Long-tailed planigale | |
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Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Infraclass: | Marsupialia |
Order: | Dasyuromorphia |
Family: | Dasyuridae |
Genus: | Planigale |
Species: | P. ingrami |
Binomial name | |
Planigale ingrami (Thomas, 1906) |
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Long-tailed planigale range |
The long-tailed planigale (Planigale ingrami), also known as Ingram's planigale or the northern planigale, is the smallest of all marsupials, and one of the smallest of all mammals. It is rarely seen but is a quite common inhabitant of the blacksoil plains, clay-soiled woodlands, and seasonally flooded grasslands of Australia's Top End.
The long-tailed planigale was described in 1906 by Oldfield Thomas, who placed it in the genus Phascogale. The species was moved in 1928 by Ellis Le Geyt Troughton, who created the genus Planigale for it and the other then-known species, the common planigale (P. maculata), and described the narrow-nosed planigale (P. tenuirostris). The species has since suffered some taxonomic confusion, having been referred to as Planigale subtilissima; there has also been some confusion concerning subspecies. Currently, three subspecies are recognised:
The long-tailed planigale has an extraordinary head shape. All planigales have a flattened head, much broader than it is deep. This smallest planigale takes that trend to an extreme: at just 3 to 4 mm (0.12 to 0.16 in) from top to bottom, the skull is one-fifth as deep as it is wide. The purpose, it seems, is to allow it to squeeze into the tiniest of soil cracks; to find its prey, perhaps to avoid predators, or more probably for both reasons. The clays and blacksoils of the Top End typically develop deep cracks as they dry after the monsoonal summer rains, which persist right through the eight-month dry season until the wet begins again, usually producing floods that force small creatures like the Long-tailed Planigale to seek refuge on high ground.
The head shape aside (which in any case is not obvious from all angles), the long-tailed planigale looks rather like a very small mouse with a long, bare tail. The muzzle is pointed, the fur a nondescript and variable brown, the hindlegs a little bigger than the forelegs, allowing it to stand semi-crouched on hindlegs and tail, rather like a tiny squirrel.