![Chrysochloris asiatica Cape golden mole adult IMG 7120](https://upload.wikimedia.org/wikipedia/commons/b/b8/Chrysochloris_asiatica_Cape_golden_mole_adult_IMG_7120.jpg)
Golden moles are small insectivorous burrowing
mammal
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
s
endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...
to
Sub-Saharan Africa
Sub-Saharan Africa is, geographically, the area and regions of the continent of Africa that lies south of the Sahara. These include West Africa, East Africa, Central Africa, and Southern Africa. Geopolitically, in addition to the List of sov ...
. They comprise the family Chrysochloridae and as such they are
taxonomically
In biology, taxonomy () is the scientific study of naming, defining ( circumscribing) and classifying groups of biological organisms based on shared characteristics. Organisms are grouped into taxa (singular: taxon) and these groups are given ...
distinct from the
true moles, family
Talpidae
The family Talpidae () includes the moles (some of whom are called shrew moles and desmans) who are small insectivorous mammals of the order Eulipotyphla. Talpids are all digging animals to various degrees: moles are completely subterranean a ...
, and other
mole
Mole (or Molé) may refer to:
Animals
* Mole (animal) or "true mole", mammals in the family Talpidae, found in Eurasia and North America
* Golden moles, southern African mammals in the family Chrysochloridae, similar to but unrelated to Talpida ...
-like families, all of which, to various degrees, they resemble as a result of
evolutionary convergence
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last com ...
. 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.
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. 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 mole
Marsupial moles, the Notoryctidae , are highly specialized marsupial mammals, known from two species found at the Australian interior.
* ''Notoryctes typhlops'' (southern marsupial mole, known as the ''itjaritjari'' by the Pitjantjatjara and Yan ...
s of
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
, family
Notoryctidae
Notoryctidae is a family of mammals, allying several extant and fossil species of Australia.
The group appear to have diverged from other marsupials at an early stage and are highly specialised to foraging through loose sand; the unusual feature ...
, which they resemble so suggestively that at one time, the
marsupial
Marsupials are any members of the mammalian infraclass Marsupialia. All extant marsupials are endemic to Australasia, Wallacea and the Americas. A distinctive characteristic common to most of these species is that the young are carried in a po ...
/
placental
Placental mammals (infraclass Placentalia ) are one of the three extant subdivisions of the class Mammalia, the other two being Monotremata and Marsupial
Marsupials are any members of the mammalian infraclass Marsupialia. All extant marsup ...
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
The rhinarium (New Latin, "belonging to the nose"; plural: rhinaria) is the furless skin surface surrounding the external openings of the nostrils in many mammals. Commonly it is referred to as the tip of the ''snout'', and breeders of cats and d ...
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
In physiology, the somatosensory system is the network of neural structures in the brain and body that produce the perception of touch (haptic perception), as well as temperature (thermoception), body position (proprioception), and pain. It is ...
, and they are particularly sensitive to vibrations, which may indicate approaching danger.
Note below, however, the observations on the
malleus
The malleus, or hammer, is a hammer-shaped small bone or ossicle of the middle ear. It connects with the incus, and is attached to the inner surface of the eardrum. The word is Latin for 'hammer' or 'mallet'. It transmits the sound vibrations fro ...
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. 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 shovelling of soil loosened by the front claws.
At one time, the Chrysochloridae were regarded as
primitive. Supporting arguments of this included that they were thought to have originated in
Gondwana
Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final stages ...
, that they had a low resting metabolic rate, and that they could switch off thermoregulation when inactive. Like the
tenrec
A tenrec is any species of mammal within the afrotherian family Tenrecidae endemic to Madagascar. Tenrecs are wildly diverse; as a result of convergent evolution some resemble hedgehogs, shrews, opossums, rats, and mice. They occupy aquatic, a ...
s, they possess a
cloaca
In animal anatomy, a cloaca ( ), plural cloacae ( or ), is the posterior orifice that serves as the only opening for the digestive, reproductive, and urinary tracts (if present) of many vertebrate animals. All amphibians, reptiles and birds, a ...
, and males lack a
scrotum
The scrotum or scrotal sac is an anatomical male reproductive structure located at the base of the penis that consists of a suspended dual-chambered sac of skin and smooth muscle. It is present in most terrestrial male mammals. The scrotum cont ...
. However, these points are no longer regarded as strongly suggestive of golden moles as undeveloped "reptilian mammals"; some are seen rather as adaptations to regional climatic conditions. Going into a torpor when resting or during cold weather enables them to conserve energy and reduce urgent requirements for food. Similarly, they have developed particularly efficient kidneys, and most species do not need to drink water at all; in fact, they tend to drown easily if they fall into water.
Habits and ecology
Chrysochloridae are subterranean, afrotherian mammals endemic to sub-Saharan Africa, and most of which are recorded from South Africa in particular. Other regions include
Lake Victoria, Western Cape,
and Namibia. They live in a variety of environments; forest, swamps, deserts, or mountainous terrain. However, ''
Chrysospalax
''Chrysospalax'' is a small genus of mammal in the family Chrysochloridae. The two members are endemic to South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to th ...
'' species tend to forage above ground in leaf litter in forests or in meadows. ''
Eremitalpa
Grant's golden mole (''Eremitalpa granti''; colloquially also: ''dune shark'') is a golden mole species. It is the only member of the genus ''Eremitalpa''.
Attributes
Like all other golden moles, the build of these animals is similar to the mo ...
'' species such as Grant's golden mole live in the sandy
Namib desert
The Namib ( ; pt, Namibe) is a coastal desert in Southern Africa. The name is of Khoekhoegowab origin and means "vast place". According to the broadest definition, the Namib stretches for more than along the Atlantic coasts of Angola, Namib ...
, 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 50 cm to where it is bearably cool. There they enter a state of torpor, thus conserving energy.
[ Piper, Ross (2007), ''Extraordinary Animals: An Encyclopedia of Curious and Unusual Animals'', ]Greenwood Press
Greenwood Publishing Group, Inc. (GPG), also known as ABC-Clio/Greenwood (stylized ABC-CLIO/Greenwood), is an educational and academic publisher (middle school through university level) which is today part of ABC-Clio. Established in 1967 as Gr ...
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 6 kilometres 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.
Most other species construct both foraging superficial burrows and deeper permanent
burrow
An Eastern chipmunk at the entrance of its burrow
A burrow is a hole or tunnel excavated into the ground by an animal to construct a space suitable for habitation or temporary refuge, or as a byproduct of locomotion. Burrows provide a form of sh ...
s for residence. Residential burrows are relatively complex in form, and may penetrate as far as a metre below ground and include deep chambers for use for refuge, and other chambers as latrines. They push excavated soil up to the surface, as in mole-hills, or compact it into the tunnel walls.
They feed on small insects and earthworms or small vertebrates such as lizards or burrowing snakes. They depend on their sense of hearing to locate much of their prey, and the
cochlea
The cochlea is the part of the inner ear involved in hearing. It is a spiral-shaped cavity in the bony labyrinth, in humans making 2.75 turns around its axis, the modiolus. A core component of the cochlea is the Organ of Corti, the sensory org ...
s of a number of golden mole species have been found to be long and highly coiled, which may indicate a greater ecological dependence on low frequency auditory cues than we see in
Talpid moles.
Morphology
Golden Moles share a number of features, varying by species, seldom seen elsewhere among living mammals, including three forearm long-bones,
hyoid
The hyoid bone (lingual bone or tongue-bone) () is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. At rest, it lies between the base of the mandible and the third cervical vertebra. ...
-
mandible
In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower tooth, teeth in place. The mandible sits beneath the maxilla. It is the only movabl ...
articulation, and a hypertrophied
malleus
The malleus, or hammer, is a hammer-shaped small bone or ossicle of the middle ear. It connects with the incus, and is attached to the inner surface of the eardrum. The word is Latin for 'hammer' or 'mallet'. It transmits the sound vibrations fro ...
.
Some species have hypertrophied (enlarged) middle ear
ossicles
The ossicles (also called auditory ossicles) are three bones in either middle ear that are among the smallest bones in the human body. They serve to transmit sounds from the air to the fluid-filled labyrinth (cochlea). The absence of the auditory ...
, in particular the malleus. These animals have the largest malleus relative to body size of any animal. 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
The Amphisbaenidae (common name: worm lizards) are a family of amphisbaenians, a group of limbless vertebrates.
Geographic range
Amphisbaenids occur in South America, some Caribbean islands, Europe, and sub-Saharan Africa.
Taxonomy
One deep- ...
.
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.
[
]
Status
Of the 21 species of golden mole, no fewer than 11 are threatened with extinction. The primary cause being human-induced habitat loss, additionally sand mining
Sand mining is the extraction of sand, mainly through an open pit (or sand pit) but sometimes mined from beaches and inland dunes or dredged from ocean and river beds. Sand is often used in manufacturing, for example as an abrasive or in concret ...
, poor agricultural practices, and predation by domestic cats and dogs are causes of population decline.
Classification
The taxonomy of the Chrysochloridae is undergoing a review in the light of new genetic information. They have traditionally been listed with the shrew
Shrews (family Soricidae) are small mole-like mammals classified in the order Eulipotyphla. True shrews are not to be confused with treeshrews, otter shrews, elephant shrews, West Indies shrews, or marsupial shrews, which belong to different fa ...
s, hedgehog
A hedgehog is a spiny mammal of the subfamily Erinaceinae, in the eulipotyphlan family Erinaceidae. There are seventeen species of hedgehog in five genera found throughout parts of Europe, Asia, and Africa, and in New Zealand by introducti ...
s and a grab-bag of small, difficult-to-place creatures as part of the order Insectivora
The order Insectivora (from Latin ''insectum'' "insect" and ''vorare'' "to eat") is a now-abandoned biological grouping within the class of mammals. Some species have now been moved out, leaving the remaining ones in the order Eulipotyphla, w ...
. Some authorities retain this classification, at least for the time being. Others group the golden moles with the tenrec
A tenrec is any species of mammal within the afrotherian family Tenrecidae endemic to Madagascar. Tenrecs are wildly diverse; as a result of convergent evolution some resemble hedgehogs, shrews, opossums, rats, and mice. They occupy aquatic, a ...
s in a new order, which is sometimes known as Tenrecomorpha
Tenrecomorpha is the suborder of otter shrews and tenrecs, a group of afrotherian mammals indigenous to equatorial Africa and Madagascar, respectively. The two families are thought to have split about 47–53 million years ago. Potamogalid ot ...
, while others call it Afrosoricida
The order Afrosoricida (a Latin-Greek compound name which means "looking like African shrews") contains the golden moles of Southern Africa, the otter shrews of equatorial Africa and the tenrecs of Madagascar. These three families of small mamma ...
and reserve Tenrecomorpha for the family Tenrecidae.
* ORDER AFROSORICIDA
The order Afrosoricida (a Latin-Greek compound name which means "looking like African shrews") contains the golden moles of Southern Africa, the otter shrews of equatorial Africa and the tenrecs of Madagascar. These three families of small mamma ...
** Suborder Tenrecomorpha
Tenrecomorpha is the suborder of otter shrews and tenrecs, a group of afrotherian mammals indigenous to equatorial Africa and Madagascar, respectively. The two families are thought to have split about 47–53 million years ago. Potamogalid ot ...
*** Family Tenrecidae: tenrecs, 34 species in 10 genera
** Suborder Chrysochloridea
*** Family Chrysochloridae
**** Subfamily Chrysochlorinae
***** Genus ''Carpitalpa
Arends'
golden mole (''Carpitalpa arendsi'') is a species of mammal in the family Chrysochloridae. It is found in Mozambique and Zimbabwe. Its natural habitats are temperate forests, subtropical or tropical dry, and moist montane forests, dry ...
''
****** Arends's golden mole
Arends'
golden mole (''Carpitalpa arendsi'') is a species of mammal in the family Chrysochloridae. It is found in Mozambique and Zimbabwe. Its natural habitats are temperate forests, subtropical or tropical dry, and moist montane forests, dry ...
(''Carpitalpa arendsi'')
***** Genus ''Chlorotalpa
''Chlorotalpa'' is a genus of mammal in the family Chrysochloridae. It contains the following species:
* Duthie's golden mole (''Chlorotalpa duthieae'')
* Sclater's golden mole
Sclater's golden mole (''Chlorotalpa sclateri'') is a species of ...
''
****** Duthie's golden mole (''Chlorotalpa duthieae'')
****** Sclater's golden mole
Sclater's golden mole (''Chlorotalpa sclateri'') is a species of mammal in the family Chrysochloridae. It is found in Lesotho and South Africa. Its natural habitats are subtropical or tropical dry and high-altitude shrubland, Mediterranean-type s ...
(''Chlorotalpa sclateri'')
***** Genus ''Chrysochloris
''Chrysochloris'' is a genus of mammal in the family Chrysochloridae.
It contains the following species:
* Subgenus ''Chrysochloris''
**Cape golden mole
The Cape golden mole (''Chrysochloris asiatica'') is a small, insectivorous mammal of ...
''
****** Subgenus ''Chrysochloris''
******* Cape golden mole
The Cape golden mole (''Chrysochloris asiatica'') is a small, insectivorous mammal of the family Chrysochloridae, the golden mole
Golden moles are small insectivorous burrowing mammals endemic to Sub-Saharan Africa. They comprise the family ...
(''Chrysochloris asiatica'')
******* Visagie's golden mole (''Chrysochloris visagiei'')
****** Subgenus ''Kilimatalpa''
******* Stuhlmann's golden mole (''Chrysochloris stuhlmanni'')
***** Genus ''Chrysospalax
''Chrysospalax'' is a small genus of mammal in the family Chrysochloridae. The two members are endemic to South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to th ...
''
****** Giant golden mole (''Chrysospalax trevelyani'')
****** Rough-haired golden mole (''Chrysospalax villosus'')
***** Genus ''Cryptochloris
''Cryptochloris'' is a genus of golden mole
Golden moles are small insectivorous burrowing mammals endemic to Sub-Saharan Africa. They comprise the family Chrysochloridae and as such they are taxonomically distinct from the true moles, fami ...
''
****** De Winton's golden mole
De Winton's golden mole (''Cryptochloris wintoni'') is a species of mammal in the family Chrysochloridae. It is endemic to South Africa. Its natural habitats are subtropical dry shrubland, Mediterranean-type shrubby vegetation, and sandy shores. I ...
(''Cryptochloris wintoni'')
****** Van Zyl's golden mole
Van Zyl's golden mole (''Cryptochloris zyli'') is a golden mole endemic to the Western Cape Province, South Africa. It is listed as an endangered species due to habitat loss. Golden moles are an ancient group of mammals who live mostly below grou ...
(''Cryptochloris zyli'')
***** Genus ''Eremitalpa
Grant's golden mole (''Eremitalpa granti''; colloquially also: ''dune shark'') is a golden mole species. It is the only member of the genus ''Eremitalpa''.
Attributes
Like all other golden moles, the build of these animals is similar to the mo ...
''
****** Grant's golden mole
Grant's golden mole (''Eremitalpa granti''; colloquially also: ''dune shark'') is a golden mole species. It is the only member of the genus ''Eremitalpa''.
Attributes
Like all other golden moles, the build of these animals is similar to the m ...
(''Eremitalpa granti'')
**** Subfamily Amblysominae
Golden moles are small insectivorous burrowing mammals endemic to Sub-Saharan Africa. They comprise the family Chrysochloridae and as such they are taxonomically distinct from the true moles, family Talpidae, and other mole-like families, all ...
***** Genus ''Amblysomus
''Amblysomus'' (also narrow-headed golden mole or South African golden mole) is a genus of the golden mole family, Chrysochloridae, comprising five species of the small, insect-eating, burrowing mammals endemic to Southern Africa. All five spec ...
''
****** Fynbos golden mole
The fynbos golden mole (''Amblysomus corriae'') is a species of mammal in the golden mole family, Chrysochloridae. It is endemic to South Africa.
Its natural habitats are fynbos vegetation, temperate forests, shrubland, and grassland, subtropi ...
(''Amblysomus corriae'')
****** Hottentot golden mole
The Hottentot golden mole (''Amblysomus hottentotus'') is a species of mammal in the golden mole family, Chrysochloridae. It is found in South Africa, Eswatini, and possibly Lesotho. Its natural habitats are temperate forests, subtropical or ...
(''Amblysomus hottentotus'')
****** Marley's golden mole
Marley's golden mole (''Amblysomus marleyi'') is a species of burrowing mammal in the golden mole family, Chrysochloridae. It is found in South Africa and possibly Eswatini. It has been separated from ''Amblysomus hottentotus'' by Bronner (1995 ...
(''Amblysomus marleyi'')
****** Robust golden mole
The robust golden mole (''Amblysomus robustus'') is a species of mammal in the golden mole family, Chrysochloridae. It is endemic to parts of Mpumalanga province in South Africa. Its natural habitats are temperate forests, subtropical or tropi ...
(''Amblysomus robustus'')
****** Highveld golden mole
The highveld golden mole (''Amblysomus septentrionalis'') is a species of mammal in the golden mole family, Chrysochloridae. It is found in South Africa and Eswatini. Its natural habitats are forests, moist savanna, temperate shrubland and gras ...
(''Amblysomus septentrionalis'')
***** Genus ''Calcochloris
''Calcochloris'' is a genus of mammal in the family Chrysochloridae.
It contains the following species:
* Yellow golden mole (''Calcochloris obtusirostris'')
* Somali golden mole
The Somali golden mole (''Calcochloris tytonis'') is a golden ...
''
****** Subgenus ''Calcochloris''
******* Yellow golden mole
The yellow golden mole (''Calcochloris obtusirostris'') is a species of mammal in the family Chrysochloridae. It is found in Mozambique , South Africa (KwaZulu-natal and the Limpopo), and Zimbabwe. The yellow golden mole's natural habitats are su ...
(''Calcochloris obtusirostris'')
****** Subgenus ''incertae sedis
' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty ...
''
******* Somali golden mole
The Somali golden mole (''Calcochloris tytonis'') is a golden mole endemic to Somalia. In 1964, Dr. Alberto Simonetta of the University of Florence discovered the mole's jaw and ear bone fragments in a barn owl pellet in Giohar, Somalia. The Soma ...
(''Calcochloris tytonis'')
*****Genus ''Huetia''
****** Congo golden mole (''Huetia leucorhina'')
***** Genus '' Neamblysomus''
****** Juliana's golden mole
Juliana's golden mole (''Neamblysomus julianae'') is a golden mole endemic to South Africa. It is listed as an endangered species due to habitat loss and a restricted range. Golden moles are an ancient group of mammals that live mostly below gro ...
(''Neamblysomus julianae'')
****** Gunning's golden mole
Gunning's golden mole (''Neamblysomus gunningi'') is a small mammal endemic to South Africa. It was listed in 2006 as an endangered species. Its decreasing numbers are due to habitat clearance or destruction and predation from domesticated cats a ...
(''Neamblysomus gunningi'')
References
{{DEFAULTSORT:Golden Mole
Afrosoricida
Extant Lutetian first appearances
Taxa named by John Edward Gray