Indriidae

Indri ( Indri indri )

The Indriartigen ( Indriidae ) are a primate family from the group of lemurs. They comprise three living genera - Wollmakis, sifaka and indri, which are summarized as Indriinae, as well as the extinct groups of Palaeopropithecinae and Archaeolemurinae.

Features

In terms of body size, the members of this family differ considerably. So the Wollmakis reach a body length 25-30 centimeters and a weight of 0.6 to 1.6 kg, while the Indri with up to 90 centimeters in body length and weighing up to 10 kilograms, the largest living lemur is. The extinct representatives, however, were in some cases significantly greater, Archaeoindris reached a weight of up to 200 kilograms. A common feature of Indriartigen is the loss of an incisor per half of the jaw in the lower jaw, so that the occurring in almost all lemurs tooth comb is formed of only four rather than six teeth. The dental formula is: I2/1-C1/1-P2/2-M3/3, a total of 30 teeth. The upper incisors are enlarged, extended the upper canine teeth and sharp. The coat is long and often soft, ranges in color from off-white over gray brown to black, some species are patterned. In their physique, the groups have adapted to different lifestyles: the Indriinae have greatly extended hind legs and are so specialized for jumping locomotion. The first toe is enlarged, the other four toes are connected by a fold of skin and thus form a unit which may be compared with the first toe and allows a firm grip on the road. Your hands are long and thin, and the thumb can not be compared properly to the other fingers. The tail is at the Wollmakis and Sifakas as long as or longer than the hull, while the Indri lemur is the only tailless. The Palaeopropithecinae exhibited greatly prolonged arms and are sometimes compared to their physique with sloths. The Archaeolemuridae were partially adapted to a ground-dwelling lifestyle and therein exhibited similarities with the baboons.

Dissemination

Indriartige live like all lemurs only on the island of Madagascar. They inhabit both the dry forests of the west coast and the rain forests of the east coast, in the central -forested highlands they are missing, however.

Way of life

All kinds of Indriinae are tree dwellers who occasionally come to the ground. They move in the branches vertical climbing and jumping on, on the ground they hop with the hind legs and holding his arms in the air. Unlike most lemurs, the Indriartigen are diurnal, only the Wollmakis have - presumably secondary - adapted to a nocturnal lifestyle. All species build nests no, but sleep on crotches. They live in groups of two to 15 animals, these are either family groups with an adult pair ( at the Wollmakis ) or groups of several males and females as well as the common pups. There are territorial animals, the areas are marked with glandular secretions and sometimes with sounds.

Indriartige are herbivores, which leaves often constitute the main component of their diet. To varying degrees, they also take fruits, buds, flowers and other plant parts to himself. The composition of the diet may also vary according to habitat and season. Occasionally, they feed at the bottom earth, this may serve to provide them with trace elements or neutralize the toxins contained in the leaves. Like many other leaf-eating mammals they compensate the low nutritional value of their food with long rest periods.

Females and males live mostly in long-term monogamous relationships. Usually at the end of the dry season comes after four-to five-month gestation period usually a single young is born. This grows in contrast to many other lemurs not in a nest on, but is carried by the mother at first, and later at the belly on her back. After a few months it is weaned, but there is still some time in his native group.

Endangering

Many species are threatened in their existence. The reasons for this are firstly the destruction of their habitat by fire clearing, logging, charcoal production or mining, the other in the hunting. Some species such as the Indri were indeed protected from taboo reasons before hunting through resettlement and loss of traditions such protection falls, however, more and more away.

The extinction of Palaeopropithecinae and Archaeolemurinae is probably with the human colonization of Madagascar in context, although climatic reasons might have been involved. The island was first settled around 1500 years ago by people, and following numerous large animals are gone.

System

The Indriartigen be classified in the sub- order of the lemurs ( Lemuriformes ), their sister group are probably the ordinary Makis.

They are divided into three subfamilies, two of which are extinct.

• Subfamily Indriinae Wollmakis ( Avahi ) Western Woolly Lemur ( Avahi occidentalis)
• Northwestern Woolly Lemur or Sambirano Woolly Lemur ( Avahi unicolor)
• Cleese Woolly Lemur ( Avahi cleesei )
• Eastern Woolly Lemur ( Avahi laniger )
• Moore Woolly Lemur ( Avahi mooreorum )
• Betsileo Woolly Lemur ( Avahi betsileo )
• Peyrieras - Woolly Lemur ( Avahi peyrierasi )
• Ramanantsoavana - Woolly Lemur ( Avahi ramanantsoavani )
• Southern Woolly Lemur ( Avahi meridionalis )

• Silky Sifaka ( Propithecus candidus )
• Diademsifaka ( Propithecus diadema )
• Edwards' Sifaka ( Propithecus edwardsi )
• Perrier 's sifaka ( Propithecus perrieri )
• Coquerel Sifaka ( Propithecus coquereli )
• From - the - ceiling Sifaka ( Propithecus deckenii )
• Kronensifaka ( Propithecus coronatus )
• Verreaux's Sifaka ( Propithecus verreauxi )
• Goldkronensifaka or Tattersall 's Sifaka ( Propithecus tattersalli )

• Indri ( Indri indri )

• Mesopropithecus †
• Babakotia †
• Palaeopropithecus †
• Archaeoindris †

• Archaeolemur †
• Hadropithecus †

Within the Indriinae the Wollmakis form the sister group of a common taxon of sifaka and indri, the lineage relationships within the extinct representatives are not known.