As Shark Fest and Shark Week come to a close I thought it might be a nice change of pace to look at a shark that you didn’t see featured in any documentary these last two weeks. When you ask someone to think of a shark, most people will immediately think of the a large, charismatic species like the great white, tiger, or whale shark. It’s understandable as to why. These are large, flashy species that are easily recognizable and attract our attention very easily. These are also species that are highly studied species as they are keystone species within their ecosystems. But when we study sharks, we have to remember that sharks come in all shapes and sizes. So let’s look at one of the smallest shark species in the world, the Dwarf Lanternshark (Etmopterus perryi).
We known very little about the dwarf lanternshark. It is a deepsea shark found in the Caribbean Sea along the coast of Colombia and Venezuela (Skomal, 2016). These sharks are a members of the order Squaliformes, whose sharks are characterized by the appearance of two dorsal fins (some species presenting with dorsal spines) and the lack of an anal fin (Klimley, 2013). Species within this order vary greatly in size from the Greenland Shark, which can reach lengths over 20 feet (2.5 m), all the way down to the dawrf lanternshark, which barely reaches 8 inches (20 cm) in total length (Skomal, 2016)!
As its name suggests, the dwarf lanternshark is one of a few known species of shark to luminesce. Lantern sharks inhabit the mesopelagic and bathypelagic regions of the ocean, where light is very dim or nonexistent in the environment. Well developed luminous organs, called photophores, aid lanternsharks in finding food and possibly communication (Tricas, et al., 1997; Parker, 2008).
Because the dwarf lanternshark is so small and lives at depths of over 1,000 ft (305 m), this species is rarely caught by fisheries (Parker, 2008). Much of their life history and ecology is still a mystery to science. It is unlikely that their secrets will be revealed any time soon!
Authority: Springer & Burgess, 1985
Family: Etmopteridae, 41 species
Length: 8.3 inches (21 cm)
Weight: Maximum weight unknown
Habitat: Continental upper slopes
Depth: 1,000 – 3,000 ft (305 – 915 m)
Gestation: Period unknown
Litter Range: Suspected 2 to 3 pups
Home Range: Caribbean waters from Colombia to Venezuela
IUCN Status: Data Deficient
(Leandro, 2006; Parker, 2008; Skomal, 2016)
The new Ocean For Sharks Shop is open! There’s handmade ocean inspired plush animals, canvas paintings, and of course my children’s book, Winifred the Wondrous Whale Shark, available in print and PDF. Be sure to stop by. Remember proceeds benefit shark research and conservation with a donation to Project AWARE!
As always, remember you can make a difference for marine ecosystems by contacting your Congress man or woman and telling them that you care about the quality of our waters! Sharks, rays, and other marine organisms cannot speak or be represented in Congress. They need your voice. Get involved and stand up for sharks. Until next time finatics!
Featured Image Source
Clark, C. (Photographer). (2007). Dwarf Lanternshark [Digital Image]. Retrieved from https://ocean.si.edu/ocean-life/sharks-rays/dwarf-lantern-shark
Klimley, A. P. (2013). The biology of sharks and rays. University of Chicago Press.
Leandro, L. 2006. Etmopterus perryi. The IUCN Red List of Threatened Species 2006: e.T60240A12332635.
Parker, S. (2008). The encyclopedia of sharks (2nd ed.). Buffalo, NY: Firefly Books Ltd.
Skomal, G. (2016). The Shark Handbook: The Essential Guide for Understanding the Sharks of the World. (2nd ed.). Kennebunkport, ME: Cider Mill Press.
Tricas, T. C., Deacon, K., Last, P., McCosker, J. E., Walker, T. I., & Taylor, L. (1997). The Nature Company Guides: Sharks and Rays. (L. Taylor, Ed.). Hong Kong: The Nature Company, Time Life Books.