Image Key > Copepoda > Calanoida > Paracalanus indicus

• Male: 0.85-1.02 mm.
• Female: 0.85-0.95 mm.

• Cephalosome is rounded anteriorly.
• Head and pedigerous segment 1 are fused.
• 5th pereiopods reduced and terminate in a spine (Bradford 1978, Bradford-Grieve 1999).

• Caudal rami twice as long as wide.
• Anal segment longer than urosome segment 4.
• Antenna 1 extends to about the distal border of urosome segment 2.

• Fusion line between pedigerous segments 4 and 5 is evident on the dorsal side.
• Genital segment widest anteriorly in dorsal view.
• Caudal rami twice as long as wide with its inner seta short.
• 1st antenna extends just beyond the anal segment, all segments separate.

• Mainly found in coastal waters from temperate to tropical regions but has been reported from the mid-Tasman Sea (Bradford - Grieve 1999). South of Tasmania as P. parvus (Vervoort 1957), south-eastern Australian waters as P. parvus (Dakin and Colefax 1933, 1940, Kott 1957). South-eastern Tasmania as P. parvus (Nyan Taw 1978).
• Along with Acartia tranteri, this species often dominates temperate estuarine waters, as well as shelf waters off the east coast of Australia (Nyan Taw 1978, Kimmerer and McKinnon 1985, Swadling and Bayly 1997).

• Suspension feeders that cannot tolerate the high particulate loads found in some shallow estuaries, and in those cases are often out-competed by Acartia tranteri.
• Predation rate on Paracalnus indicus by small planktivorous fish is approximately twice that of Acartia tranteri, especially in shallow waters where seagrass beds are prominent.
• Appears that Paracalanus indicus has greater visibility and lesser ability to avoid capture than Acartia tranteri (Kimmerer and McKinnon 1987).