Pseudosagitta maxima (Conant, 1896)
The Arctic's large, bathypelagic arrow worm
Size
- body up to 9 cm
Color & Characteristics
- Body flacid & translucent, eyes with small distinct black spot
- 2 pairs of touching fins: anteriro pair elongated, reaching anterior ganglia; posterior pair rounded, both with incomplete rays
- Head broad, tail 19-25% of length
- Each side of head with 5-11 unserrated hooks, 4-6 anterior and 19-25 posterior teeth
- Collarette absent
- Semininal vesicles conical, separated from but clsoe to posterior fins, well separated from tail fin
- Ovaries thin and of medim length, stretching to ganglion, with small eggs
Habitat
- Cosmopolitan
- Oceanic, primarily bathypelagic (1000-3000m), or deep mesopelagic, even deeper in tropics
Feeding
- An ambush predator, detecting motion with numerous tiny hairs along body
- Pey seized with hooks during a rapid lunge, ratched whole down throat with aid of teeth
- Prey size largely determined by head width
- Diet poorly described - likely composed of copepods, ostracods, and lower numbers of larvaceans and other chaetognaths
Life cycle
- Protandrous (releasing sperm first, then producing eggs)
- Fertilized eggs released as stickly masses
- Generation time unknown, likely 2+ years in the Arctic
Page Author: Russ Hopcroft
Created: November 15, 2011
