A Field Guide to the Mammals of Egypt. Richard Hoath

Читать онлайн.
Название A Field Guide to the Mammals of Egypt
Автор произведения Richard Hoath
Жанр Биология
Серия
Издательство Биология
Год выпуска 0
isbn 9781617972720



Скачать книгу

for the most part, those from Osborn and Helmy (1980) and in manycases confirmed to museum specimens. These relate to specimens from Egypt as opposed to specimens from outside the country, which may or may not be locally accurate. The measurements for the bats are generally those published by Qumsiyeh (1985). Where there are no Egyptian specimens readily available, as in the Marbled Polecat Vormela peregusna for instance, the measurements are taken from the closest reliable source, e.g., Harrison and Bates (1991). Key measurements are as follows.

      Total length: Length taken from the tip of the nose to the tip of the tail, excluding any terminal tuft.

      Tail length: Length taken from the tip of the tail, excluding any terminal tuft, to the base of the tail.

      Head and body length: Length from the base of the tail to the tip of the nose, which may be obtained by subtracting the tail length from the total length.

      Ear length: Length of the ear from the tip, excluding any tuft, to the base.

      Forearm length: For the bats, the forearm length is given being the distance from the elbow to the wrist, i.e., the ulna.

      Hind foot length: Length of the hind foot from the back of the heel to the tip of the toe, excluding the claws.

      Shoulder height: The height at the shoulder used in the larger mammals, e.g., the ungulates.

      All the above measurements are in millimeters for the smaller species, centimeters for the larger species such as the ungulates, or, in the case of the cetaceans, in meters. While this may seem ungainly, this reflects the accuracy with which mammals of various types are generally recorded. To describe Savi’s Pygmy Shrew as .07m total length or the Fin Whale as 22,000mm long would be to overgeneralize the former and be overly specific about the latter and to misrepresent them both.

      Weight: The weight of a mammal is given, where known, in grams for the smaller species and kilograms for the larger species and tons for the larger cetaceans. See the above note on measurements.

      The insectivores is a heterogeneous order of mammals that includes the familiar hedgehogs, shrews, and moles along with the much less familiar golden moles, solenodons, otter shrews, and tenrecs. In the past, elephant shrews, tree shrews, and flying lemurs, or colugos, have also been lumped into the order, though each is now generally assigned to the orders Macroscelidea, Scandentia, and Dermoptera, respectively. Being such a catch-all group, it is difficult to assign general characteristics to the insectivores. However, they are all small, none heavier than 1,500g and generally much smaller and, indeed, include Savi’s Pygmy Shrew Suncus etruscus, the smallest terrestrial mammal in the world, tipping the scales at a mere 1.5–2.0g. The snout is generally slender, elongated, and highly mobile, the eyes are small or even absent externally, and the fur is short and dense. Many are nocturnal though some, such as the shrews, are active day and night. While the larger insectivores take small vertebrate prey, and some include fruit in their diet, they feed predominantly (as their name suggests) on insects and other invertebrates. Scent is the primary sense used in locating prey.

      Everything points to the insectivores being a very ancient group. They have relatively small brains with few convolutions, the testes do not descend into a scrotal sac, the teeth are primitive and well differentiated, and they possess a cloaca, a common exit for the urino-genital and fecal systems. Being an old group though, some members have developed very specialized adaptations: the moles and golden moles have adapted to life underground, the hedgehog and some tenrecs have developed spines, and some shrews, poisonous saliva.

      Egypt has relatively few insectivore species, two hedgehogs (though this is questioned on taxonomic grounds) and six shrews, though again, their taxonomy is still a matter of debate. Two of these species, the House Shrew Suncus murinus and the Savi’s Pygmy Shrew, are known only from single records and certainly the former is introduced. The paucity of insectivores in Egypt is probably due to the lack of suitable habitat. Many insectivores prefer moist habitats where food and water are plentiful (shrews may eat more than their own body weight daily). Relatively few species are found in the desert, hedgehogs being the main exception, though even they are absent from true desert. The Sahara seems to have provided a very effective barrier to the insectivores as only one species, the Ethiopian Hedgehog Paraechinus aethiopicus, has been recorded in the south of the country. Of the six shrews, the three Crocidura shrews are African species and a fourth, Flower’s Shrew Crocidura floweri, is endemic, while the others have wide ranges over Eurasia. It is probable that these four current Crocidura shrews became isolated in northern Egypt during the climatic warming around six thousand years ago.

      The Hedgehogs and Moonrats—Family Erinaceidae

      17 species worldwide with 2 in Egypt.

      Of the family Erinaceidae, only the hedgehogs, subfamily Erinaceinae, are represented in Egypt, the moonrats being confined to Southeast Asia north to China. The hedgehogs are amongst the most familiar and distinctive insectivores characterized by their relatively large eyes and ears, short, stocky build, and by their entire upper parts being covered in a coat of short spines. Some, but not all, hedgehogs can roll up into a near impregnable ball of spines, the vulnerable underparts and facial region being completely protected.

      There is little agreement about the taxonomy of the hedgehogs, even within Egypt. Here, two species are recognized. The Long-eared Hedgehog Hemiechinus auritus is quite distinctive and placed in the genus Hemiechinus based on cranial characteristics, ear size, and the absence of a spineless ‘parting’ on the crown. It is probably the most likely of all of Egypt’s insectivores to be encountered and certainly the most widespread. The second species, the Ethiopian Hedgehog, is assigned to the genus Paraechinus. Some authors, notably Osborn and Helmy (1980), divide the Ethiopian Hedgehog into three species, the Desert, South Sinai, and Ethiopian Hedgehog. The three are differentiated primarily by spine coloration and facial pattern and are considered by most current authors as one species, the Ethiopian Hedgehog Paraechinus aethiopicus, with three geographically distinct populations in Egypt: the Mediterranean coastal desert, the mountains of South Sinai, and the southern Eastern Desert, respectively. Because of the degree of variation within hedgehog species (some authors split the European Hedgehog Erinaecus europaeus into as many as twelve different species,) it is probable that these three are indeed three isolated populations of the same species, which is how they are treated here.

       Pl. 1

      Long-eared Hedgehog (Hemiechinus auritus)

      Subspecies occurring in Egypt: H. a. aegyptius and H. a. libycus.

      Arabic: Qunfid tawil al-udhun

      Identification: Length 151–245mm; Tail 15–39mm: Weight 400–500g. A small, rather pale hedgehog with distinctively large ears. Upper parts covered in rather short spines, reaching some 1.5cm in length along the back, that are brownish at the base with a broad, cream subtcrminal band and white tip. H. a. libycus averages paler than H. a. aegyptius, with a slightly shorter tail. The underparts are white, often tinged yellow, and the legs and feet, white to whitish. Rather long-legged, especially apparent when trotting. Facial region without spines, with pale brown fur. Snout long and pointed. Ears large, rounded, whitish, and translucent. Unlike other hedgehogs, they emerge well clear of the spines. Tail short. Wide range of vocalizations including snuffling, growling when threatened, and a cat-like hissing.

      Range and status: Wide range from Libya and Egypt across