About Ototylomys phyllotis Merriam, 1901
Common and Scientific Name
This species, commonly called the big-eared climbing rat, has the scientific name Ototylomys phyllotis Merriam, 1901.
Taxonomic Classification
It belongs to the order Rodentia and the family Cricetidae, and it is the most widely distributed species in the genus Ototylomys. A second species in this genus was described in 2017, from the Mexican state of Chiapas.
Genus Origin
The genus Ototylomys originated 3.35 million years ago, before the Great American Biotic Interchange, and the genus first appeared near Honduras and El Salvador.
Genus Name Etymology
The genus name Ototylomys comes from Greek words: otus meaning ear, tylos meaning knob, knot, or swelling, and mus meaning mouse. This name refers to the species’ large ears and shelf-like skull.
Body Form and Coloration
The big-eared climbing rat is a slender rat with two-toned coloration: dark fur on the upper part of its body and lighter fur on the underside.
Head Features
It has large eyes and large, hairless ears.
Tail Characteristics
It also has a long, hairless, scaled tail.
Geographic Variation in Traits
The species’ size and color vary across its geographic range. Most populations have a creamy white underbelly, but populations in Mexico and Guatemala have a slate-colored underbelly.
Skull Morphology
The top of this species’ skull is flat, and it has a prominent interparietal bone and supraorbital ridges.
Sexual Dimorphism
There is no sexual dimorphism in this species.
Geographic Distribution
This species has a distribution ranging from Mexico to Costa Rica.
