The variation of Halocordyle disticha (Cnidaria, Athecata) from the Brazilian coast: an environmental indicator species?

Abstract

The rediscovery of Halocardylefragilis Vannucci, of which the type material is lost, led us to consider it a variety of Halocardyle disticha (Goldfuss) that occurs in calm waters on soft bottoms. The typical H. disticha is open feather-shaped, with branching in one plane, while H. fragilis is bushy, much larger, with branching in many planes. The different habit of H. disticha is probably due to environmental conditions. The bushy and pinnate forms are considered extremes of a range of morphological variation.

Synchronous Mass Release of Mature Medusae from the Hydroid Halocordyle disticha (Hydrozoa, Halocordylidae) and Experimental Induction of Different Timing by Light Changes

“…This hydrozoan is one of a few Anthomedusae that have an upright stem with a regular pattern of branching; other arrangements have been described, though such as bushy to pinnate forms that have been considered morphological variations due to different environmental conditions (Silveira and Migotto, 1991). In any colony form, the hydranths have an aboral whorl of filiform tentacles and an oral set of short, capitate tentacles amid which medusa buds are produced.…”

Hydroids (Cnidaria, Hydrozoa) collected on the inner continental shelf of the state of Rio de Janeiro, Brazil, during the Oceanographic Operations GEOCOSTA RIO I and II

“…11,no. 2 Noronha Archipelago (Eston et al 1986, Pires et al 1992) and near Tamandaré (Calder & Maÿal 1998), as well as from Bahia (Kelmo & Santa-Isabel 1998, Grohmann et al 2003, Espírito Santo (Vannucci 1951b, Souza 1987, Grohmann et al 1997, Rio de Janeiro (Vannucci 1950(Vannucci , 1951a) São Paulo (Vannucci 1954, Migotto & Silveira 1987, Silveira & Migotto 1991, Migotto 1996, Rosso & Marques 1997, Marques & Migotto 2004, Paraná (Vannucci 1954, Migotto 1996 and Santa Catarina (Silveira & Migotto 1991). Bimeria vestita is known from Ceará (Shimabukuro et al 2006), Bahia (Kelmo & Santa-Isabel 1998), Espírito Santo (Grohmann et al 1997), and São Paulo (Migotto 1996, Rosso & Marques 1997, Marques & Migotto 2004).…”

Fauna de hidrozoários atecados (Hydrozoa, Anthoathecata) da costa do Estado do Ceará, Brasil

“…A espécie apresenta alta plasticidade fenotípica (Silveira & Migotto 1991) como resposta a variações no hidrodinamismo. A forma encontrada na maioria dos locais no litoral cearense é a penada, presumida como associada a locais com correntes unidirecionais.…”