Tridentata loculosa ( Busk, 1852 )

Gil, Marta & Ramil, Fran, 2025, Hydroids (Cnidaria, Hydrozoa) from Guinea Bissau, Zootaxa 5577 (1), pp. 1-89 : 52-54

Tridentata loculosa ( Busk, 1852)

( Fig. 9A )

Sertularia loculosa Busk, 1852: 393–394 .— Migotto, 1996: 71–73, fig. 13f–i.— Schuchert, 2003: 188–189, fig. 42.— Galea,

2008: 35, fig. 6f–g. Tridentata loculosa : Calder, 2013: 31, fig. 9d. Sertularia ligulata : Vervoort, 1959: 277–279, fig. 37.—Millard, 1975: 307–309, fig. 100a–d.— Hirohito, 1995: 213–215, fig.

71a–g.

Material examined. BISSAU-0810, stn BS191, 10º18'25"– 10º19'20"N, 16º08'47"– 16º08'47"W, 24–25 m, 3-XI-2008: 565 colonies without gonothecae, 8–95 mm high, of which 121 growing on bryozoans, 97 on Idiellana pristis , 57 on Diphasia digitalis , 13 on crustaceans, 10 on Eudendrium capillare , nine on unidentified hydroids, five on worm tubes, two on Thyroscyphus marginatus , one on Plumularia setacea and one on a bivalve.

BISSAU-0810, stn BS192, 10º19'30"– 10º20'15"N, 16º10'27"– 16º10'59"W, 24 m, 3-XI-2008: 38 colonies without gonothecae, 15–64 mm high, of which one growing on a worm tube.

BISSAU-0810, stn BS193, 10º21'13"– 10º21'51"N, 16º10'17"– 16º10'56"W, 20–21 m, 3-XI-2008: 13 colonies without gonothecae, 1–27 mm high, of which 10 growing on bryozoans and one on Idiellana pristis .

BISSAU-0810, stn BS194¸ 10º21'59"– 10º22'36"N, 16º13'23"– 16º14'03"W, 21–24 m, 3-XI-2008: 11 colonies (three with gonothecae), 7–20 mm high, of which five growing on bryozoans, two on Eudendrium sp , one on Eudendrium ramosum and one on Idiellana pristis .

BISSAU-0810, stn BS195, 10º22'44"– 10º23'22"N, 16º15'37"– 16º16'18"W, 29 m, 3-XI-2008: 16 colonies without gonothecae, 16–36 mm high, of which six growing on bryozoans and two on Idiellana pristis .

Remarks. Our material agrees with that described by Gil & Ramil (2023b) from the Republic of Guinea. No further discussion is necessary.

Biology. This species has been found growing on stones ( Billard 1931b, as Sertularia loculosa ), algae, hydroids, bryozoans and barnacles ( Vervoort 1959; Migotto 1996, both as Sertularia ligulata ). In the southern hemisphere, fertile colonies have been found between January–March and June ( Migotto 1996, as S. ligulata ).

In our material, some colonies were growing on hydroids, bryozoans, worm tubes, bivalves and crustaceans; in addition, some of them were auto-epizoic. Gonothecae were found in the northern hemisphere in November for the first time.

Distribution. Tridentata loculosa is a circumtropical species ( Calder 2013), with a bathymetric distribution ranging from 0 ( Galea 2008) to 155 m ( Migotto 1996). In West Africa, it has been recorded from Guinea-Bissau ( Billard 1931a) to the Ivory Coast ( Redier 1965, as S. ligulata ).

Our material was collected at depths between 20–29 m.

Figures

FIGURE 9.A. Tridentata loculosa (Busk, 1852) (stn BS199), portion of stem. B–D. Tridentata marginata (Kirchenpauer, 1864) (stn BS195); portion of colony (B); gonothecae (C–D). E. Tridentata rugosissima (Thornely, 1904) (stn BS193), portion of stem. F. Tridentata turbinata (Lamouroux, 1816) (stn BS191), portion of stem. Scales: a–f, 0.5 mm.