Archeterokrohnia

Archeterokrohnia is a genus of chaetognaths in the family Heterokrohniidae.The total body length excluding tail fin 28.5; the tail section is 55.2% of the tail fin; head blunt when hooded, triangular after preservation, head with 3.5 mm. Furthermore, the eyes are absent, the trunk section is orange throughout in life, and the organism exists around 3200 m below sea level.[2]

Archeterokrohnia
Archeterokrohnia docrickettsae holotype. A, lateral view; B, dorsal view; C, dorsal view, after 4 months preservation. Scale bar: 2 mm.
Scientific classification
Kingdom:	Animalia
Phylum:	Chaetognatha
Class:	Sagittoidea
Order:	Phragmophora
Family:	Heterokrohniidae
Genus:	Archeterokrohnia Casanova, 1986[1]

Species

• Archeterokrohnia docrickettsae Thuesen & Haddock, 2013[3]
• Archeterokrohnia longicaudata (Hagen & Kapp, 1986)[4]
• Archeterokrohnia palpifera Casanova, 1986[1]
• Archeterokrohnia rubra Casanova, 1986[1]

References

1. Casanova, J. (1986). 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, (4)8(A), 185–194.
2. Thuesen, Erik V., and Steven H.d. Haddock. “Archeterokrohnia Docrickettsae (Chaetognatha: Phragmophora: Heterokrohniidae), a New Species of Deep-Sea Arrow Worm from the Gulf of California.” Zootaxa, 2013 Magnolia Press, www.mapress.com/j/zt/article/view/zootaxa.3717.3.2/32220.
3. Thuesen, E. V. & Haddock, S. H. (2013). Archeterokrohnia docrickettsae (Chaetognatha: Phragmophora: Heterokrohniidae), a new species of deep-sea arrow worm from the Gulf of California. Zootaxa, 3717(3), 320–328.
4. Hagen, W. & Kapp, H. (1986). Heterokrohnia longicaudata, a new species of Chaetognatha from Antarctic waters. Polar Biology, 5, 181–183.

[[Thuesen, Erik V., and Steven H.d. Haddock. “Archeterokrohnia Docrickettsae (Chaetognatha: Phragmophora: Heterokrohniidae), a New Species of Deep-Sea Arrow Worm from the Gulf of California.” Zootaxa, 2013 Magnolia Press, www.mapress.com/j/zt/article/view/zootaxa.3717.3.2/32220.]]