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JOHNSON'S SEA GRASS 



Common Name: JOHNSON'S SEA GRASS 

 Scientific Name: Halophila johnsonii 



Species Status: Proposed as Threatened 



Species Trend: N/A 



Current Estimated Population: N/A 



SPECIES POPULATION STATUS 



Johnson's seagrass has a very Hmited distribution and it is the least abundant seagrass within its 

 range. The species is only known to reproduce asexually and may be limited in distribution 

 because of this characteristic. It plays a major role in the viability of benthic resources and has 

 been documented as a food source for endangered West Indian manatees and threatened green 

 sea turtles. NMFS is continuing to conduct ecological research on the species to better 

 understand its life histor\' and to use in conservation decisions affecting the seagrass ecosystems. 



SPECIES BIOLOGY 



Identifying characteristics of Johnson's seagrass include smooth marginated. spatulate foliage 

 leaves in pairs 0-5-2.5 cm long, a creeping rhizome with petioles, sessile (attached to their bases) 

 female flowers, and longnecked fruits. The male flowers are unknown. Outstanding differences 

 between Johnson's seagrass and other similar species are its distinct asexual reproductive 

 characteristics, and leaf morphology. It has a major role in the viability of benthic resources. 



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