Taxonomic revision and systematic notes on some Halecium species (Cnidaria, Hydrozoa) Author Schuchert, Peter text Journal of Natural History 2005 2005-02-28 39 8 607 639 http://dx.doi.org/10.1080/00222930400001319 journal article 10.1080/00222930400001319 1464-5262 4668977 Halecium petrosum Stechow, 1919 ( Figure 8 ) Halecium robustum : Motz-Kossowska 1911 , p 346 , Figure 14 ; Neppi 1921 , p 13, Figures 4 , 5 . [Not Halecium robustum Pieper 1884 , p 166 .] Halecium petrosum Stechow 1919 , p 36 , new name; Coma et al. 1992 , p 162, Figure 1A ; Peña Cantero and García Carrascosa 2002 , p 69, Figure 14 a–c. Figure 8. Halecium petrosum Stechow, 1919 ; after material from Banyuls-sur-Mer. (A) Colony silhouette (scale bar: 5 mm); (B) two internodes (scale bar 0.2 mm); (C) branching point (same scale bar as B); (D) hydrophore, primary and secondary hydrothecae (scale bar: 0.1 mm); (E) hydrotheca with straight walls (same scale bar as D); (F) female gonotheca in side view (same scale bar as B); (G) hydrotheca of female gonotheca in anterior view (anterior side in F is directed towards left) (same scale bar as D); (H) part of male colony, sperm masses stippled, note that this sample shows signs of multiple re-growth and regeneration, its identity is not entirely secure (scale bar: 0.2 mm). Material examined MHNG INVE 26665 , Anse de Troc , Banyuls-sur-Mer Pyrénées Orientales , France , 2 m , coll. P. Schuchert , 23 June 1997 , fertile female . MHNG INVE 29763 , Spain , Mallorca , Cala Murada , coll. P. Schuchert , 23 August 2000 , 0.5 m , on rock and red algae, shows signs of multiple re-growth and regenerations, identification not entirely secure . Description Colonies erect, branched, shoots 5–15 mm , monosiphonic, composed of main axis and shorter side-branches. Erect parts segmented by alternately oblique nodes; nodes distinct, internodes about 0.5–0.6 mm long, diameter 80–90 mm . Perisarc smooth. Side-branches originate from hydrophores. Hydrotheca near segment end, on very short hydrophore; hydrotheca does not reach beyond level of node. Primary hydrotheca with straight or slightly curved walls, basal diameter 0.10–0.12 mm , depth 20–30 mm , desmocytes present. Hydrophore without pseudodiaphragm. Secondary hydrotheca on corrugated hydrophore of variable length, several times longer than primary hydrophore. Gonothecae on main stem. Female gonotheca 0.6–0.7 mm long and about 0.5 mm broad, main body ovoid, bilaterally symmetric through a lateral hydrotheca that overtops gonotheca body, with crease-line running from hydrotheca along gonotheca body. Male gonothecae without hydrotheca, club-shaped, slightly curved or not, length 0.5–0.55 mm . Additional information Stems may reach 3 cm in height. Female gonotheca with two hydranths ( Motz-Kossowska 1911 ). Biology Depth range 1–200 m , grows on a variety of solid substrata. Fertile colonies observed from June to October ( Peña Cantero and García Carrascosa 2002 ). Ecological aspects were investigated by Coma et al. (1992) . Distribution Mediterranean. Type localities: Cap Béar and Cap Abeille near Banyuls-sur-Mer , France , Mediterranean . Remarks Motz-Kossowska (1911) identified abundant material from Banyuls as Halecium robustum Pieper, 1884 . The latter name was recognized by Bedot (1912 , p 14) as a synonym of H. lankesterii (see also Hamond 1957 for more invalid homonyms of Halecium robustum ). Because Motz-Kossowska’s material had female gonothecae that differed from typical H. lankesterii , Stechow (1919) attributed it to a new species with the name Halecium petrosum (compare Figures 8F and 7E ). Also the trophosomes of Halecium lankesterii and H. petrosum are quite distinct (compare Figures 7B and 8B , and remarks under H. lankesterii ).