Halecium erratum Galea, Försterra, Häussermann & Schories, 2014

Galea, Horia R., Schories, Dirk, Försterra, Günter & Häussermann, Verena, 2014, New species and new records of hydroids (Cnidaria: Hydrozoa) from Chile, Zootaxa 3852 (1), pp. 1-50 : 11-12

Halecium erratum Galea, Försterra, Häussermann & Schories , sp. nov.

( Table 3 )

Halecium fraseri ― Leloup, 1974: 11, Fig. 8 .―Galea et al., 2007: 57, Fig. 2 C–K.

not Halecium fraseri Ralph, 1958: 338 (= new name for H. flexile ― Fraser, 1914: 165, pl. 20 Fig. 71; 1937: 104, pl. 21 Fig. 111; 1944: 192, pl. 35 Fig. 169; 1946: 73, 264; 1948: 222; not H. flexile Allman, 1888 ).

Material examined. HF4, Fjord Piti Palena, Raul Marin, lat. -43.77517, -72.87843, 09.iii.2007, 15– 20 m, sample 1461: a female colony (holotype: MHNG-INVE-54634); sample 1465: a male colony (paratype: MHNG-INVE- 86144). Caleta La Arena, Caleta Yerbas Buenas, lat. -41.67263, long. -72.65650, 11.vii.2010, 30 m, sample 04: a 15 cm high, female colony (MHNG-INVE-79659); 12.vii.2010, 40– 47 m, sample 06: two sterile colonies, 18 and 20 cm high, respectively (MHNG-INVE-79658); 07.x.2011, 40 m, sample 01: a 14 cm high, sterile colony (MHNG-INVE-86258).

Remarks. Since the first specimens were described by some of us (Galea et al. 2007) under the specific name H. fraseri Ralph, 1958 , new material was gathered and additional literature sources became available to us. Ralph (1958) assigned the new name H. fraseri to a hydroid apparently misidentified as H. flexile in a series of papers by Fraser (1914, 1937, 1944, 1946, 1948), its area of occurrence being mainly the Pacific coast of North America ( Fraser 1937, 1948), with an additional record from a locality in the northwestern Atlantic ( Fraser 1944).

From the descriptions available for the North American species, it is realized that it exhibits some features that are not met with in our Chilean material, and these are listed in Table 3 . Consequently, our material is considered as belonging to an undescribed species, and the new name H. erratum is proposed for it.

Etymology. The specific name borrows the Latin noun erratum , with reference to an earlier, erroneous assignment of this species to another taxon.

Distribution in Chile. Fjord Piti Palena (Galea et al. 2007) and South of Puerto Montt (present record).

World records. Not known from elsewhere.

Figures

FIGURE 8. A ‒ D: Symplectoscyphus unilateralis (Lamouroux, 1824) — stem fragment (A); hydrotheca (B); gonotheca in frontal (C) and lateral (D) views. E ‒ H: Symplectoscyphus sp. — colony fragment (E); hydrotheca in lateral (F) and apical (G) views; gonotheca (H). I, J: Staurotheca jaederholmi Stechow, 1920 — colony fragment (I); gonothecae (J). K ‒ M: Parascyphus simplex (Lamouroux, 1816) — stem fragment (K); hydrotheca (L) and detail of aperture (M). N, O: Halopteris plumosa Galea & Schories, 2012 a—female (N) and male (O) gonothecae. Scale bars: 200 µm (A, B, F, G), 300 µm (C, D, L ‒ O), 500 µm (H, K), 1 mm (E, I, J).

FIGURE 2. A, B: Halecium flexile Allman, 1888 — portion of stem (A) compared with H. balei Fraser, 1911 (C); detail of hydrophore and renovated hydrotheca (B), and comparison with H. balei (D). E, F: Halecium humeriformis sp. nov. — stem fragments (E); hydrophore and renovated hydrotheca (F). G, H: Halecium maximum sp. nov. — stem fragments (G); hydrophore and renovated hydrotheca (H). I ‒ L: Halecium modestum sp. nov. — stem fragments (I ‒ K); hydrophore with hydrotheca (L). M, N: Halecium platythecum sp. nov. — stem fragment (M); hydrophore and renovated hydrotheca (N). Scale bars: 300 µm (B, D, F, H, L, N) and 1 mm (A, C, E, G, I ‒ K, M).

Tables

TABLE 3. Comparison of H. erratum sp. nov. with Halecium fraseri Ralph, 1958.

	Present study, as H. erratum sp. nov.	Fraser (1914, 1937, 1944), as H. flexile Allman, 1888
Colony	Generally tall, up to 20 cm high, fan shaped, coplanar	Of moderate height, judging from Fraser’s (1914) Fig. 111A; regularly pinnate
Stem	Polysiphonic, up to. 1.5 mm wide at base, tapering gradually towards tip	Coarse, strongly polysiphonic, unbranched
Internodes	Long, collinear; primary hydrophores surpassing for a short distance the distal node.	Rather short, slightly geniculate; primary hydrophores and their hydrotheca may reach middle part of internodes (Fraser 1937, Pl. 21 Fig. 111C)
Cladia	Well developed, polysiphonic, becoming monosiphonic distally, normally branched (up to 3rd order), giving rise to multi-pinnate structures like the stem (Galea et al. 2009, Fig. 2C)	Short, polysiphonic basally, usually unbranched
Hydrophore	Well developed, with an unmistakable pseudodiaphragm running obliquely from adaxial to abaxial side (Galea et al. 2009, Fig. 2D, F)	Well developed, apparently devoid of pseudodiaphragm
Male gonotheca	Large, tubular in frontal view, laterally flattened, truncate distally (Galea et al. 2009, Fig. 2J), twice the length of the internode (Galea et al. 2009, Table 1)	Broadly club shaped, about 1.5 times the length of internode (Fraser 1937, Pl. 21 Fig. 111D)