Saturday, April 5, 2008

Cuban solenodon (Solenodon cubanus)


This primitive insectivore resembles a large stoutly-built shrew. Like its relative the Hispaniolan solenodon (S. paradoxus), this species is thought to secrete toxic saliva to subdue its prey. The solenodons diverged from all other mammal groups an incredible 76 million years ago and were, until recently, among the dominant predators of the West Indies. The species was almost wiped out by introduced predators such as dogs, cats and mongooses following European colonisation of Cuba, and was believed to be extinct until a single individual was captured in 2003.
Evolutionary Distinctiveness
Order: Insectivora
Family: Solenodontidae

Recent genetic studies have revealed that the solenodons diverged from all other living mammals during the Cretaceous Period, an incredible 76 million years ago. This separation occurred at least as long ago as the branching of many entire mammalian orders (e.g. pangolins versus carnivores, or manatees versus elephants).Fossil evidence shows that solenodon-like insectivores existed in North America 30 million years ago. They are thought to have originated from North American insectivores that colonised the Greater Antilles by overwater dispersal from Central America or the southeastern United States.There are only two species of solenodon alive today, the Cuban solendon (S. cubanus) and the Hispaniolan solenodon (S. paradoxus). Two additional species, S. arredondoi and S. marcanoi, are known only from skeletal remains collected from western Cuba and southwestern Hispaniola respectively.The two living solenodon species are believed to have diverged around 25 million years ago, when northern Hispaniola separated from eastern Cuba. This separation is comparable to the divergence between distinct mammalian families, for example, dolphins versus whales (30 Myr ago), or humans versus Old World monkeys (23 Myr ago). On this basis some researchers argue that the two species should be placed in different genera, with the Cuban solenodon being placed in a distinct genus, Atopogale.
Description
Size: Head and body length: approx. 280-390 mm
Tail length: approx. 175-255 mm
Weight: 1 kg

With its small eyes and long snout, which is supported by a rod of cartilage, this primitive insectivore resembles a large stoutly-built shrew. It has a thick scaly tail and large ears which are almost hairless. The rest of the body is covered in patchy fur which is blackish brown in colour flecked with white or buff. Solenodons have tiny eyes and their vision is very poor, although their sense of smell and hearing are well developed. The front legs are longer than the hind legs and the five toes on each foot are equipped with powerful claws for digging.
Ecology
The species is nocturnal, spending the day hiding in rock clefts, hollow trees or burrows which they dig themselves. At night they come out to search for food. They use their long snouts to root around for invertebrates, and their claws to uncover or dig them up. Solenodons subdue their prey by injecting them with venom through special grooves in their incisors. They are the only mammals known to do this. Insects and spiders are the main prey species, although some small reptiles, roots, fruit and leaves are also eaten.Solenodons are relatively social animals and live in family groups of up to eight individuals in the same burrow. The species is relatively long-lived, with one individual surviving for more than six years in captivity. However, reproductive rates are low, with females giving birth to just two litters of typically a single young per year.
Habitat
Inhabits dense humid forests and brush country to elevations of 2000 m.
Distribution
Until relatively recently the species was widely distributed in both the eastern and western ends of Cuba, although it appears to have been largely absent from the centre of the island. Today it is limited to Oriente Province at the eastern end of Cuba.
Population Estimate
No current estimates, but probably very rare. The species has been considered extinct at various times during the past century. Individuals have been captured in 1974 and 1975, and as recently as 2003.
Status
Classified as Endangered (EN A1cde) on the 2006 IUCN Red List of Threatened Species.
Threats
Like many other Antillean animals, this species declined following European colonisation of the West Indies. Most of its preferred forest habitat has now been lost to agriculture and development, and only an estimated 15% of the island's original vegetation cover remains. The species is also an easy target for introduced predators, such as dogs, cats and mongooses. Since the species had no natural predators before European colonisation of Cuba, and is a slow clumsy mover, it does not possess many defences against introduced animals.
Conservation Underway
The species is protected by the USDI (United States Department of the Interior) and important populations occur within at least two National Parks (the Alejandro de Humboldt National Park in the north-eastern part of Cuba, and the Sierra del Cristal National Park, in Holguin province in eastern Cuba). A survey was conducted in the Sierra del Cristal National Park in 2002 by a multidisciplinary team from the Empresa Nacional para la Proteccion de la Flora y Fauna (ENPFF, Cuba) and the Instituto de Ecologia y Sistematica (IES, Cuba), in collaboration with the Durrell Wildlife Conservation Trust (Jersey, UK). The results of this survey will form the basis for developing a long-term management plan for the species in this area.

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