Question: Neomonachus is a genus of earless seals, within the family Phocidae, it contains two species, the extinct Caribbean monk seal,and which extant endangered species of earless seal in the family Phocidae that is endemic to the Hawaiian Islands? 

Context paragraphs:
Baikal seal: The Baikal seal, Lake Baikal seal or nerpa ("Pusa sibirica"), is a species of earless seal endemic to Lake Baikal in Siberia, Russia.  Like the Caspian seal, it is related to the Arctic ringed seal.  The Baikal seal is one of the smallest true seals and the only exclusively freshwater pinniped species.  A subpopulation of inland harbour seals living in the Hudson's Bay region of Quebec, Canada ("lac de loups marins" harbour seals), the Saimaa ringed seal (a ringed seal subspecies) and the Ladoga seal (a ringed seal subspecies) are found in fresh water, but these are part of species that also have marine populations.  It remains a scientific mystery how the seals originally came to Lake Baikal, hundreds of kilometers from any ocean.

Pinniped: Pinnipeds ( ) (from Latin "pinna" "fin" and "pes, pedis" "foot"), commonly known as seals, are a widely distributed and diverse clade of carnivorous, fin-footed, semiaquatic marine mammals.  They comprise the extant families Odobenidae (whose only living member is the walrus), Otariidae (the eared seals: sea lions and fur seals), and Phocidae (the earless seals, or true seals).  There are 33 extant species of pinnipeds, and more than 50 extinct species have been described from fossils.  While seals were historically thought to have descended from two ancestral lines, molecular evidence supports them as a monophyletic lineage (descended from one ancestral line).  Pinnipeds belong to the order Carnivora and their closest living relatives are bears and musteloids (weasels, raccoons, skunks, and red pandas), having diverged about 50 million years ago.

Phoca: Phoca is a genus of the earless seals, within the family Phocidae.  It now contains just two species, the common seal and the spotted seal (or largha seal).  Several species formerly listed under this genus have been split into the genera "Pusa", "Pagophilus", and "Histriophoca".  For this reason, the fossil history of the genus is unclear, and it has formerly been used as wastebasket taxon for a number of fossils of uncertain affinity.

Neomonachus: Neomonachus is a genus of earless seals, within the family Phocidae.  It contains two species, the extant Hawaiian monk seal and the extinct Caribbean monk seal.  Prior to 2014, all three species of monk seals were placed in the genus Monachus, but that was found to be paraphyletic.

Earless seal: The earless seals or true seals are one of the three main groups of mammals within the seal lineage, Pinnipedia.  All true seals are members of the family Phocidae .  They are sometimes called crawling seals to distinguish them from the fur seals and sea lions of the family Otariidae.  Seals live in the oceans of both hemispheres and, with the exception of the more tropical monk seals, are mostly confined to polar, subpolar, and temperate climates.  The Baikal seal is the only species of exclusively freshwater seal.

Leopard seal: The leopard seal ("Hydrurga leptonyx"), also referred to as the sea leopard, is the second largest species of seal in the Antarctic (after the southern elephant seal).  Along with all of the other earless seals, it belongs to the family Phocidae, and is the only species in the genus Hydrurga.  The name "hydrurga" means "water worker" and "leptonyx" is the Greek for "small clawed".  It is second only to the killer whale among Antarctica's top predators.

Monk seal: Monk seals are earless seals of the tribe Monachini.  They are the only earless seals found in tropical climates.  There are two genera of monk seals, "Monachus" and "Neomonachus", comprising three species: the Mediterranean monk seal, "Monachus monachus"; the Hawaiian monk seal, "Neomonachus schauinslandi"; and the Caribbean monk seal, "Neomonachus tropicalis", which became extinct in the 20th century.  The two surviving species are now rare and in imminent danger of extinction.  All three monk seal species were classified in genus "Monachus" until 2014, when the Caribbean and Hawaiian species were placed into a new genus, "Neomonachus".

Pusa: Pusa is a genus of the earless seals, within the family Phocidae.  The three species of this genus were split from the genus "Phoca", and some sources still give "Phoca" as an acceptable synonym for "Pusa".

Caribbean monk seal: The Caribbean monk seal, West Indian seal or sea wolf (as early explorers referred to it), "Neomonachus tropicalis", was a species of seal native to the Caribbean and is now believed to be extinct.  The Caribbean monk seals' main predators were sharks and humans. Overhunting of the seals for oil, and overfishing of their food sources, are the established reasons for the seals' extinction.  The last confirmed sighting of the Caribbean Monk Seal was in 1952 at Serranilla Bank, between Jamaica and Nicaragua.  In 1994 the species was officially declared extinct in the United States of America after an exhaustive search for the seals which lasted for about five years.  This analysis was conducted by the National Oceanic and Atmospheric Administration and the National Marine Fisheries Service.  Caribbean monk seals were closely related to the Hawaiian monk seals, which live around the Hawaiian Islands and are now endangered, and Mediterranean monk seals, another endangered species.  An estimated 600 Mediterranean monk seals and 1,100 Hawaiian monk seals are alive in the wild.

Hawaiian monk seal: The Hawaiian monk seal, "Neomonachus schauinslandi" (formerly "Monachus schauinslandi"), is an endangered species of earless seal in the family Phocidae that is endemic to the Hawaiian Islands.

Supporting paragraphs: Neomonachus Hawaiian monk seal
Answer: Hawaiian monk seal