New species alert: giant air-breathing Amazonian fish

Prof. Stewart with A. leptosoma.
Photo credit: SUNY-ESF

Professor Donald Stewart, from my Alma-mater the State University New York College of Environmental Science & Forestry (Syracuse, NY), has recently described a new fish species Arapaima leptosoma (Osteoglossomorpha: Osteoglossidae), the first new arapaima species since 1847 (Copeia, 2013).  Research funding for describing this new species was provided in part by National Geographic and SUNY-ESF.

Arapaima is a genus of large-sized (up to 2.5 m and 200 kg) freshwater fish found in South America.  The new species name, derived from Greek, refers to the organism's relatively slender ("lepto") body ("soma").  

Arapaima via ESF.edu

Three traits helped identify this organism as a distinct species: 
1) Shape of the dorsal sensory cavity,
2) Underlying bone structure of the head which makes the head relatively flat,
3) Dorsal fin sheath covering anterior dorsal rays.

Listen to this interview from Northeastern Public Radio (WAMC) of Prof. Stewart describing how the new species was identified. 

Arapaima live in backwater areas of the Amazon rainforest, these waters are often oxygen-poor, which makes their primitive air-breathing lung an advantageous trait.

Indigenous peoples have long depended on arapaima as a food source.  With new knowledge of arapaima species diversity, biologists are becoming concerned about species conservation, particularly because not enough information is known regarding their spatial distribution and abundance.  Charismatic mega-fauna, particularly those hunted for sport, are especially vulnerable to the threats of over fishing.

New omnivorous mammal species describe in the Americas!

An omnivorous mammal species found in the Americas was recently described – the first new omnivorous mammal species to be described in 35 years!   The olinguito (Bassaricyon neblina), a member of the raccoon family (Procyonidae), is indigenous the high-altitude cloud forests of Ecuador and Columbia (map below).  

(Olinguito habitat range (red) and sitings (black dots)
by National Museum of Natural History, via Smithsonian.com)

(Olinguito by Mark Gurney via Smithsonian.com)

The mystery specimen:

("A comparison of olinguito skulls (far right) with those of other
olingos shows their smaller size and slightly different shape."
By Lauren Helgen via Smithsonian.com)

Kristofer Helgen and his team at the Smithsonian National Museum stumbled upon the new species as they worked with clarify known species of olingos (Bassaricyon spp.).  The mysterious specimens differed compared to know species in their fur color (reddish vs. grey), fur length (long vs. short, comparatively), and the elevations at which the specimens were collected (high vs. low).  Olinguitos are also smaller than their olingos kin - hence, their suffix–“ito”, translating as "little" in Spanish. 

To the field!

(Andes Cloud Forest by Slack12 via Flickr CC)

Kristofer Helgen and colleagues observed this new species in its native cloud forest habitat, where they learned it is primarily nocturnal and arboreal, with a diet comprised largely of tree fruit and some insects.  Read more about this neat species at Smithsonian.com.

 

(Andes cloud forest by D. J. Rosen via Flickr CC)