Subfamily Dendromurinae
African climbing mice, fat mice, tree mice, and relatives

Dendromurinae is an Old World subfamily of terrestrial and arboreal mouse-like rodents in the family Nesomyidae. There are 24 dendromurine species in six genera. (Musser and Carleton, 2005)

Dendromurines are native to sub-saharan Africa. (Carleton and Musser, 1984)

Dendromurines live in dry or wet grasslands, scrublands, sandy plains, savannahs, alpine and subalpine habitats, forests, swamps, agricultural fields, and floodplain woodlands. They live at elevations from sea level to 4,300 meters. (Carleton and Musser, 1984; Nowak, 1999)

Dendromurines have been classified as murids (Alston 1876, Thomas 1896, Miller and Gidley 1918, Ellerman 1941, Carleton and Musser 1984, Musser and Carleton 1993), cricetids (Allen 1939) or as a separate family, Dendromuridae (Chaline et al. 1977). Molecular studies based on LCAT and vWF genes (Michaux et al. 2001), IRBP gene sequences (Jansa and Weksler 2004), and GHR, BRCA1, RAG1, and c-myc genes (Steppan et al. 2004) all show that dendromurines fall within a clade outside of either cricetids or murids, and this clade is now recoginzed as the family Nesomyidae. Cricetomyines seem to be the sister group to dendromurines (Michaux et al. 2001, Jansa and Weksler 2004, Steppan et al. 2004), and these two subfamilies are estimated to have diverged between 13.5 and 15.3 million years ago (Steppan et al. 2004).

In 1876, Alston grouped the genera Dendromus, Steatomys, and Lophuromys, and he called this grouping Dendromyinae. Thomas revised this classification in 1896, removing Lophuromys from the group and including Leimacomys, Deomys, and Malacothrix. Allen (1939) renamed the group Dendromurinae, and added the genera Petromyscus, Beamys, and Saccostomus. Ellerman (1941) excluded these latter two, as well as Deomys, but added Prionomys to the subfamily. Since then, most authors have recognized Petromyscus as a separate group, but included Deomys and Leimacomys in Dendromurinae (Carleton and Musser 1984, Musser and Carleton 1993). However, molecular phylogenetic analyses have clearly shown that Deomys does not cluster with dendromurines (Michaux et al. 2001, Jansa and Weksler 2004, Steppan et al. 2004); rather, Deomys is a murid and clusters with Lophuromys, Uranomys, and Acomys in the subfamily Deomyinae. Leimacomys has not been included in molecular analyses, but as Musser and Carleton (2005) note, it does not have much in common with dendromurines or any other muroid group, besides molar occlusal patterns, and so they place Leimacomys in its own subfamily. (Allen, 1939; Alston, 1876; Carleton and Musser, 1984; Chaline, Mein, and Petter, 1977; Ellerman, 1941; Jansa and Weksler, 2004; Michaux, Reyes, and Catzeflis, 2001; Miller and Gidley, 1918; Musser and Carleton, 1993; Musser and Carleton, 2005; Steppan, Adkins, and Anderson, 2004; Thomas, 1896)

Dendromurines are small, mouse-like rodents. They range from 50 mm to 145 mm in head and body length, their tails range from 28 to 132 mm, and they weigh 5 to 70 grams. The body is very thick with layers of fat in some species. Dendromurine fur is soft and woolly, long and silky, or short, dense, and velvety. They are gray, brown, reddish or pinkish on the dorsal surface and gray, yellowish, white, or light brown below. There may be black stripes on the back. The tail is sometimes bicolored, usually long and scantily-haired, and is semi-prehensile in some species. The ears are prominent and rounded. Most dendromurines have long, narrow hind feet which are modified for terrestrial, scansorial, or arboreal locomotion.

The dental formula of dendromurines is 1/1, 0/0, 0/0, 3/3 = 16. The incisors are orthodont, opisthodont, or proodont, and the molars are rooted and cuspidate. There is a posterior cingulum on the first and second lower molars. Dendromurines have long, shallow dentaries and long rostrums. The infraorbital foramina are quite wide, and there is an accessory foramen ovale. The middle lacerate formina are small. There is a large, conspicuous tubercle for the origin of the superficial masseter. The lateral surface of the alisphenoid canal is formed from a strut of the alisphenoid bone. (Carleton and Musser, 1984; Nowak, 1999)

Dendromurines live to be three to four years old in captivity. Data on lifespan in the wild is lacking, but it is undoubtedly somewhat shorter. (Carey and Judge, 2002)

Dendromurines are terrestrial or arboreal nocturnal rodents. Some species aestivate during the dry season when food is scarce, living off fat reserves. Dendromurines are either social and tolerant of one another, living peacefully in groups, or solitary and territorial. They build globular nests out of vegetation in tall trees, low shrubs, or underground burrows. Dendromurine burrows range from about 30 to 120 cm deep and often have multiple escape routes. Some species cover over old bird nests and use these for nesting. (Carleton and Musser, 1984; Nowak, 1999)

Dendromurines perceive their environment through vision, hearing, olfaction, taste, and touch, but there is no available information on the relative importance of these senses or on their modes of communication.

Dendromurines are herbivorous, carnivorous, or omnivorous. Some species primarily eat green vegetable matter, others eat only ants. Most have more varied diets, and consume seeds, nuts, fruits, buds, insects, lizards, and bird eggs and nestlings. (Carleton and Musser, 1984; Nowak, 1999)

Predators on dendromurines include owls, snakes, and mammalian carnivores. They are likely to take advantage of their nocturnal habits, agility, and vigilance to avoid predation. (Carleton and Musser, 1984)

Dendromurines are primary, secondary, and tertiary consumers, and they are food for animals at higher trophic levels. Dendromurines are parasitized by several flea species, including Nosopsyllus incisus, Dinopsyllus grypurus, D. lypusus, Leptopsylla algira, Ctenophthalmus verutus, C. evidens, and Xenopsylla bantorum. (Hubbard, 1972; Nowak, 1999)

Dendromurines may carry the plague in some areas. (Hubbard, 1972)

Some dendromurine species are considered a delicacy and are eaten by native peoples. (Nowak, 1999)

The IUCN currently lists one dendromurine species as critically endangered (Mt. Kahuzi climbing mice, Dendromus kahuziensis), three as vulnerable (Lovat's climbing mice, Dendromus lovati, Cameroon climbing mice, Dendromus oreas, and Jackson's fat mice, Steatomys jacksoni), and four as data deficient (Vernay's climbing mice, Dendromus vernayi, velvet climbing mice, Dendroprionomys rousseloti, Nikolaus' mice, Megadendromus nikolausi, and Dollman's tree mice, Prionomys batesi). Several species in this subfamily are rare endemics, making them especially vulnerable to habitat loss. (IUCN, 2004)