Proechimys oconnelli, J. A. Allen, 1913

Don E. Wilson, Thomas E. Lacher, Jr & Russell A. Mittermeier, 2016, Echimyidae, Handbook of the Mammals of the World – Volume 6 Lagomorphs and Rodents I, Barcelona: Lynx Edicions, pp. 552-604 : 572

37.

O’Connell’s Spiny-rat

Proechimys oconnelli

French: Rat-épineux d'O’Connell / German: O'Connell-Kurzstachelratte / Spanish: Rata espinosa de O'Connell

Taxonomy. Proechimys oconnelli J. A. Allen, 1913 ,

“Villavicencio (alt. 1600 ft.), [Meta,] Colombia.”

Proechimys oconnelli is a member of the semispinosus-species group. Monotypic.

Distribution. C Colombia (headwaters of Meta and Guaviare rivers E of E Andes Range).

Descriptive notes. Head-body 250 mm, tail 175 mm. No specific data are available for body weight. O’Connell’s Spiny-rat is moderately large-bodied, with medium length tail (c.70% of head—body length). Dorsal color is orange rufous, finely lined with black, paler on sides than mid-back and rump. Venter is pure white, sharply defined against color of sides. Pale inner thigh stripe is continuous across ankle onto dorsal surface of hindfoot, which is two-toned, pale cream on inner one-half and light brown on outer one-half, with dark color typically extending to fourth andfifth toes. Plantar pads are moderate in size, with thenar and hypothenar sub-equal. Tail is sharply bicolored, dark brown above and creamy white below, and thinly clothed with short, fine hairs. Visible scale annuli are relatively wide, averaging 9 annuli/cm along mid-length oftail. Pelage is neither distinctly nor heavily spiny because aristiforms are weakly developed, long (18-21 mm) and thin (0-8-0-9 mm), and tipped with long whip-like filament. Skull of O’Connell’s Spinyrat is unremarkable, with elongated and tapering rostrum. Temporal ridge is either non-existent or only weakly developed, extending posteriorly from supraorbital ledge onto parietals. In this aspect, O’Connell’s Spiny-rat contrasts sharply with its presumptive sister species, Tomes’s Spiny-rat ( P. semispinosus ). Post-orbital process of zygoma is obsolete but formed completely by jugal. Incisive foramina are angular to lyrate in shape, with moderately developed posterolateral flanges that extend onto anterior palate forming grooves on either side of midline and despite only moderate development of maxillary keel and median palatal ridge. Premaxillary part of septum is well developed and elongated, encompassing more than one-half the opening; premaxillary part is well developed and always in contact with premaxillary part; and vomer is completely encased and notvisible in ventral aspect. Floor of infraorbital foramen has obvious groove formed by distinct lateral flange that supports passage of maxillary nerve. Mesopterygoid fossa is moderate in width, with angle averaging 63°, and penetrates to middle of M?. Upper and lower cheekteeth are simplified, with three folds on each upper tooth and dP, and 2-3 folds on lower molars. Counterfold pattern is 3-3-3-3/3-(2)-(2)-2(3). Baculum of O’Connell’s Spiny-rat is of medium length (length 8:2-8-4 mm) but broad (proximal width 4-9 mm; distal width 4-4-5-3 mm), similar to that of Tomes’s Spiny-rat in its blunt and thickened base but without distal apical extensions. Chromosomal complement is 2n = 32 and FN = 52.

Habitat. Cis-Andean tropical evergreen forest on eastern slopes of the Eastern Andes Range and Sierra de Macarena at elevations of 170-700 m.

Food and Feeding. There is no information available for this species.

Breeding. There is no information available for this species.

Activity patterns. There is no specific information available for this species, but O’Connell’s Spiny-rat is presumably nocturnal.

Movements, Home range and Social organization. There is no information available for this species.

Status and Conservation. Classified as Data Deficient on The IUCN Red List. Lack of published studies on biology of O’Connell’s Spiny-rat underscores need for fieldwork designed to understand local abundance, habitat requirements, and potential threats before a proper conservation status can be identified.

Bibliography. Allen (1913), Eisenberg (1989), Emmons (1990, 1997a), Gardner & Emmons (1984), Hershkovitz (1948), Patton (1987), Patton & Gardner (1972), Patton & Leite (2015), Patton & Reig (1989), Tate (1939), Woods (1993), Woods & Kilpatrick (2005).

Figures

12. Broad-headed Spiny-rat (Clyomys laticeps), 13. Guiara (Euryzygomatomys spinosus), 14. White-spined Spiny-rat (Irinomys albispinus), 15. Elias’s Spiny-rat (Trinomys eliasi), 16. Rigid-spined Atlantic Spiny-rat (Trinomys paratus), 17. Yonenaga’s Spiny-rat (Trinomys yonenagae), 18. Elegant-spined Atlantic Spiny-rat (Trinomys setosus), 19. Moojen’s Spiny-rat (Trinomys moojeni), 20. Pau Brasil Spiny-rat (Trinomys mirapitanga), 21. Rio de Janeiro Spiny-rat (Trinomys dimidiatus), 22. Sao Paulo Spiny-rat (Trinomys thering), 23. Gracile Atlantic Spiny-rat (Trinomys gratiosus), 24. Sao Lourenco Punare (Thrichomys laurentius), 25. Jacobina Punare (Thrichomys inermis), 26. Lagoa Santa Punare (Thrichomys apereoides), 27. Pantanal Punare (Thrichomys pachyurus), 28. Foster’s Punare (Thrichomys fosteri), 29. Painted Tree-rat (Callistomys pictus), 30. Coypu (Myocastor coypus), 31. Armored Rat (Hoplomys gymnurus)

Distribution. C Colombia (headwaters of Meta and Guaviare rivers E of E Andes Range).