Recently described species in the family of Nurse sharks

The Pacific Nurse shark, Ginglymostoma unami, is a shark belonging to the family Ginglymostomatidae. It is found in southeastern coast of Baja California, Mexico to Costa Rica including Gulf of California. It was recently described in 2015, so not much is known, and it is not evaluated yet.


Family: Ginglymostomatidae – Nurse Sharks

Genus: Ginglymostoma 

Species: unami


Phylum– Chordata

Class– Chondrichthyles


Common NameCarpet Sharks

Family– Ginglymostomatidae

Common NameNurse Sharks




Average Size and Length: They have been measured at 207 cm/ 6.8 feet.

Teeth and Jaw: The teeth morphology differs in the Pacific Nurse shark and the Nurse shark, but the teeth are serrated and small. Their mouths are small and terminal with large cavities. Check out this video of the mouth, teeth and nasoral barbels.

Head: The head is broad. They have long, nasoral grooves with nasal barbels. The eyes have small spiracles behind them.

Denticles: The Pacific Nurse shark also differs from the Nurse shark in the form and number of keels on the dermal denticles.

Tail: The caudal fin is elongated.

Demographic, Distribution, Habitat, Environment and Range: The Pacific Nurse shark is found in southeastern coast of Baja California, Mexico to Costa Rica including Gulf of California. They are considered tropical benthopelagic.

Diet: They are opportunistic and eat a variety of bottom dwelling prey.

Ram-Suction Index: Nurse sharks are obligate suction feeders capable of generating suction forces that are among the highest recorded for any aquatic vertebrate to date. They may also shake their head violently to rip off smaller, digestible sizes of prey, or suck and spit.

Aesthetic Identification: The Pacific Nurse shark differs from the Nurse shark (Ginglymostoma cirratum) between posterior end of the second dorsal fin and the beginning of the caudal lobe, both being shorter. Also, by the position of the insertion of the first dorsal fin with regard to the pelvic fins. The Pacific Nurse is yellowish brownish in color. Both spineless dorsal fins are rounded. The pectoral fins are muscular.

Biology and Reproduction: Not much is known, but they are more than likely ovoviviparous. More than likely they live between 20-25 years, but this is not confirmed.

Behavioral Traits, Sensing and Intelligence: More than likely, like their other family members, they are solitary nocturnal, and possibly group with others during the day. They rest at the bottom, searching for food in the sediments.

Speed: Their top speed is unknown, but some have reported up to 25 mph, but this may not be accurate. More than likely they are sluggish.

Pacific Nurse Shark Future and Conservation: This species is not yet evaluated.

Pacific Nurse Shark Recorded Attacks on Humans: More than likely they are similar to other family members in that they do not pose a threat to humans, but will bite and defend themselves if threatened or provoked. They have strong suction, and do not let go so their bites can pack a lasting and powerful punch.

Moral-Flores, L.F.D., Ramírez-Antonio, E., Angulo, A. & Pérez-Ponce de León, G. (2015). “Ginglymostoma unami sp. nov. (Chondrichthyes: Orectolobiformes: Ginglymostomatidae): a new species of nurse shark from the Tropical Eastern Pacific“. Revista Mexicana de Biodiversidad. 86: 48–58.