thumb|Cape golden mole ([[Chrysochloris asiatica) adult, showing the digging claw, absence of external eye and a hint of the iridescence of the fur. The rhinarium is not obvious in this photograph.]]
Golden moles are small insectivorous burrowing mammals endemic to Sub-Saharan Africa. They belong to the family Chrysochloridae (the only family in the suborder Chrysochloridea) and as such they are taxonomically distinct from the true moles, family Talpidae, and other mole-like families, all of which, to various degrees, they resemble as a result of evolutionary convergence. There are 21 species. Some (e.g., Chrysochloris asiatica, Amblysomus hottentotus) are relatively common, whereas others (e.g., species of Chrysospalax, Cryptochloris, Neamblysomus) are rare and endangered.
Taxonomy
Despite their extreme evolutionary convergence with moles, their closest relatives are the otter shrews and tenrecs. They are more distantly related to other insectivorous African mammals such as aardvarks and elephant shrews, and even more distantly related to elephants and sirenians.
Characteristics and affinities
Like most burrowing mammals with similar habits, the Chrysochloridae have short legs with powerful digging claws, very dense fur that repels dirt and moisture, and toughened skin, particularly on the head. The fur varies from black to pale yellow or grey, and has an iridescent sheen of green, blue, violet or copper when viewed in light.
Their eyes are non-functional and covered with furred skin. The external ears are just tiny openings. In particular, golden moles bear a remarkable resemblance to the marsupial moles of Australia, family Notoryctidae, which they resemble so suggestively that at one time, the marsupial/placental divide notwithstanding, some argued that they were related. Considerations that influenced the debate might have included the view that the Chrysochloridae are very primitive placentals and the fact that they have many mole-like specializations similar to specializations in marsupial moles.
The rhinarium is a greatly enlarged, dry leathery pad that protects their nostrils while the animal digs. In this respect, too, they resemble the marsupial moles. Some authors claim their primary sense is of touch, and they are particularly sensitive to vibrations, which may indicate approaching danger. Note below, however, the observations on the malleus in the middle ear.
The species range in size from about to about . They have muscular shoulders and the forelimbs are radically adapted for digging; all the toes on the forefeet have been reduced, except for a large, pick-like third claw on the third toe. In comparison to true moles, the fifth digit is absent and the first and fourth digits are vestigial. The adaptations of the hind feet are less dramatic: They retain all five toes and are webbed as an adaptation to efficient backward shoveling of soil loosened by the front claws. and Namibia. They live in a variety of environments; forest, swamps, deserts, or mountainous terrain. Chrysospalax species tend to forage above ground in leaf litter in forests or in meadows. Eremitalpa species such as Grant's golden mole live in the sandy Namib desert, where they cannot form tunnels because the sand collapses. Instead during the day, when they must seek shelter, they "swim" through the loose sand, using their broad claws to paddle, and dive down some to where it is bearably cool. There they enter a state of torpor, thus conserving energy. At night they emerge to forage on the surface rather than wasting energy shifting sand. Their main prey are termites that live under isolated grass clumps, and they might travel for a night in search of food. They seek promising clumps by listening for wind-rustled grass-root stresses and termites' head-banging alarm signals, neither of which can be heard easily above ground, so they stop periodically and dip their heads under the sand to listen.
Morphology
Golden moles share a number of features, varying by species, seldom seen elsewhere among living mammals, including three forearm long-bones, hyoid-mandible articulation, and a hypertrophied malleus. This morphology may be adapted for the detection of seismic signals. In this respect there is some apparent convergent evolution to burrowing reptiles in the family Amphisbaenidae.
Reproduction
Females give birth to one to three hairless young in a grass-lined nest within the burrow system. Breeding occurs throughout the year. The adults are solitary, and their burrowing territory may be aggressively defended from intruders, especially where resources are relatively scarce.