Acartia tranteri is a species of marine copepod

Copepod

Copepods are a group of small crustaceans found in the sea and nearly every freshwater habitat. Some species are planktonic , some are benthic , and some continental species may live in limno-terrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests,...

 belonging to the family Acartiidae

Acartiidae

Acartiidae is a family of calanoid copepods distinguishable by the rostral margin not being extended. They are epipelagic, planktonic animals, not being found below a depth of . There are over 100 described species distributed throughout the world's oceans, mainly in temperate areas....

. This Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

n species is related to the New Zealand

New Zealand

New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

 species A. ensifera

Acartia ensifera

Acartia ensifera is a species of marine copepod belonging to the family Acartiidae. This is a slender copepod, around 0.8 - 0.9 mm in length, with distinctively long caudal rami. It is found around the coasts of New Zealand .-References:*...

, A. jilletti

Acartia jilletti

Acartia jilletti is a species of marine copepod belonging to the family Acartiidae. This species has a total length of up to 1 mm. It is very similar to Acartia ensifera but the female can be distinguished by the shorter caudal rami and the male by the relative length of spines on the fifth...

and A. simplex

Acartia simplex

Acartia simplex is a species of marine copepod belonging to the family Acartiidae. This species, just under 1 mm in length, is rather similar to Acartia ensifera but can be distinguished by the presence of spines on the dorsal part of the posterior body segment . Like A. ensifera, it is found...

but can be distinguished by the lack of any ventral prominence posterior to the genital opening in the female and the presence of posterior spines on the metasome (body segment) of the male . It is found off the coast of New South Wales

New South Wales

New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...

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