals per square kilometre (8 per square mile) in the most suitable forests.

They are nocturnal, sleeping through the day in tree hollows or rock crevices in cliffsides and, like most of their close relatives, do not seem especially sociable. One of the few studies on their diet indicated that they primarily feed on aquatic or semi-aquatic animals. Frogs and crabs were the most common large prey animals found in their dung, followed by rodents and swamp-dwelling tenrecs (local, shrew-like mammals). These are accompanied by many invertebrates, including grasshoppers, beetles, and millipedes. However, we are again limited by the small number of studies, since this one was conducted in a particularly damp jungle. Granted, this is where they prefer to live, but they have also been recorded in places with no nearby standing water at all, so they are probably quite willing to eat other foods if they have to.

Their lives are more tuned to the seasons than is often the case in the tropics, due to the presence of a distinct dry season between August and November. (Although, on the humid east coast where fanalokas live, "dry season" is very much a relative term...) During this time, fanalokas store fat in their tails as a reserve, which can comprise as much as a quarter of their total body weight. It's also when they breed, ensuring that the young are born when the rains become heavier again. This results in a single young at a time, born with its eyes open and reasonably active, being able to walk at three days, and weaned by two and a half months.

Falanouc

The other species formerly identified as a civet was split into two in 2010, although the respective forms had been recognised as subspecies since the 1920s. By far the more common of the two is the eastern falanouc (Eupleres goudotii), the species for which the former subfamily was originally named in 1835. 

This lives in much the same area as the fanaloka, and has a similar habitat too, although perhaps with an even greater preference for swampy terrain. They are similar in general form, having the same scent glands and ability to store fat in their tail, but they are slightly larger and notably more muscular, often reaching weights of 2.1 kg (4 lbs 10 oz.). Their coat is a much more uniform reddish-brown colour, lacking spots and only fading on the animal's underparts. 

Their feet are comparatively large and bear strong and powerful claws that reach the ground when they are walking. One might think that this would be because they are aggressive predators, tearing at the flesh of their victims, but they aren't. This becomes apparent when one looks at their teeth, which, unlike the claws, are unusually small and lack the shearing surfaces required to slice tough meat. 

In fact, the few studies of their diet indicate that they eat little but earthworms, although supplemented by other invertebrates and probable carrion from small reptiles and the like. There are also some anecdotal reports that they consume fruit. In short, they are carnivores that have adapted to soft-bodied, defenceless prey. The claws are most likely there to dig into the soil in search of food, although they can use them defensively if they have to. While they presumably could also dig at least shallow burrows, they don't, instead sleeping in tree hollows. Having said which, while younger individuals can climb trees to find shelter, fully grown adults either can't or won't, selecting hollows at the base of tree trunks rather than those higher up.

The few observations of falanoucs in the wild suggest that they can be active at any time of day or night, with little obvious preference for either. While they can fight in self-defence, if they do spot a threat, they are more likely to simply freeze in place, remaining motionless for up to an hour. They have generally only been seen alone, and so are likely antisocial outside the breeding season, and they seem to make few noises, communicating a desire to mate by leaving scent marks, but little else. Reproduction is, so far as is known, similar to that of fanalokas.

If we know little about the eastern falanouc, we know even less about the western falanouc (Eupleres major). It is larger and more darkly furred than its eastern cousin, and lives in a few scattered forests in the northwest of the island, preferring, but not being restricted to, those with regular access to fresh surface water. Given that they were thought to be the same species until 2010, it is likely that it is very similar to its close relative, in support of which, it is thought to mainly eat earthworms and slugs.

One thing we can say is that the western falanouc is rare. That's partly because of it being restricted to a few relatively small forests, but also due to competition from feral cats and dogs, logging of the few forests that remain, and hunting for bushmeat. Thus, while we have no idea how many of the animals remain, the species is officially listed as endangered and a lack of local funding for conservation means that that is unlikely to change any time soon.

There is, however, one further member of the Madagascan carnivores that resembles neither a mongoose nor a civet, and whose placement was long considered puzzling until it was discovered to be a close relative of the fanaloka. Perhaps the best-known mammalian predator on the island, it confusingly happens to have a common name identical to the scientific name of the fanaloka's genus. Next time, I will take a look at that, concluding this particular series.

[Photo by Charles J. Sharp, from Wikimedia Commons, and drawing by Joseph Smit, in the public domain.]