Megalomys Trouessart 1881

Wilson, Don E. & Reeder, DeeAnn, 2005, Order Rodentia - Family Cricetidae, Mammal Species of the World: a Taxonomic and Geographic Reference (3 rd Edition), Volume 2, Baltimore: The Johns Hopkins University Press, pp. 955-1189 : 1124

Megalomys Trouessart 1881

Megalomys Trouessart 1881 , Le Naturaliste, 1: 357.

Type Species: Mus pilorides Desmarest 1826

Synonyms: Moschomys Trouessart 1903 ; Moschophoromys Elliot 1904 .

Species and subspecies: 2 species:

Species Megalomys desmarestii (Fischer 1829)

Species Megalomys luciae Major 1901

Discussion: Oryzomyini . Derived postcranial traits of Megalomys are consistent with its association within Sigmodontinae sensu stricto (lack of entepicondylar foramen, tuberculum of 1 st rib contacting both the 1 st thoracic and 7 th cervical vertebrae; as per M. desmarestii, BMNH 1850.11.30.6); other cranial characters more narrowly point to its membership within Oryzomyini (long palate with prominent posterolateral pits, absence of alisphenoid strut; as per M. luciae, BMNH 53.12.16.2, and M. desmarestii, BMNH 50.11.30.6 and 55.12.24.201), as diagnosed by Voss and Carleton (1993). A combination of features suggests that the close relatives of Megalomys may be sought among certain derived oryzomyines, such as Oryzomys sensu stricto , or Nectomys (e.g., thenar and hypothenar pads present but barely indicated; molars brachyodont and pentalophodont, with M1/m1 four-rooted; supraorbital and temporal ridging well developed and reflected dorsally; carotid circulation derived).

Named as a subgenus of the all-inclusive Hesperomys , later associated with Holochilus by Thomas (1884) or Oryzomys by Major (1901), and subsequently recognized as an oryzomyine genus endemic to the Lesser Antilles ( Ellerman, 1941; Hall, 1981; Steadman and Ray, 1982; Tate, 1932 c). Does not include the extinct Galápagos endemic curoi, described as a species of Megalomys by Niethammer (1964); see Steadman and Ray (1982) and account of Megaoryzomys . Morphology redescribed and taxonomy revised by Ray (1962) as a subgenus of Oryzomys , following the undeveloped opinions of Osgood (1947) and Hershkovitz (1948 b). The four nominal species (audreyae Hopwood, 1926; curazensis Hooijer, 1959; desmarestii Fischer, 1829 ; luciae Forsyth Major, 1901 ) are extinct, possibly all due to anthropogenic causes, but M. desmarestii and M. luciae , listed below, persisted into the middle, perhaps late, 1800s ( Ray, 1962; Woods, 1989). Known from Pleistocene-Holocene fossils, Pre-Columbian midden deposits, and a few modern specimens ( Ray, 1962). See G. M. Allen (1942) for compilation of meagre historical accounts .