Grey Four-eyed OpossumPhilander opossum Size: body=30 cm; tail=30 cm; weight=750 g Description: Medium-sized, slender; greyish above, cream-yellow below, with a conspicuous white spot over each eye. Prehensile tail blackish with a contrasting white tip. Activity: Nocturnal, terrestrial and arboreal. Habits: Solitary. This agile opossum is commonly seen foraging along stream banks. When startled, it often climbs low branches in trees or brush, where it sits and stares at the observer. Often raids garbage pits in camps. Habitat: Forest, secondary brush, and clearings, especially near the edges of small creeks and streams. Signs: Tracks with five toes on each foot; the widely splayed, opposable big toe on the hind foot is clearly evident. Status: Common. Distribution in Iwokrama

Common OpossumDidelphis marsupialis Creole name: Stink opossum Size: body=35 cm; tail=35 cm; weight=1.5 kg Description: Largest opossum: long, coarse, black guard hairs overlay soft yellow or cream underfur, lending an overall mottled, dirty appearance. Ears large, black, and naked. The long tail mostly naked with basal one-third to one-half black, and the tip white. Face and cheeks pale cream or yellowish orange with a blackish line between ears extending to the eyes. Whiskers black. Eyeshine bright reddish. Activity: Nocturnal, terrestrial, semi-arboreal. Habits: Solitary, omnivorous. It may be seen climbing trees or roaming along on the forest floor and in clearings. This large opossum forages widely, usually on the ground, for a variety of small animals, fruits, carrion, or nearly anything even remotely edible. Usually nests in hollow trees or tangles of vines, but may also den in burrows on or below ground. Commonly raids garbage dumps and will pick bats out of mist nets. Habitat: Primary and secondary forest. Also around buildings near forest. Signs: Large tracks (50 to 60 mm) with widely splayed, opposable big toe on hind foot clearly visible. Distinctive odour produced by anal scent glands. This opossum is often smelled before it is seen, (hence local name “stink opossum”). If grabbed by the scruff of the neck, it will twirl its tail like a helicopter while urinating and defecating, spraying its foul smelling faeces to deter predators and curious humans. Status: Locally common in Iwokrama, although numbers fluctuate between years. Distribution in Iwokrama

Water OpossumChironectes minimus Size: body=30 cm; tail=35 cm; weight=675 g Description: A medium-sized, sleek opossum with a bold pattern of patches of silvery grey and black on the back. Tail naked and black with a short white tip. Hind feet conspicuously webbed. Front feet unwebbed, with an elongated bone in the wrist, appearing to form an extra digit. Both males and females have a pouch. If seen well, this handsome, strikingly marked opossum is unmistakable. Eyeshine bright red. Activity: Nocturnal, terrestrial, and semi-aquatic. Habits: Solitary. The water opossum is aptly named. It is usually seen while searching for food in or near small, rocky streams, although it also occurs in other aquatic habitats. This carnivorous species feeds on fish, crustaceans, and other invertebrates that it catches in the water. When startled, it usually jumps into water to escape. Nests in burrows in stream banks. Habitat: Small rivers and streams and other bodies of water in forested areas. Never found far from water. Signs: Tracks with five toes on each foot, front feet unwebbed, hind feet obviously webbed, in good impressions. Big toe not widely splayed to the side as it is in other opossums. Status: Apparently uncommon in Iwokrama.

Murine Mouse OpossumMarmosa murina Size: body=12 cm; tail=30 cm; weight=40 g Description: Small sized: relatively short fur; back and head greyish or reddish brown; cheeks and belly salmon-coloured or pinkish (not white) and not contrasting strongly with colour of back and sides; prominent black eye-ring. Long naked, prehensile tail. Female does not have a pouch. Eyeshine bright red. Activity: Nocturnal, arboreal and terrestrial. Habits: Solitary, it mainly eats insects. Forages in low vines and on the forest floor for insects and the occasional fruit. It is most commonly found up to 3 metres above ground. When approached closely (and deliberately) it will freeze motionless in the beam of a light to the point that it can even be petted. Habitat: One of the most common mouse-opossums in secondary forest and near clearings. Often found near the edges of streams, in dense vegetation and in vine tangles. Sometimes enters houses and buildings at the edge of forest. Status: Locally common in Iwokrama. Distribution in Iwokrama

Woolly Mouse OpossumMicoureus demerarae Size: body= 18 cm; tail= 23 cm; weight= 100 g Description: Largest mouse opossum: fur long and woolly; back and head greyish- brown; cheeks orangish and belly greyish-orange or yellow; prominent black eye ring. The long tail is furred for 25-50 mm from its base; naked portion of the tail dark brown with a mottled white tip. Female does not have a pouch. Eyeshine bright red. Activity: Nocturnal, mainly arboreal in understory or sub canopy. Habits: Usually solitary, eats insects, small vertebrates and fruit. Common in dense viney vegetation along the edges of streams. Usually build nests in vine tangles or crowns of palms. Habitat: Primary and secondary forest, especially dense viney vegetation along the edges of streams. Like the Murine Opossum they will inhabit houses in forested areas. Status: Common in Iwokrama. Distribution in Iwokrama

Delicate Mouse OpossumMarmosops parvidens Size: body= 10 cm; tail= 15 cm; weight= 20 g Description: Tiny mouse opossum: fur relatively short; back and head velvety-brown; cheeks and belly greyish white; darkish eye ring usually present; feet white. Naked ears large and conspicuous. The arms and legs are noticeably long, thin and delicate. The long tail is naked and uniform brown. Female does not have a pouch. Activity: Nocturnal, arboreal and terrestrial. Habits: Solitary, eats insects and fruit. Found near the ground in the understory of open forest, sometimes on small fallen branches or saplings. Typically slow moving and deliberate. Habitat: Primary terra firme forest. Status: Uncommon. Distribution in Iwokrama

Short-tailed OpossumMonodelphis brevicaudata Size: body= 16 cm; tail= 9 cm; weight= 100 g Description: Only small terrestrial opossum in Guyana with a short tail: back and top of head with a broad band of silvery dark grey or black, contrasting sharply with deep reddish on sides of body and throat; feet black. Short, blackish tail furred for one-third to one-half its length. Relatively short, broad muzzle. Female does not have a pouch. Activity: Diurnal, mainly terrestrial. Habits: Solitary, insectivorous. Usually travels on the ground, but it also runs on top of fallen logs and occasionally climbs in small trees. Habitat: Mature and secondary forest, and in gardens. Usually found in upland forest away from streams. Status: Apparently uncommon in Iwokrama. Distribution in Iwokrama