SUMMARY:The Golden Lion Tamarin (Leontopithecus rosalia) is an endemic primate of the Brazilian Atlantic coastal rainforest, still under serious extinction risk. Just a few is know about its anatomy, specifically the muscle unions. Due to the reasons exposed before, aiming understanding the locomotion of this and others primates, we decided to study the morphology and morphometry of the gracilis and sartorius muscles, and the relation between them, in three Leontopithecus species.The current study examined 18 adult animal carcasses, of both sexes and with no physical abnormalities on the studied region. The material belongs to the Rio de Janeiro Primatology Center collection. The posterior members were dissected till the gracilis and sartorius muscles level, when were executed the morphometry, obtaining the cross section area and the histological analysis of the macroscopic between the gracilis muscle and the sartorius muscle.We described the morphology of the gracilis muscle and sartorius muscle, obtained the average muscle morphometry values and studied, histologically, the union between these muscles.The morphological and morphometric analysis allow us suggest descriptive parameters for these muscles the histological analysis allow us conclude the gracilis muscle and sartorius muscle fibers are not linked, but kept together by a conjunctive tissue, thus, being inserted into the medial side of the tibia. Functionally, we believe the gracilis muscle and the sartorius muscle shall contribute on the active containment of the knee joint and on the biomechanics of the posterior members, of these primates, known as runners. 216 muscles, in the general mobility and locomotion of these animals. These facts leaded us to study the morphology, macro and microscopic, of the muscle union found on the Leontopithecus.
MATERIAL AND METHODThe studied samples numbered 18 carcasses, from adult animals, considering the presence of the molar teeth Hershkovitz (1977). Three Leontopithecus species were used: rosalia (Golden Lion Tamarin), chrysomelas (Golden Headed Lion Tamarin) and chrysopygus (Black Lion Tamarin), all captive bred, of both sexes and with no visual deformations, belonging to the Rio de Janeiro Primatology Center (CPRJ-FEEMA) collection.The biometry of these animals was executed after death in order to obtain the measures and the data were recorded on a proper model. Afterwards, the animals were stored immerse in a formol solution (15%), backwards down, with anterior and posterior members abducted and deflexed Coimbra-Filho, (1985) (Fig. 1).After fixing the carcass in a table, in the position used for conservation, the dissection started with plans through a longitudinal and a anterior incision, at the medial portion of the thigh, and through two more transverse incisions: one at the anterior superior iliac spine level and another one at the tibia tuberosity. After fascia removal, the muscles were visualized and individualized (Fig. 2).Muscle Morphometry: The muscle morphometry was achieved obtaining the following m...