Narke =paralysis Numbfish

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1 Narke =paralysis Numbfish
Narcinidae Narke =paralysis Numbfish

2 Characteristics Round flat disc w/ soft edges no denticles or thorns
Large spiracles Prominent caudal fin 1st dorsal fin =2nd dorsal fin Mouth tubular and protractile Bioelectrogenesis in electric organs behind eyes for sensing and stunning prey 8-37 volts Accessory electric organ electroplaques Nocturnal

3 Family Narcinidae 9 genera w/ 40 spp. (last three often included in separate family) Benthobatis –blind rays 3 spp. Crassinarke – sleeper torpedo 1 spp. Diplobatis- painted ray 4 spp. Discopyge –Apron ray Heteronarce –soft electric ray Narcine – lesser electric ray 19 spp. Narke Temera Typhlonarke 2 spp.

4 New species 2003 Benthobatis yangi 2003 Narcine atzi
2002 Narcine insolita 2002 Narcine oculifera 2001 Narcine leoparda

5 distribution Sandy or muddy shallow waters
Atlantic Pacific Indian Ocean Temperate to subtropical waters Narcine -circumtropical concentrated in Indo-West Pacific Benthobatis -Atlantic and Indian Diplobatis -E. Pacific and W. Atlantic Discopyge- S.W. Atlantic and S.E. Pacific Crassinarke- W. North Pacific Heteronarce –W. and C. Indian Ocean

6 Diplobatis ommata

7 Narcine brasiliensis

8 Crassinarke dormitor– sleeper torpedo

9 Diplobatis pictus- painted ray

10 Discopyge tschudii –Apron ray

11 Feeding Tubular mouth extended to suck up benthic prey
Polychaete worms Crustaceans Small teleosts anemones

12 Reproduction Ovoviviparous Nourished w/ yolk them histotroph
Young born w/ ability to produce electrical charge

13 IUCN red list Bycatch of bottom trawl fisheries Fish meal
2 spp. Off S. America Discopyge tschudii – neat threatened Narcine leoparda – near threatened 6 spp. listed as vulnerable Benthobatis kreffti, 4 spp. Of Diplobatis

14 Lesser electric ray Narcine brasiliensis
Distributed in shallow W. Atlantic; common in Gulf of Mexico Color varies from brown to orange w/ rings or ovals on dorsal surface Disc width 20cm, length 45 cm 17-34 tooth rows in each jaw Conical, and sharp

15 Lesser electric ray

16 Lesser electric ray