Open Access Open Access  Restricted Access Subscription or Fee Access


Archeterokrohnia docrickettsae (Chaetognatha: Phragmophora: Heterokrohniidae), a new species of deep-sea arrow worm from the Gulf of California



A new species of deep-sea chaetognath, Archeterokrohnia docrickettsae n. sp. is described from a single specimen captured by the ROV Doc Ricketts ~2 m above the sea floor at 3245 m depth in the Pescadero Basin of the Gulf of California, Mexico. This is the first record of a living specimen of Archeterokrohnia and the second known occurrence of Archeterokrohnia in the Pacific Ocean. In life, the head and trunk sections were orange, while the tail section was translucent, a unique colour pattern not before seen in chaetognaths. Observations of its swimming behaviour in situ are given. Comparisons are made with the three other species of Archeterokrohnia. At 28.5 mm in length, this is the largest known species of the genus. An artificial key to the four species of Archeterokrohnia is presented.



Gulf of California, chaetognath, deep sea, zooplankton

Full Text:

PDF/A (7.20 MB)


Bieri, R. (1991) Systematics of the Chaetognatha. In: Bone, Q., Kapp, H. & Pierrot-Bults, A.C. (Eds.), The Biology of Chaetognaths. Oxford University Press, Oxford, pp. 122–136.

Bieri, R., Terazaki, M., Thuesen, E.V. & Nemoto, T. (1987) The colour pattern of Spadella angulata (Chaetognatha: Spadellidae) with a note on its northern range extension. Bulletin of Plankton Society of Japan, 34, 83–84.

Casanova, J.-P. (1986a) Archeterokrohnia rubra, n. gen., n. sp., nouveau Chaetognathe abyssal de l'Atlantique nord-africain: description et position systématique, hypothèse phylogénétique. Bulletin du Muséum National d'Histoire Naturelle, Paris, sér.4, 8, 185–194.

Casanova, J.-P. (1986b) Découverte en Méditerranée d'un chaetognathe nouveau de genre archaïque profond Archeterokrohnia: description et signification biogéographique. Rapport et Procés-verbaux Réunions de la Commission internationale pour l'Exploration scientifique de la Mer Méditerranée, 30, 196.

Casanova, J.-P. (1991) Chaetognaths from the Alvin dives on the Seamount Volcano 7 (east tropical Pacific). Journal of Plankton Research, 13, 539–548.

Casanova, J.-P. & Duvert, M. (2002) Comparative studies and evolution of muscles in chaetognaths. Marine Biology, 141, 925–938.

Haddock, S.H.D. (2004) A golden age of gelata: past and future research on planktonic ctenophores and cnidarians. Hydrobiologia, 530/531, 549–556.

Haddock, S.H.D. & Case, J.F. (1994) A bioluminescent chaetognath. Nature, 367, 225–226.

Hagen, W. & Kapp, H. (1986) Heterokrohnia longicaudata, a new species of Chaetognatha from Antarctic waters. Polar Biology, 5, 181–183.

Kapp, H. (1991) Archeterokrohnia Casanova, 1986, a junior synonym of Heterokrohnia Ritter-Záhony, 1911 (Chaetognatha), with a review of the species of Heterokrohnia. Helgolander Meeresuntersuchungen, 45, 237–252.

Steinbeck, J. (1945) Cannery Row. Viking Press, New York, 208 pp.

Steinbeck, J. & Ricketts, E.F. (1941) Sea of Cortez: A leisurely journal of travel and research. Viking Press, New York, 598 pp.

Terazaki, M., Marumo, R. & Fujita, Y. (1977) Pigments of meso- and bathypelagic chaetognaths. Marine Biology, 41, 119–125.

Thuesen, E.V. & Childress, J.J. (1993) Enzymatic activities and metabolic rates of pelagic chaetognaths: lack of depth-related declines. Limnology and Oceanography, 38, 935–948.

Thuesen, E.V., Goetz, F.E. & Haddock, S.H.D. (2010) Bioluminescent organs of two deep-sea arrow worms, Eukrohnia fowleri and Caecosagitta macrocephala, with further observations on bioluminescence in chaetognaths. Biological Bulletin, 219, 100–111.

Tokioka, T. & Bieri, R. (1966) The colour pattern of Spadella angulata Tokioka. Publications of the Seto Marine Biological Laboratory, 14, 323–326.


  • There are currently no refbacks.

ISSN 1175-5326 (Print Edition) & ISSN 1175-5334 (Online Edition)
Published by Magnolia Press, Auckland, New Zealand
A founding journal of Biotaxa