Zygophylax abyssicola, (STECHOW, 1926)

Gu, Zhangjie, Ruthensteiner, Bernhard, Moura, Carlos J., Liu, Lihua, Zhang, Rui & Song, Xikun, 2022, Systematic affinities of Zygophylacidae (Cnidaria: Hydrozoa: Macrocolonia) with descriptions of 15 deep-sea species, Zoological Journal of the Linnean Society (Zool. J. Linn. Soc.) 196, pp. 52-87 : 60

ZYGOPHYLAX ABYSSICOLA ( STECHOW, 1926)

( FIGS 3 , 4 , 5A–F )

Lictorella abyssicola Stechow, 1926: 99 ; Ruthensteiner et al., 2008: 19.

Zygophylax abyssicola: Rees & Vervoort, 1987: 76 ; Galea & Schuchert, 2019: 59.

? Zygophylax bifurcata Billard, 1942: 34–35 , figs 1–3.

Type locality: Somalia, near Mogadishu, north-west Indian Ocean; 1644 m.

Specimens examined: Eight syntypes from the Indian Ocean, four of them with gonothecae; see details in Supporting Information, Table S1 .

Lectotype designation: Lectotype, a fertile, formalinfixed then ethanol-preserved colony, ZSM 20040197 ( Fig. 3A , arrow); paralectotypes, the remaining colonies from sample ZSM 20040197 ( Fig. 3A , the left colony, G), ZSM 20040726 ( Fig. 3A , the right colony, D), formalinfixed then ethanol stored, ZSM 20043537–20043542 ( Figs 3B, C, E, F, H, I , 5A–F ), microslides .

Figures

Figure 3. Type material of Zygophylax abyssicola (Stechow, 1926). A, B, colonies with dichotomous branching patterns, the arrow in A indicates the lectotype; C, a polysiphonic hydrocaulus; D, three successive nodes (arrows) on a hydrocladium, each internode bearing a hydrotheca; E, an axillary hydrotheca; F, a hydrotheca with diaphragm and renovations, and a nematotheca (arrow) near the hydrotheca; G, a coppinia; H, an isolated gonotheca, whose apex bears two apertures; I, a gonotheca with dichotomously branched defensive tubes. From samples: ZSM 20040197, paralectotype [A (left colony), G]; ZSM 20040197, lectotype [A (middle colony)]; ZSM 20040726, paralectotype [A (right colony), D]; ZSM 20043538, paralectotype (B, E); ZSM 20043539, paralectotype (C, F); ZSM 20043542, paralectotype (H, I). A–I, Indian Ocean. A–I, light microscope images. Scale bars: A = 1 cm; B = 0.5 cm; C, D, G, I = 1 mm; E = 0.5 mm; F, H = 200 µm.

Figure 4. Line drawings of Zygophylax abyssicola (Stechow, 1926). A, three successive nodes on a hydrocladium, each internode bearing a hydrotheca; B, an axillary hydrotheca; C, a hydrotheca, showing its diaphragm and renovations, and a nematotheca; D, an isolated gonotheca, whose apex bears two apertures; E, a gonotheca with dichotomously branched defensive tubes. Scale bars: A = 1 mm; B–D = 500 µm; E = 500 µm.

Figure 5. Type materials (all paralectotypes) of five Zygophylax species deposited in the Zoologische Staatssammlung München.A–F,Z. abyssicola (Stechow, 1926), ZSM 20043537–ZSM 20043542; G, H, Z. africana Stechow, 1923, ZSM 20041574, ZSM 20043579; I–M, Z. curvitheca Stechow, 1913, ZSM 20043570–ZSM 20043574; N–Q, Z. pacifica Stechow, 1920, ZSM 20041554–ZSM 20041556, ZSM 20043569; R–U, Z. valdiviae Stechow, 1923, ZSM 20041566–ZSM 20041569. Scale bars: A–U = 2 cm.