Stuart's antechinus, Macleay's marsupial mouse
The brown antechinus (Antechinus stuartii ), also known as Stuart's antechinus and Macleay's marsupial mouse, is a species of small carnivorous marsupial of the family Dasyuridae. The males die after their first breeding season, and the species holds the world record for being the world's smallest semelparous mammal.
Brown antechinus are small marsupials. These animals are mostly light brown above, including the upper surfaces of their feet, and a lighter brown below and on their tail. Their coat is short, dense, and coarse. Tails are moderately furred, ears are relatively large and eyes are dark brown.
The Brown antechinus is found east of the Great Dividing Range in Australia, from southeastern Queensland to around Kioloa, New South Wales. This species inhabits forested habitats, with dense lower ground cover and low fire frequency.
Brown antechinus are mostly nocturnal and is arboreal. During warm periods these marsupials live in solitary nests and occupy their own home ranges. As temperatures drop, both males and females stay together in nests with up to 18 animals. Their nests are not stable and antechinus may change nests. Females usually nest alone to rear young. They can separate their offspring between nests in different trees. During winter times Brown antechinus can slip into a torpor which lasts a few hours to lower their metabolic requirements.
Little is known about the mating system in Brown antechinus. Males leave their foraging ranges when mating season begins and gather in all-male nests during most of the night. Females remain solitary but visit male aggregations. During mating season males become vocal, emitting staccato chirps, and become very aggressive. The gestation period lasts for 26-35 days. The litter size is 6-7 young. After birth babies cling to the mother's underbelly and are dragged across the ground while she forages for about 5 weeks. They stay with the mother for about 90 days and leave with the arrival of winter. Brown antechinus reach reproductive maturity in 9-10 months. Like all antechinuses, males die after their first breeding season as a result of stress and exhaustion.
There are no major threats to the Brown antechinus.
The IUCN Red List and other sources do not provide the Brown antechinus total population size, but this animal is one of the most common and widespread species throughout its known range. Currently, the Brown antechinus is classified as Least Concern (LC) on the IUCN Red List and its numbers today remain stable.