Halopteris violae Calder, Mallinson, Collins & Hickman, 2003

Mendoza-Becerril, María A., Estrada-González, Mariae C., Mazariegos-Villarreal, Alejandra, Restrepo-Avendaño, Luisa, Villar-Beltrán, Rogelio D., Agüero, José & Cunha, Amanda F., 2020, Taxonomy and diversity of Hydrozoa (Cnidaria, Medusozoa) of La Paz Bay, Gulf of California, Zootaxa 4808 (1), pp. 1-37 : 13-14

Halopteris violae Calder, Mallinson, Collins & Hickman, 2003

Figs. 5 F–K

Type locality. Bartolomé , Galápagos ( Calder et al. 2003) .

Material examined. Polyp—PB6_3, sampling site 2 (1), mature, on coralline alga Amphiroa valonioides Yendo ; PB7_29, sampling site 1 (1), immature, 27°C, on coralline alga Amphiroa beauvoisii J.V.Lamouroux ; PB7_35, sampling site 2 (1), immature, 27°C, substrate unknown; PB7_40, sampling site 3 (1), immature, 26.5°C, on rock and algae.

Description. Colonies from 7 to 13 mm high, monosiphonic, arising from a creeping hydrorhiza. Exoskeleton with visible layer corresponding to perisarc. Perisarc of hydrocaulus thick basally and thinner distally (1.0– 9.8 µm wide). Basal part of hydrocaulus without hydrothecae and hydrocladia; remainder of hydrocaulus longer (~ 9 mm long), regularly divided into internodes by straight nodes, with thecate and athecate internodes. Athecate internodes 240.3–295.3 µm long, with one median nematotheca and two nematothecae on either side of stem; thecate segments 317.7–340.0 µm long, each with one proximal nematotheca, one hydrotheca, two nematothecae lateral to hydrotheca, one median distal nematotheca, and two distal lateral nematothecae. Hydrocladia with two to six hydrothecae, unbranched, 1–3.4 mm long, directed outwards at an angle of 30–40° from axis of hydrocaulus, with a series of one short athecate internode with no nematothecae, one athecate internode with two median nematothecae and one thecate internode with one proximal nematotheca, a distal hydrotheca, and two lateral nematothecae. All nematothecae bithalamic. Hydrothecae 136.0– 191.3 µm deep, cup-shaped, axis oblique to that of internode, margin entire, aperture circular, diameter 123.3–154.2 µm. Gonotheca clavate, 596.2–625.4 µm long, 189.0– 194.7 µm wide, aperture 145.1 µm wide; with two-segmented pedicel, arising from the base of hydrotheca on hydrocladia; exoskeleton corresponding to thin perisarc (2.0– 3.8 µm wide); base of gonotheca with two nematothecae.

Nematocysts (length x diam.). Microbasic mastigophores (8.2–10.0 x 3.6–4.4 µm).

More detailed description in Calder et al. (2003).

Taxonomic status. Accepted. AphiaID 287325.

Distribution. Pacific Ocean ( Calder et al. 2003). This is a new record for the Mexican Pacific.

literature descriptions.

Figures

FIGURE 5. A–E Antennella secundaria (Gmelin, 1791): A, basal part of hydrocladium; B, internode; C, hydrotheca and nematotheca; D, gonothecae; E, nematocysts microbasic mastigophore. F–K Halopteris violae Calder, Mallinson, Collins & Hickman, 2003: F, monosiphonic colony; G, hydrocaulus and hydrocladia; H, hydrotheca of hydrocaulus; I, nematothecae; J, gonothecae; K, nematocysts microbasic mastigophores. Scale equals A, D, H, J—200 µm; B, C, I—50 µm; E—13 µm; F—3 mm; G—500 µm; K—17 µm.