Gonaxia sinuosa Vervoort, 1993

Galea, Horia R., 2016, Notes on some sertulariid hydroids (Cnidaria: Hydrozoa) from the tropical western Pacific, with descriptions of nine new species, European Journal of Taxonomy 218, pp. 1-52 : 11

Gonaxia sinuosa Vervoort, 1993

Figs 2E , 3 L–N

Gonaxia sinuosa Vervoort, 1993: 179 , figs 31c–e, 35b, 37a–b, 38a.

Material examined

SMIB 4: Stn. DW40, an originally 8 cm high colony with simple stem, now broken into two parts, bearing male gonothecae (MNHN-IK- 2012 -16526); Stn. DW48, an originally 5.5 cm high, sterile colony with simple stem, now broken into two unequal parts (MNHN-IK- 2012 -16527).

BATHUS 2: Stn. DW716, six colonies and fragments, 2.3–9.1 cm high, with simple or branched stems, two of which are sterile, two others bear male gonothecae, and the remaining two carry female gonothecae (MNHN-IK- 2012 -16528).

BATHUS 3: Stn. CP 804, eleven colonies and fragments, 1.5–4.9 cm high, all with simple stems, of which four are sterile, three bear male gonothecae, and the remaining four bear female gonothecae (MNHN-IK- 2012 -16529); Stn. DW829, two colonies with simple stems, 3.8 and 2.4 cm high, the latter devoid of its basal part, and bearing three incipient gonothecae (MNHN-IK- 2012 -16530).

Remarks

The shape of the hydrothecae ( Fig. 3L ), as well as the condition and morphology of the gonothecae ( Fig. 3 M–N) are characteristic. One stem from BATHUS 2, Stn. DW716 is fully fertile (male) and bears its gonothecae in two parallel rows, each one originating from below the base of an axillar hydrotheca. The female stems examined here bear a lesser number of gonothecae.

Geographical distribution

New Caledonia ( Vervoort 1993; present study), Norfolk Ridge ( Vervoort 1993).

Figures

Fig. 2. ― A. Gonaxia amphorifera Vervoort, 1993 (SMIB 6, Stn. DW127), portion of stem with cladium. ― B. Gonaxia ampullacea Vervoort, 1993 (BATHUS 4, Stn. DW914), portion of stem with cladia. ― C. Gonaxia compacta Vervoort, 1993 (BATHUS 4, Stn. DW923), portion of stem with cladium. ― D. Gonaxia intermedia Vervoort, 1993 (BATHUS 4, Stn. CP906), portion of stem with cladium. ― E. Gonaxia sinuosa Vervoort, 1993 (SMIB 4, Stn. DW40), portion of stem with cladia. Scale bar: A–E = 1 mm.

Fig. 3. ― A–B. Gonaxia amphorifera Vervoort, 1993 (SMIB6, Stn. DW127). A. Two successive cladial internodes with their hydrothecae. B. Portion of stem with male gonothecae. ― C–D. Gonaxia ampullacea Vervoort, 1993 (BATHUS 4, Stn. DW914). C. Two successive cladial internodes with their hydrothecae. D. Portion of stem with male gonothecae. ― E–F. Gonaxia compacta Vervoort, 1993 (BATHUS 4, Stn. DW923). E. Two successive cladial internodes with their hydrothecae. F. Abortive gonotheca (of undetermined sex) originating from within a hydrotheca. ― G–K. Gonaxia intermedia Vervoort, 1993 (BATHUS 4). G. Two successive cladial internodes with their hydrothecae (Stn. CP906). H. Portion of stem with male gonothecae (Stn. CP906). I. Portion of stem with female gonothecae (Stn. CP906). J–K. Abortive gonothecae arising from hydrothecal lumina (Stn. DW902). ― L–N. Gonaxia sinuosa Vervoort, 1993 (SMIB 4, DW40). L. Two successive cladial internodes with their hydrothecae. M–N. Two female gonothecae. Scale bars: A, C, E, G, L = 300 µm; B, D, F, H–K, M–N = 1 mm.