Richmond's croissant

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Richmond's croissant
Systematics
Subordination : Squirrel relatives (Sciuromorpha)
Family : Squirrel (Sciuridae)
Subfamily : Tree squirrel and flying squirrel (Sciurinae)
Tribe : Tree squirrel (Sciurini)
Genre : Red squirrel ( Sciurus )
Type : Richmond's croissant
Scientific name
Sciurus richmondi
Nelson , 1898

Richmond's squirrel ( Sciurus richmondi ) is a species of squirrel from the genus of squirrels ( Sciurus ). It occurs exclusively in Nicaragua .

features

Richmond's croissant reaches a head-torso length of about 16.0 to 21.8 centimeters, and a tail that is about 13.0 to 18.4 centimeters long. The weight is 235 to 268 grams. The back is evenly colored dark brown with ocher washings, the belly is yellow-sand-colored to yellow-orange. The upper side of the tail corresponds in its coloring to the fur on the back, on the underside it is yellow-brown-ocher colored.

1 · 0 · 1 · 3  =  20
Tooth formula from Richmond's croissant

The skull is long, with a length of 48.3 to 51.5 centimeters, and broad, the cranium is flattened and postorbitally curved. The tympanic bubbles are comparatively small. The type has too a maxillary per half incisor tooth formed incisor (incisor) to which a tooth gap ( diastema follows). This is followed by a premolar and three molars . The teeth in the lower jaw correspond to those in the upper jaw. In total, the animals have a set of 20 teeth.

distribution

Richmond's squirrel is endemic to Nicaragua in southern Central America.

Way of life

Richmond's squirrel lives in lowland regions in gallery forests and primary forest stands up to heights of 1000 meters; it can also occur in plantations and secondary forest stands. Only very limited data and observations are available on the way of life of the animals. Like other species of squirrel, it is diurnal and lives in the trees, the animals are probably solitary animals. They look for food primarily on the ground and in the lower areas of the trees, less often in higher tree layers.

The breeding season extends from February to September, the litter consists of two or three young animals that are born in the nest.

Systematics

Richmond's squirrel is classified as a separate species within the genus of squirrels ( Sciurus ), which consists of almost 30 species. The first scientific description comes from Edward William Nelson from 1898, who described the species on the basis of individuals on the Río Escondido in Nicaragua. The species was named after Charles W. Richmond , who collected the type specimens used to describe it.

Apart from the nominate form, no subspecies are distinguished within the species .

Status, threat and protection

Richmond's croissant is listed by the International Union for Conservation of Nature and Natural Resources (IUCN) as a type of warning list ("near threatened"). This is justified with the limited habitat of less than 20,000 km 2 with only a few populations and the assumption that stocks are declining. On the basis of these assessments, however, a classification as an endangered species (“vulnerable”) is likely possible. The decline in forests and the fragmentation of forest areas in the habitat of the species are considered to be the main causes of risk; hunting only plays a subordinate role.

supporting documents

  1. ↑ a b c d e f g Richard W. Thorington Jr. , John L. Koprowski, Michael A. Steele: Squirrels of the World. Johns Hopkins University Press, Baltimore MD 2012, ISBN 978-1-4214-0469-1 , pp. 67 .
  2. ↑ a b c J. Knox Jones Jr., Hugh H. Genoways: Sciurus richmondi. Mammalian Species 53, 1975. ( full text )
  3. ↑ a b c Sciurus richmondi in the IUCN Red List of Threatened Species 2015.3. Posted by: J. Koprowski, L. Roth, 2008. Retrieved November 14, 2015.
  4. ↑ a b Sciurus richmondi In: Don E. Wilson , DeeAnn M. Reeder (Ed.): Mammal Species of the World. A taxonomic and geographic Reference. 2 volumes. 3. Edition. Johns Hopkins University Press, Baltimore MD 2005, ISBN 0-8018-8221-4 .

literature

Web links