Lafoea dumosa Fleming, 1820

Phylum:Cnidaria Hatschek, 1888
Class:Hydrozoa Owen, 1843
Order:Leptothecata
Family:Lafoeidae
Genus:Lafoea

Colonies erect, 1–2 cm high, polysiphonic, thinning to monosiphonic,

component tubes parallel, each bearing hydrothecae at irregular intervals, arising from all sides of branches. Hydrothecae tubular, straight, about 0.5 mm deep, opening diameter 0.18 mm, cylindrical, tapering below into distinct pedicel, pedicel corrugated; rim of opening slightly flared; no diaphragm or operculum.

Gonothecae absent (see Millard 1975 or Cornelius 1995a).

Lafoea dumosa is here recorded in Indonesian waters for the first time. This cosmopolitan and extraordinarily variable species has an extensive and complicated synonymy (see Cornelius 1975b, Rees & Vervoort 1987, Schuchert 2001). Contemporary authors mostly do not distinguish anymore between forms having hydrothecae on stalks or sessile ones. However, Schuchert (2001) noted that most colonies with sessile hydrothecae also have significantly smaller isorhiza capsules, suggesting nevertheless the presence of two species. The present material from Indonesia (Fig. 16) had without exception hydrothecae with distinct stalks and the larger nematocyst capsule measured around 25 μm in length, thus conforming with the common Atlantic form. Distribution Cosmopolitan, mostly below 100 m

Literature

  • Schuchert, P. Hydroids (Cnidaria, Hydrozoa) of the Danish expedition to the Kei Islands. Steenstrupia 27 (2): 137256. Copenhagen, Denmark, May 2003 (for 2001). ISSN 0375-2909.

Author: Zakharov Denis V. / 13.02.2017
Last edit: Zakharov Denis V. / 13.02.2017

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