Lontra longicaudis (Olfers, 1818)

Voss, Robert S. & Fleck, David W., 2017, Mammalian Diversity And Matses Ethnomammalogy In Amazonian Peru Part 2: Xenarthra, Carnivora, Perissodactyla, Artiodactyla, And Sirenia, Bulletin of the American Museum of Natural History 2017 (417), pp. 1-1 : 1-

Lontra longicaudis (Olfers, 1818)

Figure 15D

VOUCHER MATERIAL (TOTAL = 1): Nuevo San Juan (MUSM 11172).

OTHER INTERFLUVIAL RECORDS: Anguila ( Escobedo-Torres, 2015), Choncó ( Amanzo, 2006), Río Yavarí (Salovaara et al., 2003), Río Yavarí- Mirím (Salovaara et al., 2003), San Pedro (Valqui, 1999), Tapiche ( Jorge and Velazco, 2006).

IDENTIFICATION: Following van Zyll de Jong’s (1972) revision of the Nearctic and Neotropical

river otters (previously treated as congeneric with Old World Lutra ), three subspecies of Lontra longicaudis have been consistently recognized: L. l. annectans (Major, 1897) from Central America and trans-Andean South America, L. l. enudris (Cuvier, 1823) from Amazonia, and L. l. longicaudis (Olfers, 1818) from southeastern Brazil and the La Plata drainage. Analyses of mtDNA sequence data (Trinca et al., 2012) suggest that annectans should perhaps be recognized as a distinct species, but there is evidence of genetic exchange between Amazonian populations (referred to enudris) and La Platan populations (referred to longicaudis ). Although Feijó and Langguth (2013) recently suggested that all the South American subspecies of L. longicaudis (sensu van Zyll de Jong, 1972) be recognized as full species, we prefer to maintain current usage until the reproductive isolation and/or diagnosability of these nominal taxa can be more convincingly established. Cranial measurements of our voucher specimen ( table 13 ) compare closely with those of almost-topotypical specimens of L. l. enudris (from Surinam; Husson, 1978: table 46).

ETHNOBIOLOGY: The name for the Neotropical otter is bosen, which is monomorphemic and widespread in other Panoan languages. There are no archaic synonyms or overdifferentiated varieties.

Otters are not eaten by the Matses, nor are they usually kept as pets.

The spirit of a Neotropical otter can make children ill if their parent looks at one. Contagion by an otter spirit causes high fever, which is treated with certain medicinal plants (“Neotropical otter medicine”). Other medicinal plants effective against sickness caused by giant otters (“giant otter medicine”) are also said to cure contagion by Neotropical otters, suggesting that, despite the lack of any linguistically labeled category for otters and the complete dissimilarity between the Matses names for Lontra longicaudis and Pteronura brasiliensis , the Matses recognize an association between these taxa at some level.

MATSES NATURAL HISTORY: The Neotropical otter has a smooth, slick body, with a somewhat flat tail and a head like a dog’s. Its fur is shiny and gray when wet. The underside of its neck is light-colored. It has thick whiskers. It has short legs and webbed feet with which it cannot run quickly on land.

The Neotropical otter lives along rivers, large and small streams, streams with muddy bottoms or sandy bottoms, and in lakes and flooded forest.

The Neotropical otter is diurnal. It spends much of the day swimming along streams looking for fish. It travels short distances overland to search for fish at other streams. It makes the water in small streams turbid as it chases fish and looks for wolffishes ( Hoplias spp. [ Erythrinidae ]) lying in the streambed. It feels inside submerged hollow logs and under submerged logs for armored catfishes and tëpuşh fish ( Erythrinus erythrinus [ Erythrinidae ]). When it catches a fish, it eats it sitting on a log that is in the water, or on the bank. It makes a loud gnawing sound as it eats. The otter sleeps in the undercut banks of streams, in holes made in the bank by motmots (birds in the family Momotidae ), or other sheltered places along the bank. It does not sleep in the same place every night, and it does not make burrows to sleep in (as it does to give birth). When it sees people it flees quickly, swimming underwater.

Neotropical otters are usually solitary, but they are also found in groups of two or three. When two or three are together, they play by chasing each other and taking fish from each other. The female gives birth to two young in a shallow burrow dug into the bank of a stream or river. She continually goes to catch fish, eats them, and then comes back to suckle her young. When the young get older, she brings fish to the den for them to eat.

No predators eat Neotropical otters.

The Neotropical otter whines, saying “weee weee weee.” It barks saying “kuesak kuesak kuesak.”

The Neotropical otter eats all kinds of fish, including armored catfish, large pimelodid catfishes, tëpuşh ( Erythrinus erythrinus [Erythrini- dae]), pone ( Hoplias spp. [ Erythrinidae ]), and bëdichued ( Leporinus spp. and/or Schizodon spp. [ Anostomidae ]). It also eats crabs and shrimp.

REMARKS: Matses interviews about Neotropical otters are consistent with the results of most published studies of this widespread taxon (e.g., Kasper et al., 2008; Silva, 2010), notably with respect to its fondness for slowmoving benthic prey (such as armored catfish and erythrinids), but Amazonian field studies are almost nonexistent, so these observations also provide novel details of habitat use and behavior that may be peculiar to the local subspecies ( Lontra longicaudis enudris ; see above). Matses accounts that Neotropical otters make transient and opportunistic use of makeshift shelters (including burrows made by other species) is interesting by comparison with the fixed den sites of sympatric giant otters (see below). Another noteworthy point of comparison based on Matses observations of these species is that female Neotropical otters with newborn young in nursery burrows are said to forage for themselves, whereas female giant otters with nursing young are said to be provisioned by the male.

A published range map (Larivière, 1999: fig. 3) that shows Lontra longicaudis as absent throughout most of western Amazonia is inconsistent with the documented presence of this species in the Yavarí-Ucayali interfluve and at many other western Amazonian inventory sites (e.g., Balta, Cocha Cashu/Pakitza; Voss and Emmons, 1996). An accompanying statement that “ Lontra longicaudis favors clear, fast-flowing rivers and streams and may be absent or rare from sluggish, silt-laden lowland rivers,” (Larivière, 1999: 2) is likewise impossible to reconcile with the presence of Neotropical river otters throughout the flat, sedimentary landscapes of western Amazonia where clear, fastflowing rivers and streams are virtually nonexistent, and where this species is known to forage in lentic habitats (e.g., oxbow lakes and flooded forest).

Figures

FIG. 15. Adult skulls of five sympatric mustelid species illustrating taxonomic differences in size and shape: Galictis vittata (A, MUSM 15157), Eira barbara (B, MUSM 13149), Mustela africana (C, AMNH 61813), Pteronura brasiliensis (D, AMNH 74431), Lontra longicaudis (E, AMNH 98589). All illustrated specimens are from eastern Peru, but only MUSM 13149 and MUSM 15157 are from the Yavarí-Ucayali interfluve.