Dunn's Mud Turtle
Kinosternon dunni
Summary 2
Dunn's mud turtle (Kinosternon dunni) or the Colombian mud turtle is a species of turtle in the Kinosternidae family. The epithet or specific name honors Emmett Reid Dunn, an American herpetologist. It is endemic to Colombia.
Dunn’s Mud Turtle, Kinosternon dunni (Family Kinosternidae), is a medium-sized aquatic turtle (carapace length to at least 180 mm) found in streams and marshes in the Río Baudó, Río Docampadó, Río San Juan, and Río Atrato drainage basins of the Departamento del Chocó in western Colombia. It is most similar and closely related to K. angustipons from Central America, and belongs to the K. leucostomum species group. Very little is known of the natural history of this species. It is apparently carnivorous and probably highly aquatic. It may reproduce nearly year-round, laying multiple clutches of one or two eggs each. A field survey of each of the four inhabited basins is urgently needed to assess the population status of this species. Because of its restricted range and apparent rarity, and because it is eaten locally, it could be more threatened than currently recognized.
Diagnosis 3
Dunn’s Mud Turtle is one of the largest kinosternid turtles, with males reaching at least 180 mm carapace length and females up to 166 mm (Forero-Medina et al., 2012). Males average larger in size than females, with males reaching up to 800 g body weight and females up to
595 g. The carapace of the adult is brown and unkeeled, or with a weak median keel. The first vertebral scute is relatively wide, contacting the second marginal scutes. The plastron is small relative to the carapace (plastral forelobe posterior width is less than 40%, and plastral hindlobe anterior width is less than 35% of maximum carapace length). The plastron has a posterior, medial notch and two distinct transverse hinges that border the central fixed portion of the plastron the adult appear in Schmidt (1947), Medem (1961, 1962), Legler (1965), Pritchard (1979), Iverson (1981), Ernst and Barbour (1989), Schilde (2001), Castaño-Mora and Medem (2002), Ministerio del Medio Ambiente (2002), Vetter (2005), Corredor-Londoño et al. (2007), Rueda-Almonacid et al. (2007), Forero-Medina et al. (2012), and Rentería-Moreno et al. (2012).
Distribution 3
This species was previously known from only approximately ten localities in the Departamento del Chocó near the Pacific coast of western Colombia (Medem 1961, 1962; Iverson 1992; Castaño-Mora 1997; Ceballos-Fonseca 2000; Castaño-Mora et al. 2004). These
localities lie in the Pacific drainage basins of the Ríos Baudó, Docampadó, and San Juan. However, a recent survey found the species at two localities in the southern portion of the drainage basin of the Río Atrato (Rentería-Moreno et al. 2012), which flows northwards into the Caribbean in the Gulf of Urabá. This extends the range of the species to this new drainage, and suggests that it may also occur in more localities in the lower (northern) Atrato region, as had been suggested by Medem (1961).
Besides these confirmed localities in the southern Río Atrato drainage basin, there is also a new record corresponding to a specimen deposited in the museum of the Instituto Alexander von Humboldt, from Acandí, Chocó, in a small drainage in the Gulf of Urabá (Rentería-Moreno et al. 2012). The specimen was collected in 1988 in a rice field and may represent a natural occurrence.
Corredor-Londoño et al. (2006, 2007) and Castro- Herrera and Vargas-Salinas (2008) speculated that this turtle may also range into the northern Departamento del Valle del Cauca, which includes a portion of the lower Río San Juan drainage, although there are no confirmed records of the species in this area.
Habitat and Ecology 3
Kinosternon dunni is the most poorly known species of kinosternid turtle. Chocoan rainforest people informed Medem (1961) that the species preferred small streams, especially their headwaters, but that it was also found in marshy areas. They seemed to think that it must be well-adapted for a terrestrial existence; however, other kinosternids with such a reduced plastron tend to be highly aquatic.
In a recent survey in the Río Atrato (Rentería-Moreno et al. 2012), most individuals were captured in a marshy area dominated by palm trees of the genus Euterpe. Animals were active during the night, and were all captured in water of < 1.5 m depth. One individual was captured in a small stream 3–5 m wide, with a depth that varied more than 1.5 m during a rain event. The sex ratio of the collection was 7:9:1 (males:females:juveniles).
Very little is known of the biology of this species; what is known was reported by Medem (1961, 1962). Natives told Medem that it reproduces throughout the year. His single female died in captivity and upon dissection was found to contain two shelled eggs (45 x 25 mm and 44 x 25 mm) and one enlarged ovarian follicle 15 mm in diameter. This suggests that multiple clutches are laid, but that clutch size may only be one or two eggs. All kinosternid species studied to date exhibit temperature-dependent sex determination (Ewert et
al. 2004), and hence it is likely that K. dunni does also.
Conservation 3
Status: Vu (Vulnerable) IUCN 2017-2
http://www.iucnredlist.org/details/11008/0
IUCN 2012 Red List Status: Vulnerable (VU B1+2c; assessed 1996, needs updating); TFTSG Draft Red List: Vulnerable; CITES: Not Listed; Colombian Red Data Book: Vulnerable.
Subspecies 3
No subspecies have been described.
Sources and Credits 3
Iverson, J.B., Carr, J.L., Castaño-Mora, O.V., Galvis-Rizo, C.A., Rentería-Moreno, L.E., and Forero-Medina, G. 2012. Kinosternon dunni Schmidt 1947 – Dunn’s Mud Turtle, Cabeza de Trozo. In: Rhodin, A.G.J., Pritchard, P.C.H., van Dijk, P.P., Saumure, R.A., Buhlmann, K.A., Iverson, J.B., and Mittermeier, R.A. (Eds.). Conservation Biology of Freshwater Turtles and Tortoises: A Compilation Project of the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group. Chelonian Research Monographs No. 5, pp. 067.1–067.5, doi:10.3854/crm.5.067.dunni.v1.2012, http://www.iucn-tftsg.org/cbftt/.
http://www.iucn-tftsg.org/wp-content/uploads/file/Accounts/crm_5_067_dunni_v1_2012.pdf
Fuentes y Créditos
- (c) Gabriel Camilo Jaramillo Giraldo, algunos derechos reservados (CC BY-NC-SA), subido por Gabriel Camilo Jaramillo Giraldo
- Adaptado por Gabriel Camilo Jaramillo Giraldo de un trabajo de (c) Wikipedia, algunos derechos reservados (CC BY-SA), http://en.wikipedia.org/wiki/Kinosternon_dunni
- (c) Gabriel Camilo Jaramillo Giraldo, algunos derechos reservados (CC BY-SA)
