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UTAS Home > IMAS Home > Image Key > Copepoda > Cyclopoida > Corycaeidae >  Ditrichocorycaeus andrewsi

Ditrichocorycaeus andrewsi

Farran (1911)

Download a fact sheet for Ditrichocorycaeus andrewsi (PDF 454KB)


Phylum Arthropoda
Subphylum Crustacea
Class Maxillopoda
Subclass Copepoda
Order Cyclopoida
Family Corycaeidae
Genus Ditrichocorycaeus
Species andrewsi


  • Female: 0.65-1.07 mm
  • Male: 0.65-1.04 mm

Distinguishing characters

  • Peg like endopod of P4 with 2 setae and a small posterior projection
  • Proportional length of urosome somites and caudal rami
  • Female with short caudal rami compared to other female Ditrichocorycaeus
  • Male has oval genital somite with small ventral hook


  • Prosome 1.5 times as long as urosome
  • Caudal rami as long as anal somite
  • Slight swelling on sides of second pedigerous somite
  • Genital somite broad oval, 4/5 as wide as long
  • Small ventral hook
  • Anal somite as long as wide
  • Caudal rami 4 times as long as wide at proximal end
  • Prosome points extend to 1/3 of genital somite


  • Prosome 2 times as long as urosome
  • Cephalosome separate from 1st pedigerous somite
  • 3rd pedigerous somite with wing-like projections
  • Prosome points extend to less than middle of genital somite
  • Caudal rami just shorter than anal somite and half as long as genital somite
  • 2 groups of fine hairs on genital somite when viewed laterally
  • No ventral hook


  • Epipelagic
  • Coastal and oceanic
  • Subtropical and tropical
  • Indian and Pacific oceans


  • Visual predators using raptorial appendages to capture small prey
  • Little is known about the ecology of this species


  • Bradford-Grieve, J. M., E. L. Markhaseva, et al. (1999). Copepoda. South Atlantic Zooplankton. D. Boltovskoy. Leiden, The Netherlands, Backhuys Publishers. 1: 869-1098.
  • Dahl, M. (1912). Die Copepoden der Plankton-Expedition. I. Die Corycaeinen. Mit Berucksichtigung aller bekannten Arten bearb. (Ergebnisse der Plankton-Exp. Bd II. G. f. 1.).@@Pages: (iv + 136) @ 
  • Tanaka, O. (1957[1959]). On copepoda of the family Corycaeidae in Japanese waters 1957. Contx Dep Fish Kyushu Univ 3