''Chersobius signatus'' is the world's smallest

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

tortoise Tortoises () are reptiles of the family Testudinidae of the order Testudines (Latin: ''tortoise''). Like other turtles, tortoises have a turtle shell, shell to protect from predation and other threats. The shell in tortoises is generally hard, ...

(

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Testudinidae). The species is commonly known as the speckled tortoise and also known locally as the speckled padloper and internationally as the speckled Cape tortoise. A member of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

Chersobius ''Chersobius'' is a genus of tiny tortoises in the family Testudinidae, endemic to southern Africa. The genus includes the smallest tortoises in the world. All three species were previously assigned to the genus ''Homopus''. Naming As a group, ...

'', it is

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 ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...

.Homopus Research Foundation
web site (accessed August 24, 2013).

Distribution and subspecies

''C. signatus'' is naturally restricted to a small area in

Little Namaqualand Namaqualand (khoekhoe: "Nama-kwa" meaning Nama Khoe people's land) is an arid region of Namibia and South Africa, extending along the west coast over and covering a total area of . It is divided by the lower course of the Orange River into ...

, an arid region in the west of South Africa, where it normally lives on rocky outcrops and forages among the rocks for the tiny succulent plants it eats. In the past, two

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

were recognized, the Namaqualand speckled padloper (''C. s. signatus'') and the southern speckled padloper (''C. s. cafer''), but genetic studies have determined this was not supported and they are now considered a single species.Daniels SR, Hofmeyr MD, Henen BT, Baard EHW (2010). "Systematics and phylogeography of a threatened tortoise, the speckled padloper". ''Animal Conservation'' 13 (3): 237-246.

Description

The males of ''C. signatus'' measure in straight

carapace A carapace is a Dorsum (biology), dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tor ...

length, while the larger females measure up to almost ; they weigh about . This species has a flattened shell with slightly serrated edges. The orange-brown shell is covered in hundreds of black spots. The males have a noticeably concave belly. This tiny tortoise can be distinguished from the other ''Chersobius'' species by its speckles, and by five toes on its fore feet (unlike many of its relatives, which have four toes on all four feet).

Life cycle and behaviour

Speckled padlopers are most active in the early morning (especially in autumn and spring, when they breed). Living among the rocky outcrops, they feed on small succulents that grow between the rocks and are small enough to reach. Their courtship involves the male and female nodding their heads at each other. After mating, the female makes a nest of several eggs in damp soil between the rocks. The hatchlings are under 7 grams and long, and emerge after 100 to 120 days. The average mature female speckled tortoise produces about ≤ 5 eggs per year.

Threats and conservation

''C. signatus'' is threatened by traffic on roads, habitat destruction, and

poaching Poaching has been defined as the illegal hunting or capturing of wild animals, usually associated with land use rights. Poaching was once performed by impoverished peasants for subsistence purposes and to supplement meager diets. It was set a ...

for the pet trade. As the trade in collected ''Chersobius'' species is strictly illegal and any captive specimens are systematically registered in noncommercial studbooks in South Africa and Namibia, any commercial sale of ''Chersobius'' tortoises is almost without exception strictly illegal. Another threat comes from introduced species, such as domestic dogs and pigs. Many are taken from their natural habitat each year, and nearly all subsequently die as a result, as they do not readily adapt to typical captive diets and environmental change. Unlike most other ''Chersobius'' species, however, their diet (while very varied) is not highly specialised. Therefore, the species can adapt well to captivity, provided that proper attention is paid to temperature, humidity, and a sufficiently varied diet. They can be very hardy in captivity, and most problems with captive care are caused by faulty nutrition, high humidity, dampness, or bad husbandry.Corton, Misty
''Homopus'' (Padloper Tortoise) Care
World Chelonian Trust (retrieved August 20, 2013).Loehr, Victor.

, World Chelonian Trust (retrieved August 20, 2013).Palmer, Mike (1994)

, ''Tortuga Gazette'' 30 (6): 1–5. June 1994.

References

{{Taxonbar , from=Q302172 Chersobius Reptiles of South Africa Reptiles described in 1801 Taxa named by Johann Friedrich Gmelin