Campanularia, Lamarck, 1816

Soto, Joan J. & Peña, Álvaro L., 2019, Benthic hydroids (Cnidaria, Hydrozoa) from the Weddell Sea (Antarctica), Zootaxa 4570 (1), pp. 1-78 : 28

Campanularia sp.

( Fig. 7 i–j)

Material examined. ANT XV/3: 48-27, few hydrothecae, up to 6 mm high, on Sy. anae ; 48-36, several hydrothecae, up to 5 mm high, on O. terranovae ; 48-220, several hydrothecae, up to 6 mm high, on H. interpolatum , Sc. nana , St. glomulosa and Sy. exochus , with developing gonothecae; 48-222, few hydrothecae, up to 6 mm high, on Sc. nana ; 48-223, few hydrothecae, up to 6 mm high, on Sc. nana ; ANT XVII/3: 111-6, few hydrothecae, up to 6 mm high, on B. subrufa ; ANT XXI/2: PS65/39, few hydrothecae, up to 5 mm high, on Sc. nana and Sy. glacialis ; PS65/174, few hydrothecae, up to 4 mm high, on O. erratum ; PS65/175, few hydrothecae, up to 5 mm high, on Sy. glacialis ; PS65/248, few hydrothecae, up to 6 mm high, on H. incertus and St. nonscripta ; PS65/ 274, few hydrothecae, up to 5 mm high, on St. nonscripta ; PS65/278, few hydrothecae, up to 5 mm high, on H. secundum ; PS65/280, some hydrothecae, up to 7 mm high, on Sy. glacialis ; PS65/281, few hydrothecae, up to 7 mm high, on O. terranovae .

Remarks. Material studied here is probably conspecific with Campanularia sp. reported from several localities in the Southern Ocean by Peña Cantero (2006, 2013, 2014a, 2017), Peña Cantero & Gili (2006) and Peña Cantero et al. (2004, 2013). The material agrees in the shape and size of hydrothecae (850–950 µm in length and 350–450 µm in diameter at aperture), as well as in nematocyst size. The species, however, has never been found with gonothecae (see Peña Cantero 2017). Material examined from XV/3 48–220 has developing gonothecae ( Fig. 7j ), but unfortunately they cannot be completely characterized given its incomplete maturation. In contradistinction to the young specimens of C. hicksoni , whose hydrothecae concur in shape and size to that of Campanularia sp., the range of the nematocyst size obtained for the latter is narrower, and the largest nematocysts do not reach more than 10.5 µm in length (see below). For these reasons, we prefer keeping both species as separated entities until new evidence becomes available.

Cnidome composed of large microbasic mastigophores [range 9.0–10.5 x 1.5–2.0 µm, mean 9.8±0.5 x 1.7±0.2 µm (n=56)] and small microbasic mastigohpores [range 6.5–7.5 x 1.5–2.0 µm, mean 7.0±0.4 x 1.5±0.1 µm (n=22)].

Ecology and distribution. Previously known from 15 (Peña Cantero et al. 2013) to 728 m ( Peña Cantero 2014a); present material comes from depths between 68 to 291 m. Hitherto, it has been reported from the Weddell Sea (Peña Cantero et al. 2004) and off South Shetland Islands (Peña Cantero, 2006, 2013) in west Antarctica; from Queen Mary Coast ( Peña Cantero 2014a) and the Ross Sea (Peña Cantero 2017, Peña Cantero et al. 2013) in East Antarctica; and from Bouvet Island ( Peña Cantero and Gili 2006). Thus, the species can be regarded as Circum- Antarctic.

Figures

FIGURE 7. a Lafoeina longitheca: hydrotheca. b–c Stegella lobata: b stem showing hydrothecal arrangement; c gonotheca. d Phialella belgicae: hydrotheca. e–h Campanularia hicksoni: e general view of the colony; f hydrotheca; g pioneer polyp showing planula attachment; h gonotheca. i–j Campanularia sp.: i hydrotheca; j developing gonotheca. k–m Billardia subrufa: k general view of a colony growing on Oswaldella erratum; l stem showing hydrothecal arrangement; m gonothecae.