Proboscis

Proboscis
Proboscis rat ( Petrodromus tetradactylus )
Systematics
Superordinate : Afrotheria without rank: Afroinsectiphilia Order : Elephant jerk (Macroscelidea) Family : Elephant jerk (Macroscelididae) Genre : Proboscis Type : Proboscis
Scientific name of the  genus
Petrodromus
Peters , 1846
Scientific name of the  species
Petrodromus tetradactylus
Peters , 1846

The proboscis rat ( Petrodromus tetradactylus ), also four-toed proboscis , is a species of mammal from the family of the elephants (Macroscelididae). It is one of the larger representatives of its family and, like other elephants, is characterized by a large head with a typical, trunk-like elongated nose and long hind and short front legs. A special feature are bristle-like hairs on the underside of the tail, which sometimes have a button-like or knot-like end and whose function is not fully understood. Overall, the proboscis appears to be very varied, which results in numerous subspecies. Their distribution area includes central, eastern and south-eastern Africa. As a result, forests, floodplains and bush landscapes are primarily inhabited. The main food consists of insects , plants are also less commonly eaten. The animals live in monogamous pairs, the offspring of which consists of one or two young per litter. They maintain their own territory with a dense network of paths and paths. These connect the individual areas of activity and shelter. The species was first mentioned scientifically in 1846. The entire population of the proboscis is considered safe.

description

Habitus

Prepared specimens of the proboscis in the Royal Museum for Central Africa in Tervuren, Belgium

The proboscis is a medium-sized representative of the proboscis and the largest of the common kin group with the elephant shrews ( Elephantulus ) and with Macroscelides . It reaches a total length of 31.8 to 38 cm, the head-trunk length is 16.3 to 21 cm, the tail is 14.7 to 18.7 cm long. The tail is around 85% the length of the rest of the body. The weight is 129 to 280 g. In the coastal area of ​​East Africa no pronounced sexual dimorphism could be identified, further inland and to the south, females are on average slightly larger than males. The average weight of the males in the Arabuko Sokoke Forest in eastern Kenya was 198 g, that of the females 208 g. In KwaZulu-Natal in South Africa the mean weight for males was 182 g and for females 204 g. Like other elephants, the proboscis rat is characterized by a large head with a trunk-like elongated nose and comparatively short front legs compared to the hind legs. The fur is extremely soft, the hair on the back is longer than on the stomach. The color of the fur on the back appears varied, from rust to sand to dark brown to gray. With some representatives, an indistinct, broad and dark stripe can be formed along the middle of the back. The sides of the body show a yellowish-brown to orange-gray to light-gray color, sometimes a gray or brown stripe is present. The belly of some females can have a washed-out ocher-gray color, otherwise it is predominantly tinted whitish-gray, as are the legs. The sparsely hard tail is black on top, but lighter on the underside. A hairless patch of skin appears at the base. Noticeable are bristle-like hairs up to 7 mm in length, which cover the rear third of the underside of the tail and sometimes end in a knot-like or button-like thickening.

The large head has a moderately elongated snout. The upper lips, the chin and the throat are colored whitish, in front of the eyes the muzzle has a reddish brown tone. The large eyes are framed by a clear, light eye ring that is enlarged at the ears. A dark spot appears below this enlargement, which partially interrupts the eye ring here. The ears are set far apart, are wide and rust-colored to yellowish-brown in color, and white hairs grow inside. The length of the ears is 34 to 39 mm. The top of the clawed feet is yellowish brown. The forefoot has five toes, the third and fourth rays are longest, the second and fifth are set back by nail length, while the innermost toe only extends to the base of the next outer (second). In contrast to the elephant shrews and macroscelides , only four toes are formed on the rear foot, the size of the rays corresponds to that of the forefoot with the exception that the innermost toe is completely reduced. The length of the rear foot varies from 51 to 58 mm. Also different from Macroscelides and Elephantulus , the proboscis female only has two pairs of teats , one in the breast and one in the abdomen.

Skull and dentition features

The skull reaches a length of 54.3 to 58.5 mm, at the zygomatic arches it is 28.1 to 30.5 mm wide. When viewed from above, it shows a very narrow structure; when viewed from the side, a dome-like bulge of the rear skull is visible. The zygomatic arches are well developed, as is the tympanic bladder , which has prominent parts on the sphenoid bone and on the tympanic part . But it is not as bloated as in Macroscelides . The parietal ridge is limited to the back half of the parietal bones . The tear bone is very large overall. There are three pairs of openings in the palatine bone , the number and size correspond to those of the elephant shrews and the Macroscelides species, but differ from the proboscis dogs ( Rhynchocyon ). However, in contrast to the first two mentioned, there are no larger openings between the first rear molars. The teeth comprises 40 teeth and has the following tooth formula : . The first incisor protrudes over the two outer teeth by twice as long and has a canine-like ( caniniform ) shape. The outer (third) incisor is isolated from the front and is slightly larger than the second. While the canine, which is separated from the incisors by a diastema and is around 4 mm high, corresponds in shape to the third incisiform ( incisiform ), the first premolar again resembles a canine. The third premolar is similar to the molars ( molar-shaped ). The length of the upper row of teeth is 28.1 to 30.5 mm. ${\displaystyle {\frac {3.1.4.2}{3.1.4.2}}}$

distribution

Distribution area (brown) of the proboscis

The proboscis lives in central, eastern and south-eastern Africa . Their distribution area extends from the Democratic Republic of the Congo through Uganda and Kenya as well as most of Tanzania and Zambia to Mozambique , southeastern Zimbabwe , the easternmost part of Angola and northern South Africa . She can also be found on the offshore islands of Zanzibar and possibly Mafia . Reports of sightings from the Caprivi Strip in Namibia have not yet been confirmed. The occurrence in the Congo Basin is spatially separated from the rest of the distribution area of ​​the species. The mainly inhabited landscapes are composed of the Zambezi woodland zone , the coastal forests with open mosaic landscapes and the southern rainforest - savannah landscapes , with an annual rainfall of at least 700 mm. A subspecies also lives in the tropical rainforests of the Congo Basin , but does not appear to be found north of the Congo there. The altitude distribution ranges from sea level to highland areas around 1400 m, in the Taita Mountains in southeastern Kenya possibly up to 2200 m.

The habitats of the proboscis consist of riparian forests and forests with dense undergrowth, partly also from bushland. The species is relatively common in general, but the population density varies with the individual habitats and with the season. In the coastal forests of northeastern Tanzania, almost twice as frequent the presence of the weevil was recorded during the dry season as compared to the rainy season. In the Arabuko Sokoke Forest , a roughly 420 km² coastal forest in Kenya south of the Tana , it occurs predominantly in landscapes with Cynometra vegetation communities, with around half of records it is significantly less common in areas with Afzelia populations, while it is found in Brachystegia landscapes was hardly observed. A population density of around 2.1 individuals per hectare was found in the Afzelia plant stocks. In the coastal forests of Kenya, the proboscis also occurs sympathetically with the golden proboscis dog ( Rhynchocyon chrysopygus ), which lives in a similar habitat. However, the proboscis uses regions with denser underground or bush vegetation. In the Congo Basin, the proboscis rat shares the landscapes with the dark elephant shrew ( Rhynchocyon chair manni ), it is rather associated there with old, original landscapes where mostly marantaceae or Entandrophragma dominate -Gewächse, also is observed more frequently in river basins. In the Tembe Elephant Park of KwaZulu-Natal in the southernmost part of the distribution area of ​​the proboscis, where forests thrive on sandy soils, only a very low population density could generally be determined.

Way of life

Territorial behavior

Depiction of the proboscis from 1852

The trunk rat is polycyclically active, but mostly during the twilight period and during the day. The main activities take place in the morning from 5 a.m. to 10 a.m. and in the evening from 4 p.m. to 8 p.m., sometimes until 10 p.m., during the hottest phase of the day the proboscis is mostly resting. The times of the activities are sometimes interrupted by short periods of rest, which, however, do not last longer than 30 minutes. During this, an animal does not lie on its side and seldom closes its eyes completely, so that it is always alert. The proboscis lives on the ground and can move very quickly ( cursorial ) running and jumping on four feet, with the tail held upright. Their way of life is, however, very hidden, so that it can only be partially detected through traces of activity in one region. For comfort behavior include the "face wash" with his front paws, scratching and extensive sand baths.

The individual individuals maintain action spaces . According to studies in the Arabuko Sokoke Forest in Kenya, these have an area of ​​around 1.4 ha in females and are therefore only slightly larger than those of the males with 1.1 ha. Observations in the Sodwana Bay National Park in eastern KwaZulu-Natal have shown similar values . In the Tembe Elephant Park , also in KwaZulu-Natal, on the other hand, males with 1.2 hectares have almost twice as large areas as females, whose action areas are only 0.7 hectares. In some females, however, significantly larger territories were found here. Depending on the density of the population of a region, the neighboring territories of members of the same sex can partially overlap, but this usually takes up less than a third of the area. Within the action areas there are one or more core zones that are used by the individual animals. These can contain between 2 and 11, on average 5 hiding places, which consist of tree hollows, fallen trunks or dense vegetation, more rarely burrows of other digging animals. The proboscis does not build its own burrows or special nests. The various residence areas in the territory are connected by a dense network of paths. The paths and paths are around 10 cm wide and are laid out by the proboscis with sweeping movements of the front legs. Sometimes they only consist of a string of cleaned spots 10 to 20 cm in diameter, which are about 30 cm apart. Especially in dense underground vegetation they can last for a long time, in more open terrain they are rather unstable and are often replaced by new ones within a period of a few weeks. They are mainly used for rapid movement or for escaping.

As with other elephants, the trunk rat lives in monogamous relationships that usually last for life. With the tied animals, the territories of the individual partners partially or completely overlap. The complete overlap of the territories is likely to depend on the density of the population in the inhabited region and occurs especially when it is particularly high. Joint activities of the partners take place outside of the mating season, however, only rarely. As a rule, each animal retreats to its own shelter, the paths within the territories are used by both partners, but rarely at the same time in the same place. During studies in the Sodwana Bay National Park, a certain polygynous behavior could also be observed, but this is attributed to the fact that the males were subadult in age. Whether the proboscis, like some other elephants, is also territorial cannot yet be clearly proven from observations in the wild. In captive animals, however, this could be demonstrated between members of the sexes.

The intra-species communication often takes place via scent marks. The bristle-like hairs on the underside of the tail may also be used to distribute such secretions , as there are numerous glands there and the animals often brush the ground with sideways movements of the tail (the bristles were sometimes also with the detection of floor vibrations or with the creation of paths as originally thought to be the results of bush fires). Only a few vocalizations are known. They range from a purr and click to a scream in the event of interference. Characteristic is the drumming with the hind legs on the ground, which can be quite loud and can be heard over several meters.

nutrition

The weevil's diet consists mainly of insects , from which it mainly consumes ants , termites and beetles . The preferred prey includes animals 2 to 5 mm in length. In addition, green parts of plants, fruits and seeds are also part of the menu. According to studies of stomach contents in the eastern coastal forest area of ​​Kenya, the proportion of plant material was a good 4.6%. The invertebrates contained a large number of beetles (22.5%), as well as millipedes , cockroaches and crickets . About 0.9% consisted of other material such as twigs, hair, feathers and stones. In the Arabuko-Sokoke National Park, it was found that the proboscis mainly eats ants, especially during the dry season. The size of the individual territories also varies with the number of ants, so that with a high ant density the extent of the action areas is reduced, the size fluctuations being 10%. In Uganda, analyzes of stomach remains have mostly shown ants. The food is mainly sought by scratching with the hind legs in the leaf waste on the ground, additionally also through the mobile nose and thus with the sense of smell . Depending on the success of the search for food, an animal covers between 10 and 100 m, an average of 40 m in half an hour. The long tongue is used for food intake. The proboscis regularly drinks water, bending its elongated nose upwards.

The trunk rat's body temperature is 33 to 37.5 ° C, which is an average of one degree lower than that of elephant shrews. In contrast, the thermoneutrality of the proboscis compared to the elephant shrews and the species of the genus Macroscelides covers a wide range from 25 to 34 ° C, which reflects the preference for mesian to humid habitats. As a result, the kidneys are not designed to accumulate urine . The consequent high loss of water at high ambient temperatures encountered the trunk rat with the prospect cooler shelters and with vasodilation ( vasodilation ). A torpor at cool outside temperatures, as known from some elephant shrews, does not occur.

Reproduction

Little information is available about the reproduction of the proboscis. It is possible that the females in areas near the equator give birth to offspring all year round, in regions further south the reproductive phase could be restricted. In southern Africa, births usually take place shortly before the onset or during the rainy season, which lasts from August to October, pregnant females have been observed in January, July and October. In eastern Africa, on the other hand, there are sightings of young animals for almost every month. Often only one young is born, sometimes two. According to studies in Zambia, every second female carries two embryos ; in Zimbabwe it was two out of three females. A newborn baby weighs on average 31.5 g and has a head-torso length of around 7.5 cm. It is well developed with fully developed fur, eyes open and capable of running within a very short time (fleeing nest). The daily weight gain is about 2 g. The time of weaning and the onset of sexual maturity have not yet been documented, but, as with other elephants, it should be relatively early. Life expectancy in the wild is unknown; animals can live up to six years and seven months in captivity.

Predators and parasites

Natural predators include the Eastern Gaboon viper , birds of prey and predators, and possibly feral cats . The proboscis usually takes refuge in holes in the ground or trees. External parasites have been identified with various representatives of ticks , such as Ixodes , Rhipicephalus and Haemaphysalis , which often collect at the base of the ear and tail. In addition, with Chimaeropsylla , Neolinognathus , Ctenocephalides and Echidnophaga , several forms of fleas and also some mites occur. In addition, a large number of internal parasites could be detected, including scratchworms such as Cloeascaris , Subulura and Travasospirura and also some blood parasites such as Plasmodium and Trypanosoma .

Systematics

Internal systematics of elephants according to Heritage et al. 2020  Macroscelididae     Macroscelidinae     Macroscelidini    Galegeeska      Petrodromus      Petrosaltator      Macroscelides   Elephantulini    Elephantulus   Rhynchocyoninae    Rhynchocyon

The proboscis is the only species from the monotypical genus Petrodromus . It belongs to the family of elephants (Macroscelididae) within the order of the same name (Macroscelidea). The elephants represent a group of smaller mammals that are endemic to Africa and include a total of six genera and two subfamilies. One of the subfamilies, the Rhynchocyoninae , is formed by the proboscis dog ( Rhynchocyon ) and is therefore also monotypical. They are the largest representatives of the elephants and predominantly inhabit forested habitats . The second subfamily is represented by the Macroscelidinae , which, in addition to the proboscis, also includes the elephant shrews ( Elephantulus ) and the genera Macroscelides , Galegeeska and Petrosaltator . The majority of the representatives of the Macroscelidinae are adapted to significantly drier open landscapes, only the proboscis also occurs in areas with closed vegetation. According to molecular genetic analyzes, the two subfamilies separated in the Lower Oligocene , about 32.8 million years ago. A greater diversification of the Macroscelidinae then began in the Upper Oligocene around 28.5 million years ago. Petrodromus forms together with Patrosaltator , Gelegeeska and Macroscelides the tribe of the Macroscelidini , Elephantulus on the other hand stands alone in the tribe of Elephantulini .

Internal system of elephant shrews according to Smit et al. 2011 (shortened) and the position of the Somali elephant shrew  Elephantulus    Elephantulus fuscus      Elephantulus fuscipes      Galegeeska      " Panelephantulus clade "    Macroscelides      Petrodromus tetradactylus      Petrosaltator      remaining elephant shrews

The position of Petrodromus within the subfamily Macroscelidinae and the resulting close relationship to Elephantulus and Macroscelides could be confirmed by the genetic analyzes. The more precise relationships between the individual representatives turned out to be problematic. In general, the proboscis is closely related to Macroscelides ; there is also a much closer connection to the North African elephant shrew ( Petrosaltator rozeti ) and the Somali elephant shrew ( Galegeeska revoili ); for a long time both were considered to belong to the elephant shrews. The close relationship of the proboscis, especially to the North African elephant shrew, is confirmed not only by molecular genetic evidence but also by morphological and anatomical findings. This can be seen, among other things, in the similar structure of the penis , which in both representatives has two laterally formed lobes near the tip, or in the appearance of mammary glands in male animals. However, there are again differences in the number of pairs of teats , which is generally three in Elephantulus and Macroscelides , but only two in Petrodromus . The proboscis also has similarities in skull structure, which it in turn connects with the North African elephant shrew and the other elephant shrews, while the Macroscelides species differ more here due to the bulging timpani. In the structure of the Basicranium, Macroscelides , Petrodromus and the North African elephant shrew are more in agreement, and all three representatives have an ossified nerve canal on the inner ear. Due to the numerous indications of a closer relationship between Petrodromus and Elephantulus rozeti , as the North African elephant shrew originally called, and Macroscelides , the three taxa were temporarily combined in a common Panelephantulus clade . But this results in a deep embedding of Petrodromus and Macroscelides in the genus Elephantulus , which in turn makes the latter paraphyletic . A necessary reassessment of the Macroscelidinae would offer two options: the merging of the North African elephant shrew and the proboscis into one genus or the unification of all generic representatives of the Macroscelidinae in a single higher-level taxon. In 2016, the North African elephant shrew was finally separated from the genus Elephantulus and placed in its own genus Petrosaltator . At the same time the Panelephantulus clade received the status of a tribe with the name Macroscelidini. Regarding the relationship of the proboscis to the Somali elephant shrew, there were only indications here from genetic studies from 2020, which is why the latter was transferred to the newly created genus Galegeeska . The splitting of the entire family complex of the Macroscelidini dates back to the Lower Miocene around 20.6 million years ago.

The proboscis is very varied, the distinctions are mostly made on the basis of different colors of the fur. The division into subspecies is preliminary, some forms may have to be considered clinical . The following subspecies are usually given:

• P. t. beirae Roberts , 1913; Mozambique south of the Zambezi ; diffuse median strip on the back; Sides of the body light yellowish brown, clearly separated from the whitish belly; no bristle hairs along the midline on the underside of the tail; Upper side of the tail almost naked.
• P. t. rovumae Thomas , 1897; eastern Tanzania , northeastern Mozambique ; no clear median line on the back; whitish belly interspersed with a yellowish brown; Hair along the center line on the underside of the tail like a bristle with a knot-like end.
• P. t. sangi Heller , 1912 (is sometimes also managed within P. t. sultan ); known only from the Taita Mountains of Kenya ; narrow and discreet yellowish-brown lightened central stripe on the back, flanked by gray zones; long, bristle-like hair along the center line on the underside of the tail with a knot-like end, the upper side of the tail almost bare.
• P. t. schwanni Thomas & Wroughton , 1907; known only from Coguno in the province of Inhambane in Mozambique; diffuse, gray median stripe on the back; Body sides gray with a light yellow-brown tinge, blurred to the yellowish-brown belly; bristle-like hairs along the center line on the underside of the tail with a knot-like end.
• P. t. sultan Thomas , 1897; Coastal area of ​​Kenya and Tanzania from Galana to Pangani ; narrow and discreet reddish-brown central stripe on the back, flanked by gray zones; Belly rather yellowish brown; long, bristle-like hairs along the center line on the underside of the tail with a knot-like end, the upper side of the tail almost bare; large shape with top row length over 28 mm.
• P. t. swynnertoni Thomas , 1918; at Chimanimani in Zimbabwe ; matter than P. t. beirae and P. t. tetradactylus ; Tail hardly hairy.
• P. t. tetradactylus Peters , 1846; from the Zambezi northwards via Zambia , Malawi to Tanzania and Rwanda and in the southeast of the Democratic Republic of the Congo ; no clear median line on the back; whitish belly; Hair elongated along the center line on the underside of the tail.
• P. t. tordayi Thomas , 1910; at Sankuru in the Democratic Republic of the Congo; very dark back color without median stripe; conspicuous yellow-brown stripes on the sides of the body; cream-colored belly, partly washed out yellow-brown; Tail almost naked.
• P. t. warreni Thomas , 1918; Zululand in KwaZulu-Natal in South Africa ; no clear median line on the back; Sides of the body gray with very little yellow-brown; whitish belly; Hair along the center line on the underside of the tail unspecialized, tail thinly haired.
• P. t. zanzibarensis Corbet & Neal , 1965; on the islands of Zanzibar and Mafia ; slightly reddish brown central stripe on the back, set off from the yellowish brown sides of the body by gray zones; Hair along the midline of the underside of the tail with a knot-like end; smaller than P. t. sultan with an upper row of teeth less than 28 mm.

Tribal history

There are no known fossils of the proboscis. The close relationship with the North African elephant shrew advocates an early separation of the two from each other. The molecular genetic investigations date this to the end of the Middle Miocene around 11 million years ago. The formation of the Sahara may have played a major role, separating the once more widespread precursors of the two species and thus contributing to their current distribution.

Research history

Wilhelm Peters

The genus and species were first scientifically described by Wilhelm Peters in 1846 . An individual from Tete on the Zambezi in Mozambique, whom he had observed and captured there himself, was available to him for the naming , the place is also considered a type locality. Due to the trunk-like elongated nose and the long hind legs, Peters recognized great similarities between the trunk rat and Macroscelides , and he put both together in the group of "tubers". The difference he noted was the four-toed hind foot. The scientific generic name Petrodromus is made up of the Greek words πέτρα ( petra "rock") and δρομος ( dromos "runner") and refers to the assumption that the animals live in rocky landscapes. The species name tetradactylus is also of Greek origin ( τέσσαρες ( tessares ), derived τετρα ( tetra "four") and δάκτυλος ( daktylos "finger")) and highlights the four-rayed hind feet as a feature. In his report Scientific trip to Mossambique from 1852, Peters then described the proboscis in detail and went into both external and internal anatomical properties, and he named Sena and Boror as additional sites . Albert Günther first drew attention to the knot-like thickening of the hair on the underside of the tail in 1881. In 1897 Oldfield Thomas suspected that the genus Petrodromus could contain several species due to the design or presence or absence of these special tail hair ends. At that time he led P. t. rovumae and P. t. sultan , later also P. t. tordayi as separate species. Other authors followed him in part, so that the genus Petrodromus consisted of several species with different subspecies in the first two decades of the 20th century. In 1916, Ned Hollister created the subgenus Cercoctenus , which he distinguished from Petrodromus on the basis of the shape of the knot-like ends on the tail bristles and the design of the cusps on the premolars. In Cercoctenus he combined the forms P. t. sultan , P. t. sangi and P. t. schwanni . Two years later, Oldfield Thomas discussed bristle-like hair again and established another subgenus, Mesoctenus , into which he added P. t. rovumae posed. In his opinion, the genus Petrodromus consisted of three sub-genera, on the one hand the nominate form with simple, elongated bristles and on the other hand Mesoctenus and Cercoctenus , which were characterized by the special shape of the tips of the bristles, the former only having slight thickenings, the latter being clearly button-like or knot-like Formations. In the overall revision of the elephant in 1968 by Gordon Barclay Corbet and John Hanks , these did not take into account the individual subgenera and combined the different species into one with a total of nine subspecies. However, they stated that P. t. tordayi would be a possible candidate for a separate species that emerged allopatric due to its separate distribution in the Congo Basin without connection to the remaining occurrence of the weevil . However, they could not provide any defining characteristics.

Proboscis and humans

Representations of the proboscis

Unlike many other African mammals that were often depicted in local prehistoric rock art , depictions of the proboscis are virtually unknown. In the vicinity of Springbok in the South African province of North Cape , however, there are a few images of an animal on the dark-colored dolerite blocks of the Karoo , with a large head and elongated nose that reminds one of elephants. Characteristic vertical lines on the underside of the tail are reminiscent of the bristles of the proboscis. The rock paintings are part of the culture of the Khoisan ethnic groups, their age is unknown, but could be up to 6000 years. It is noteworthy that they occur around 1000 to 1200 km west to southwest of the next present-day populations of the weevil. Today the landscape belongs to the semi-arid areas of the Karoo, it is unknown whether the proboscis was originally widespread here as well.

Threat and protection

There are no known major threats to the weevil population. It is one of the most widespread species of elephants and is therefore classified by the IUCN as "not endangered" ( least concern ). It is represented in numerous protected areas, including the Arabuko Sokoke National Park . However, the individual subspecies are exposed to different influences. For the subspecies P. t., Which is restricted to the Taita Mountains in Kenya . sangi is believed to be a greater threat due to the destruction of the forests, possibly it is already extinct. The subspecies P. t. beirae from southeast Africa is generally considered to be very rare. In eastern Kenya, the proboscis is sometimes hunted for food. According to a study from the beginning of the 1990s, the Giriami capture up to 5700 individuals annually with a total biomass of around 1.1 t in the Arabuko-Sokoke forest area of ​​around 350 km². With a share of 35%, the proboscis is the most commonly shot species. According to calculations, the amount corresponds to about 15 individuals per square kilometer per year, which is considered acceptable with a population density of 2.1 to 3.9 individuals per hectare. The proboscis is rarely shown in zoological gardens, was the only holder of European zoo history, in the 1960s, London. However, individual animals are also in private facilities.

literature

• Mark R. Jennings and Galen B. Rathbun: Petrodromus tetradactylus. Mammalian Species 682, 2001, pp. 1–6 ( full text )
• Stephen Heritage: Macroscelididae (Sengis). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 8: Insectivores, Sloths and Colugos. Lynx Edicions, Barcelona 2018, pp. 206-234 (p. 230) ISBN 978-84-16728-08-4
• Ronald M. Nowak: Walker's Mammals of the World. Johns Hopkins University Press, 1999 ISBN 0801857899
• Galen B. Rathbun: Petrodromus tetradactyla Peters, 1846 - Four-toed elephant-shrew. In: John D. Skinner and Christian T. Chimimba (Eds.): The Mammals of the Southern African Subregion. Cambridge University Press, 2005, pp. 24-25
• Galen B. Rathbun: Petrodromus tetradactyla Peters, 1846 - Four-toed elephant-shrew. In: Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold and Jan Kalina (eds.): Mammals of Africa Volume I. Introductory Chapters and Afrotheria. Bloomsbury, London, 2013, pp. 279-281

Individual evidence

1. ↑ ^{a b c d e f} Clare D. FitzGibbon: Comparative ecology of two elephant-shrew species in a Kenyan coastal forest. Mammal Review 25 (1/2), 1995, pp. 19-30
2. ↑ ^{a b c d e f g h i j k} Mark R. Jennings and Galen B. Rathbun: Petrodromus tetradactylus. Mammalian Species 682, 2001, pp. 1-6
3. ↑ ^{a b c d e f g h} Galen B. Rathbun: Petrodromus tetradactyla Four-toed Sengi (Four-toed Elephant-shrew). In: John D. Skinner and Christian T. Chimimba (Eds.): The Mammals of the Southern African Subregion. Cambridge University Press, 2005, pp. 24-25
4. ↑ ^{a b c d e f g h i j k l m} Galen B. Rathbun: Petrodromus tetradactyla Peters, 1846 - Four-toed elephant-shrew. In: Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold and Jan Kalina (eds.): Mammals of Africa Volume I. Introductory Chapters and Afrotheria. Bloomsbury, London, 2013, pp. 279-281
5. ↑ ^{a b c d e f g h i j} Stephen Heritage: Macroscelididae (Sengis). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 8: Insectivores, Sloths and Colugos. Lynx Edicions, Barcelona 2018, pp. 206-234 (p. 230) ISBN 978-84-16728-08-4
6. ^ ^{A b} Wilhelm Peters: Scientific trip to Mossambique: carried out on the orders of His Majesty the King Friedrich Wilhelm IV in the years 1842 to 1848. Berlin, 1852, pp. 1–205 (pp. 92–100) ( [1] )
7. ^ ^{A b} Gea Olbricht and William T. Stanley: The topographic distribution of the penis and mammary glands in sengis (Macroscelidea) and its usefulness for taxonomic distinctions. Zoosystematics and Evolution 85 (2), 2009, 297-303
8. ↑ ^{a b c d} G. B. Corbet and J. Hanks: A revision of the elephant-shrews, Family Macroscelididae. Bulletin of the British Museum (Natural history) Zoology 16, 1968, pp. 47-111
9. ^ Dieter Kock and William T. Stanley: Mammals of Mafia Island, Tanzania. Mammalia 73, 2009, pp. 339-352
10. ↑ ^{a b} N. Oguge, R. Hutterer, R. Odhiambo and W. Verheyen: Diversity and structure of shrew communities in montane forests in Southeast Kenya. Mammalian Biology 69, 2004, pp. 289-301
11. ↑ Hyd Kiwia: species richness and abundance estimates of small mammals in Zararinge coastal forest in Tanzania. Tanzanian Journal of Science 32 (2), 2006, pp. 51-60
12. ↑ K. Kaswera: The ecology and morphology of sengis in DRC. Afrotherian Conservation 6, 2008, pp. 11-12
13. ↑ ^{a b c d e} Katherine H. Oxenham and Michael R. Perrin: The spatial organization of the four-toed elephant-shrew (Petrodromus tetradactylus) in Tembe Elephant Park, KwaZulu-Natal, South Africa. African Zoology 44 (2), 2009, pp. 171-180
14. ↑ ^{a b} C. FitzGibbon, M. Perrin, C. Stuart (IUCN SSC Afrotheria Specialist Group) and H. Smit (Stellenbosch University): Petrodromus tetradactylus. The IUCN Red List of Threatened Species. Version 2014.3. ( [2] ); last accessed on May 26, 2015
15. ^ Galen B. Rathbun: The social structure and ecology of Elephant-shrews. Zeitschrift für Tierpsychologie Beiheft 20 (Advances in Behavioral Research), 1979, pp. 1-76
16. ↑ ^{a b c d e} Ian Linn, Michael R. Perrin and Kay Hiscocks: Use of space by the four-toed elephant-shrew Petrodromus tetradactylus (Macroscelidae) in Kwazulu-Natal (South Africa). Mammalia 71, 2007, pp. 30-39
17. ↑ ^{a b} Galen B. Rathbun: Tales of sengi tails. Afrotherian Conservation 6, 2008, 8-10
18. ↑ ^{a b c} Arthur Loveridge: Notes on East African Mammalia (other than horned ungulates) collected or kept in captivity 1915-1919, part 2. Journal of the East African and Uganda Natural History Society 5 (17), 1922, p. 39 -69
19. ^ Mike Perrin: Comparative aspects of the metabolism and thermal biology of elephant-shrews (Macroscelidea). Mammal Review 25, 1995, pp. 61-78
20. ↑ Colleen T. Downs: Renal structure, and the effect of an insectivorous diet on urine composition of Southern African Elephant-Shrew species (Macroscelidea). Mammalia 60 (4), 1996, pp. 577-589
21. ↑ Colleen T. Downs and Mike R. Perrin: The thermal biology of three Southern African Elephant-shrews. Journal of Thermal Biology 20 (6), pp. 445-450
22. ^ Gea Olbricht: Longevity and fecundity in sengis (Macroscelidea). Afrotherian Conservation 5, 2007, pp. 3-5
23. ↑ Ivan G. Horak, Shaun Welman, Stacey L. Hallam, Heike Lutermann and Nomakwezi Mzilikazi: Ticks of four-toed elephant shrews and Southern African hedgehogs. Onderstepoort Journal of Veterinary Research 78 (1). 2011, Art. 243 doi: 10.4102 / ojvr.v78i1.243
24. ↑ LJ Fourie, JS du Toit, DJ Kok and IG Horak: Arthropod parasites of elephant-shrews, with particular reference of ticks. Mammal Review 25, 1995, pp. 31-37
25. ↑ ^{a b c} Steven Heritage, Houssein Rayaleh, Djama G. Awaleh and Galen B. Rathbun: New records of a lost species and a geographic range expansion for sengis in the Horn of Africa. PeerJ 8, 2020, p. E9652, doi: 10.7717 / peerj.9652
26. ^ Mike Perrin and Galen B. Rathbun: Order Macroscelidea - Sengis (Elephant-shrews). In: Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold and Jan Kalina (eds.): Mammals of Africa Volume I. Introductory Chapters and Afrotheria. Bloomsbury, London, 2013, pp. 258-260
27. ↑ ^{a b c d} H. A. Smit, B. Jansen van Vuuren, PCM O'Brien, M. Ferguson-Smith, F. Yang and TJ Robinson: Phylogenetic relationships of elephant-shrews (Afrotheria, Macroscelididae). Journal of Zoology 284, 2011, pp. 133-143
28. ^ PF Woodall: The penis of elephant shrews (Masmmalia: Macroscelididae). Journal of Zoology 237, 1995, pp. 399-410
29. ↑ Fabiana Panchetti, Massimiliano Scalici, Giuseppe Maria Carpaneto and Giancarlo Gibertini: Shape and size variations in the cranium of elephant-shrews: a morphometric contribution to a phylogenetic debate. Zoomorphology 127, 2008, pp. 69-82
30. ^ ^{A b} Massimiliano Scalici and Fabiana Panchetti: Morphological cranial diversity contributes to phylogeny in soft-furred sengis (Afrotheria, Macroscelidea). Zoology 114, 2011, pp. 85-94
31. ↑ ^{a b c} Julien Benoit, Nick Crumpton, Samuel Merigeaud and Rodolphe Tabuce: Petrosal and Bony Labyrinth Morphology Supports Paraphyly of Elephantulus Within Macroscelididae (Mammalia, Afrotheria). Journal of Mammalian Evolution 21, 2014, pp. 173-193
32. ^ Matjaž Kutner, Laura J. May-Collado and Ingi Agnarsson: Phylogeny and conservation priorities of afrotherian mammals (Afrotheria, Mammalia). Zoologica Scripta 40, 2011, pp. 1-15
33. ↑ John P. Dumbacher, Elizabeth J. Carlen and Galen B. Rathbun: Petrosaltator gen. Nov., A new genus replacement for the North African sengi Elephantulus rozeti (Macroscelidea; Macroscelididae). Zootaxa 4136 (3), 2016, pp. 567-579
34. ↑ Patricia A. Holroyd: Macroscelidea. In: Lars Werdelin and William Joseph Sanders (eds.): Cenozoic Mammals of Africa. University of California Press, Berkeley, London, New York, 2010, pp. 89-98
35. ↑ Christophe J. Douady, François Catzeflis, Jaishree Raman, Mark S. Springer and Michael J. Stanhope: The Sahara as a vicariant agent, and the role of Miocene climatic events, in the diversification of the mammalian order Macroscelidea (elephant shrews). PNAS 100 (14), 2003, pp. 8325-8330
36. ↑ Wilhelm Peters: About new mammalian species from the orders of insect-eaters and rodents. Report on the negotiations of the Royal Prussian Academy of Sciences suitable for publication in 1846, pp. 257–259 ( [3] )
37. ^ Albert Günther: Notes on the species of Rhynchocyon and Petrodromus. Proceedings of the Zoological Society of London, 1881, pp. 163-164 ( [4] )
38. ↑ Oldfield Thomas: Exhibition of small mammals from North Nyasaland, with a note on the genus Petrodromus. Proceedings of the Zoological Society of London, 1897, pp. 430-436 ( [5] )
39. ↑ Oldfield Thomas: New African mammals. Annals and Magazine of Natural History 5, 1910, pp. 83-92 ( [6] )
40. ^ Austin Roberts: The collection of mammals in the Transvaal Museum registered up to the 31st march, 1913, with description of new species. Annals of the Transvaal Museum 4 (2), 1913, pp. 65-107
41. ↑ N. Hollister: Descriptions of a new genus and eight new species of African mammals. Smithsonian miscellaneous collections 66, 1917, pp. 1–8 ( [7] )
42. ↑ Oldfield Thomas: Notes on Petrodromus and Rhynchocyon. The Annals and magazine of natural history 9 (1), 1918, pp. 364-370 ( [8] )
43. ^ Janette Deacon and Craig Foster: My Heart Stands in the Hill. London, Cape Town, Sydney, 2005, pp. 1–191 (p. 135)
44. ↑ Clare D. FitzGibbon, Hezron Mogaka and John H. Fanshawe: Subsistence Hunting in Arabuko-Sokoke Forest, Kenya, and Its Effects on Mamml Populations. Conservation Biology 9 (5), 1995, pp. 1116-1126
45. ↑ Zoo animal list ( [9] ), last accessed on June 15, 2015
46. ↑ Gea Olbricht and Alexander Sliwa: Elephant shrews - the little relatives of elephants? Journal of the Cologne Zoo 53 (3), 2010, pp. 135–147

Web links

Commons : Proboscis  - Collection of images, videos and audio files

• Petrodromus tetradactylus in the Red List of Threatened Species of the IUCN 2013.1. Listed by: FitzGibbon, C., Perrin, M., Stuart, C. (IUCN SSC Afrotheria Specialist Group) & Smit, H. (Stellenbosch University), 2008. Retrieved May 26, 2015.
• California Academy of Sciences: photo of a proboscis rat