Campanularia lennoxensis Jäderholm, 1903

Galea, Horia R., Häussermann, Verena & Försterra, Günter, 2009, New additions to the hydroids (Cnidaria: Hydrozoa) from the fjords region of southern Chile, Zootaxa 2019, pp. 1-28 : 16-17

Campanularia lennoxensis Jäderholm, 1903

(fig. 4A–F, table 5)

Campanularia lennoxensis Jäderholm, 1903: 268 , pl. 1 figs 4–5.

? Campanularia lennoxensis – Nutting, 1915: 52, pl. 10 figs 5–6.

not Orthopyxis lennoxensis – Vannucci Mendes, 1946: 544, pl. 1 figs 3–5 [= Campanularia sargassicola ( Nutting, 1915) ].

Campanularia subantarctica Millard, 1971: 403 , fig. 5. – Stepanjants, 1979: 32, pl. 5 figs 4–5.

Campanularia (Orthopyxis) everta – Blanco, 1976: 36, pl. 3 fig. 4 (not Campanularia everta Clark, 1876 ).

? Campanularia tincta var. eurycalyx Hartlaub, 1905: 558 , figs G1–H1 (not Campanularia tincta Hincks, 1861 ).

Eucopella crenata – Hartlaub, 1905: 568, fig. Q1 [not Orthopyxis crenata ( Hartlaub, 1901b) ].

Material examined. Stn. 6 – 21.02.2008, 12 m, A470 ( MHNG INVE 62816): a minute, sterile colony composed of several hydrothecae, epizoic on Amphisbetia operculata ( Linnaeus, 1758) ; A472 ( MHNG INVE 62817): small, sterile colonies, epizoic on A. operculata ; A475 ( MHNG INVE 62818): fertile (male) colonies epizoic on A. operculata . Stn. 7 – 22.02.2008, 15.6 m, A128: a sterile colony, epizoic on Sertularella sanmatiasensis El Beshbeeshy, 1991 . Stn. 8 – 23.02.2008, 26 m, A580 ( MHNG INVE 62820): sterile colonies, epizoic on Symplectoscyphus milneanus (d’Orbigny, 1846) . Stn. 9 – 24.02.2008, 20 m, A494 ( MHNG INVE 62821): numerous small, fertile (female) colonies, epizoic on A. operculata ; A495 ( MHNG INVE 62822): small colonies, some with gonothecae (male), epizoic on both Symplectoscyphus leloupi El Beshbeeshy, 1991 and A. operculata ; A515 ( MHNG INVE 62819): several colonies with male gonothecae, epizoic on A. operculata .

Type locality. Lennox Island (ca. 55°17´S, 66°57´W), southern Chile.

Description. Colonies stolonal, with creeping hydrorhiza from which arise quite short, unbranched, irregularly spirally-twisted pedicels. A hydrotheca at top of pedicel, with subhydrothecal below hydrotheca. Hydrotheca bell-shaped, about twice as long as wide; sides nearly parallel, with quite thick perisarc; an annular thickening near base delimiting a roughly spherical basal chamber; rim with 9–13 long, triangular cusps with bluntly rounded tips, separated by deep embayments; in cross section, wall of hydrotheca below aperture folded alternately inwardly (at cusps) and outwardly (at embayments); rim occasionally renovated up to 5 times (not shown). Colonies monoecious. Gonothecae of both sexes borne on stolon, oval-elongated, almost radially symmetrical in transverse section, broadest in middle, tapering gradually above into short, smooth pedicel; distal end of gonotheca truncated, with small, circular aperture mounted on low collar; perisarc thick, slightly undulated. Female gonothecae comparatively longer than male. The latter, with spermatocytes arranged in four longitudinal bands; female ones containing ca. 12 planulae filling lower 2/3rd of gonotheca, but possibly up to 18–20 of them can be contained inside. No additional observations on the fine structure of the gonophore could be made on preserved material.

Remarks. Millard (1971) described Campanularia subantarctica based on fertile material from Marion Island (46°53´S, 37°52´E). She found it similar with Jäderholm’s (1903) C. lennoxensis , except for the perisarc of the hydro- and gonothecae, which was thin in her specimens and strongly thickened in his material. Variation in perisarc thickening is very common in a number of campanulariids, e.g. Orthopyxis crenata ( Hartlaub, 1901b) , O. integra ( MacGillivray, 1842) . Therefore, we see no reason to create a new species on the account of the degree of thickening of the perisarc, and include Millard’s species in the synonymy of C. lennoxensis .

The gonothecae in Jäderholm’s (1903) material reached about 1000 µm in length and 500 µm in maximal width and, compared with the present specimens, were presumably male. In contrast, the gonothecae described by Millard (1971) are comparatively longer, and are here presumed to be female (see table 5).

Present study Jäderholm (1903) Blanco (1976), as Campanularia Millard (1971) , as (Orthopyxis) everta Clark, 1876 Campanularia subantarctica

Hydrorhiza

Campanularia tincta var. eurycalyx described by Hartlaub (1905) from the Falkland Islands has a very similar trophosome and may belong to the present species. Additionally, the specimens from Puerto Pantalon, Chile, assigned to Eucopella crenata are clearly conspecific with C. lennoxensis , and are easily recognizable due to their 10–12 triangular hydrothecal cusps.

The study of living material of this species would be necessary to ascertain the true nature of its gonophore, and whether this species belongs either to Campanularia Lamarck, 1816 or Orthopyxis L. Agassiz, 1862 .

World distribution. A subantarctic species with a few scattered records: Marion Island ( Millard 1971), off the Pacific side of the Magellan Strait ( Blanco 1976), Falkland Islands ( Hartlaub 1905, as C. tincta var. eurycalyx ).

Records from Chile. Lennox Island ( Jäderholm 1903), West of Puerto Pantalon ( Hartlaub 1905, as Eucopella crenata ), South of Chiloé Island (present study).