A Review of thePattonomys/ToromysClade (Rodentia: Echimyidae), with Descriptions of a NewToromysSpecies and a New Genus

Abstract

New phylogenomic analyses of South American arboreal echimyids show that there are three species within the genus Toromys (T. grandis, T. rhipidurus, and T. sp. nov.) and that the genera Pattonomys and Toromys form a clade that is the sister group to the other three genera of arboreal Echimyini (Echimys, Makalata, and Phyllomys). The arboreal echimyid species Pattonomys occasius is deeply divergent from other species of Pattonomys and from members of other extant named genera, although it shares a sister relationship with Toromys. We erect a new genus, Leiuromys, for it. To clarify the relationships among the species within these three genera, we describe them with molecular and morphological characters. Because most members of these genera have never been reviewed or diagnosed at the species level, we do so now, and we describe a new species, Toromys albiventris, from the upper Ucayali basin of Peru. We illustrate taxa and morphological features not before figured in publications.

First records of Peruvian Toro, Toromys rhipidurus Thomas, 1928 (Rodentia, Echimyidae), in Colombia

“…Feet are grayish above, and the plantar foot is dark brown. The traits and color pattern of the spiny rats in the photos match the description and photographs of the Peruvian Toro, T. rhipidurus, in Emmons and Fabre (2018). Toromys rhipidurus can be differentiated from its Amazonian congeners by the size and pelage color, T. grandis is bigger and has dark, soft pelage on the whole body, including the feet (Iack-Ximenes et al 2005).…”

“…The habitat was a flooded Várzea forest into Tarapoto Lake near the Amazon River. To identify the species, we compared external traits of the rats observed in the pictures with the other species of the Echimyidae family, based on Emmons and Fabre (2018) and Emmons et al (2015). To show the distribution of this species, we plotted the localities provided by Emmons and Fabre (2018), for specimens from Peru, and the new records for Colombia (Table 1; Fig.…”

“…Toromys rhipidurus can be differentiated from its Amazonian congeners by the size and pelage color, T. grandis is bigger and has dark, soft pelage on the whole body, including the feet (Iack-Ximenes et al 2005). Also, T. albiventris has pronounced white underparts, the dorsum is brown-agouti with rusty behind the shoulders to rump, and the feet are grayish-brown above; this species is only known from two localities, "Yarinacocha" and "Suaya", on the Ucayali River in Perú (Emmons and Fabre 2018). Similarly, T. rhipidurus differs from other genera within Echimyidae, including Makalata Husson, 1978 and Dactylomys I. Geoffroy Saint-Hilaire, 1838, which have their tail with short and black hairs exposing the skin.…”

“…The genus Toromys Iack-Ximenes, de Vivo & Perce-quillo, 2005 (Echimyidae, Echimyinae) has a restricted distribution in riverine forests along the line of the Central Amazonian region and the lower reaches of its tributaries in Brazil and Peru (Emmons et al 2015;Emmons and Fabre 2018). This genus includes three species: T. grandis Wagner, 1845, distributed in the Brazilian Amazonia with 16 known localities along both sides of the lower Rio Amazonas, from near its confluence with the Rio Negro to Ilha Caviana at its mouth (Emmons et al 2015); T. albiventris Emmons & Fabre, 2018, which has been recently described and is known from two localities in Peru, "Yarinacocha" and "Suaya" (Emmons and Fabre 2018); and T. rhipidurus Thomas, 1928 known only from northern Peru in the western Amazon Basin (Emmons et al 2015). Despite the distribution of T. rhipidurus at the north-ern Peruvian Amazon, it has never been recorded in Colombia (Fig.…”

“…Isothrix bistriata Wagner, 1845 and I. negrensis Thomas, 1920 have facial stripes and a bicolored tail. Echimys saturnus Thomas, 1928 has black Historical localities of Toromys rhipidurus, Peruvian Toro, specimens in Peru (1-10) fromEmmons and Fabre (2018) and three new records from Colombia (11-13).…”