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Order: Pristiophoriformes Family: Pristiophoridae (Sawsharks). Etymology: Greek, pristis= “saw”. Pliotrema P. warreni (Sixgill sawshark). Pristiophorus P. Cirratus (Longnose shark) P. japonicus (Japanese sawshark) P. nudipinnis (Shortnose sawshark)
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Order: PristiophoriformesFamily: Pristiophoridae (Sawsharks) Etymology: Greek, pristis= “saw”
Pliotrema P. warreni (Sixgill sawshark) Pristiophorus P. Cirratus (Longnose shark) P. japonicus (Japanese sawshark) P. nudipinnis (Shortnose sawshark) P. schroderi (Bahamas sawshark) 4 undescribed species Taxonomy 2 genera, 5 species
5-6 gill slits Large spiracles behind eyes 2 large dorsal fins (no spines) Somewhat long dorsal lobe on caudal fin (no ventral lobe) General Characteristics
Small sharks, <2 m Benthic/benthopelagic, up to & > 366 m Sawlike snout=rostrum Rostral barbels on ventral side of snout Teeth replaced (unlike sawfish) when lost, alternate sizes General Characteristics
Sawfish • Superorder: Batoidea • Order: Pristiformes • Family: Pristidae • Much larger maximum size • No barbels • Evenly sized teeth • Gill slits on undersurface
Diagnostic Featuresususa;;y distinguished by teeth count • Pliotrema warreni- Sixgill sawshark • 6 pairs of gill openings • Found in W. Indian Ocean (SE coast of S. Africa)
Pristiophorus cirratus- Longnose sawshark • 9-10 teeth in front of barbels, 9 behind • 1st dorsal origin behind rear tips of pectorals • Found in W. Pacific (Australia, Philippines?)
Pristiophorus japonicus- Japanese sawshark • 15-26 teeth in front of barbels, 9-17+ behind • 1st dorsal origin behind rear tip of pectorals • Found in W. Pacific
Pristiophorus nudipinnis- Shortnose sawshark • 13 teeth in front of barbels, 6 behind • 1st dorsal opposite free rear tips of pectorals • Found in S. Pacific (southern shelf of Australia)
Pristiophorus schroederi- Bahamas sawshark • 13-14 teeth in front of barbels, 9-10 behind • 1st dorsal opposite free rear tips of pectorals • Found in W. Atlantic (region btwn. Cuba, FL, and Bahamas)
Reproduction/Life Span • Ovoviviparous- 7-17 pups (average of 10) • Gestation ~ 12 months • Reach maturity ~ 2 years • Parents provide food and protection during post-birth (duration unknown, 1.5 years?) • Breed seasonally, every two years • Have been known to live up to 15 years in wild
Habitat/Food Habits • 640-950 m in and around cont’l & insular shelves & upper slopes • Feed on , shrimp, squids, & crustaceans • Cruise along bottom using barbels & ampullae of Lorenzini on saw to detect prey in mud or sand • Attack prey w/ side to side swipes of the saw
Commercial Value/Predators • Longnose sawshark and Shortnose sawshark caught commercially off Australia • Japanese sawfish highly valued for making “kamaboko”- tradional Japanese fishcake • Humans are main predator (trawl fishing), also larger sharks
Bibliography • Carrier, J.C., et. al. 2004. Biology of Sharks and Their Relatives. CRC Press, Boca Raton, FL. p. 55 • Castro, J.I. 1983. The sharks of North American waters. Texas A&M University Press, College Station, TX. pp.35-36. • Compagno, L.J. 1984. FAO species catalogue. Vol. 4. Sharks of the World. An annotated and illustrated catalogue of shark species known to date. Part 1- Hexanchiformes to Lamniformes. FAO Fish. Synop. 125(4/1): 1-249. • Krcmaric, D. and K. Francl. 2006. "Pristiophorus cirratus" (On-line), Animal Diversity Web. Accessed September 16, 2007 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Pristiophorus_cirratus.html. • Martin, R. Aidan. 2003. Copyright and Usage Policy. World Wide Web Publication, • Retrieved September 16th, 2007 from: http://www.elasmo-research.org/education/shark_profiles/pristiophoriformes.htm. • Slaughter, B. & Springer, S. 1968. Replacement of Rostral Teeth in Sawfishes and • Sawsharks. Copeia Vol 1968 (#3- 8/3)1. pp:499-506.