Corydendrium parasiticum (Linnaeus, 1767)

Castro Mendonça, Luana M., Parisotto Guimarães, Carmen R. & Haddad, Maria A., 2022, Taxonomy and diversity of hydroids (Cnidaria: Hydrozoa) of Sergipe, Northeast Brazil, Zoologia (e 21032) 39, pp. 1-65 : 14-17

Corydendrium parasiticum (Linnaeus, 1767)

Fig. 7A–B

Synonyms available from: Schuchert (2004).

Sertularia parasitica Linnaeus, 1767: 1315 .

Corydendrium parasiticum – Migotto, 1996: 11, fig. 2e.

Description: Colonies erect, up to 6 cm high, arising from a creeping hydrorhiza. Stem polysiphonic, branched, 0.31–0.54 mm wide. Secondary branches connected to the main stem for almost its entire length, gradually curving outward and becoming free in the distal portion. Perisarc smooth, partially covered by silt, moderately thick in almost all the length of the stem, becoming thinner in the distal portion. Hydranths fusiform and elongated, 0.73–1.39 mm high, 0.23–0.33 mm wide. Hypostome long, dome-shaped, with 25–38 filiform tentacles spread across its body. Gonophores triangular-shaped, 0.22–0.54 × 0.09–0.19 mm, inserted inside the final portion of the stem, just below the hydranth.

Material examined: VB – abundant colonies, one of them with gonophores, from the dry and rainy seasons; SE – few infertile colonies from the dry season. CZUFS CNI-00046; CNI-00092.

Stations: VB - C1P12, C1P34, C1P56, C2P12, C2P34, C2P56, C3P34, C3P56; SE - C3P34, C3P56.

Distribution: Brazil – Pernambuco ( Calder and Maÿal 1998), São Paulo ( Migotto 1996, Silveira and Morandini 2011, Fernandez et al. 2014, 2015), and Paraná ( Bumbeer and Rocha 2012). World distribution – probably circumglobal in tropical and subtropical regions ( Schuchert 2004).

Remarks: Colonizing the plates, Ostreidae , Polychaeta tubes, Ascidiacea, and Pennaria disticha .

Turritopsis nutricula McCrady, 1857 Fig. 7C–D

Corydendrium nutricula (McCrady, 1857) (unaccepted combination).

Modeeria multitentaculata Fewkes, 1881 (synonym).

Description: Colonies stolonal or erect, irregularly branched, up to 1.5 mm high. Stem monosiphonic, 0.07–0.13 mm wide. Perisarc moderately thick slightly striated at the base of the hydranths. Hydranths fusiform, 0.32–0.78 mm high, 0.09–0.12 mm wide, with a conical and elongated hypostome. Filiform tentacles (7–12) irregularly spread over the half distal portion of the hydranths. Tentacles at the base of the hydranths are shorter than those at the medial and distal portions. A single individual was found with three medusa buds, measuring 0.24–0.3 × 0.12–0.22 mm, inserted at the distal portion in short pedicels. Nematocysts: eurytele undischarged large (one visualized 55.2 × 20.7 µm) and small (18.6–23 × 7.8–9.3 µm), stenoteles discharged (8.1–11.1 × 7.3–9.2 µm). Euryteles were found only in the coenosarc, while stenoteles were present in the hydrorhiza, coenosarc, and hydranth.

Material examined: PCS – abundant infertile colonies from the dry and rainy seasons; VB – abundant infertile colonies from the dry and rainy seasons; SE – one fertile colony from the dry season. CZUFS CNI-00087; CNI-00088; CNI-00095; CNI-00096; CNI-00097; CNI-00098.

Stations: PCS – 1, 4, 10, 11, 12, 16, 17; VB – C1P12, C1P34, C1P56, C2P12, C2P34, C2P56, C3P34; SE – C1P12.

Bottom: gravel, sand, and mud.

Distribution: Brazil – Pernambuco ( Calder and Maÿal 1998), Sergipe (medusa, Araújo 2006), Bahia (Kelmo and Santa- -Isabel 1998), Espirito Santo ( Grohmann et al. 1997), São Paulo ( Migotto 1996, Marques et al. 2001, Oliveira et al. 2006, Oliveira and Marques 2011, Silveira and Morandini 2011, Fernandez et al. 2014, 2015), and Paraná ( Bumbeer and Rocha 2012, Nagata et al. 2014). World distribution – widely distributed in Western Atlantic (Calder 2019).

Taxonomic remarks: For a long time, T. nutricula was considered a cosmopolitan species, and all other species of the genus as its synonyms ( Martell et al. 2016). However, morphological ( Schuchert 2004) and molecular studies ( Miglietta et al. 2007, Miglietta 2016, Li et al. 2018) separate the Turritopsis species, in exclusive lineages for the Atlantic ( T. nutricula ), Mediterranean ( T. dohrnii (Weismann, 1883)) and Pacific ( T. rubra (Farquhar, 1895)) . Due to all these taxonomic paths, the synonyms mentioned by Calder (1988) are no longer adequate. A new revision of the genus is required to elucidate the occurrence and distribution of the different species and their synonyms.

Remarks: The PCS material was colonizing Anthozoa ( Carijoa sp. ), Bryozoa, and the hydroid Thyroscyphus ramosus . Estuarine material was colonizing the plates, Ostreidae , Bryozoa, Ascidiacea, and the hydroids Corydendrium parasiticum , Diphasia digitalis , Eudendrium merulum , and Pennaria disticha .

Superorder Leptothecata Cornelius, 1992 Infraorder Campanulariida Bouillon, 1984 sensu novum Campanulariidae Johnston, 1836 Campanularia sp. 1 Fig. 8A

Description: Colony stolonal, polyps up to 698 µm high, arising from a creeping hydrorhiza. Pedicels with a moderately thick perisarc, one large and square-shaped annulus with a rounded corner at the distal end. Hydrothecae cylindrical, 259–347 µm high, 146–258 µm wide, walls with perisarc moderately thick. Diaphragm thin, apparently straight near the hydrothecal base. Margin with 10 rounded cusps, with U-shaped embayments between them.

Material examined: PCS – one infertile colony from the rainy season.

Station: 11.

Bottom: sand.

Taxonomic remarks: Four species of Campanularia are recorded to the Brazilian coast: C. agas Cornelius, 1982 , C. hesperia Torrey, 1904 , C. hincksii Alder, 1856 , and C. lennoxensis Jäderholm, 1903 ( Oliveira et al. 2016), however, the PCS specimens have a completely waved pedicel with a large annulus at the distal end, and that annulus looks square-shape in profile with rounded corners, and this characteristic was not seen in any of the species recorded to Brazil. The PCS specimens resemble Campanularia volubilis (Linnaeus, 1758) as described by Cornelius (1995b, p. 232) and also the illustrations for this species made by Nutting (1901, p. 345, fig. 26), however, C. volubilis is a boreal-Arctic species and would not occur in Sergipe. Nevertheless, the absence of gonothecae, nematocysts and hydranths did not allow a better characterization of the PCS specimens.

Remarks: Colonizing algae, and the hydroid Sertularelloides cylindritheca .

Figures

Figure 7. (A-B) Corydendrium parasiticum: (A) general view of a colony; (B) detail of a stem showing gonophores (red arrows); (C-D) Turritopsis nutricula: (C) general view of a colony; (D) detail of a polyp showing gonophores (red arrows).

Figure 8. (A) Campanularia sp. 1: general view of a polyp; (B) Clytia hemisphaerica: general view of polyps and two gonothecae (red arrows); (C) Clytia elsaeoswaldae: general view of two polyps and a gonotheca (red arrows); (D, G) Campanularia sp. 2: (D) general view of a polyp; (G) detail of the hydrotheca; (E-F) Clytia gracilis: (E) general view of two polyps and two gonothecae (red arrows); (F) general view of a polyp.