Macrorhynchia philippina Kirchenpauer, 1872

Gil, Marta & Ramil, Fran, 2025, Hydroids (Cnidaria, Hydrozoa) from Guinea Bissau, Zootaxa 5577 (1), pp. 1-89 : 60

Macrorhynchia philippina Kirchenpauer, 1872

( Fig. 10D )

Macrorhynchia (Aglaophenia) philippina Kirchenpauer, 1872: 45 , pl. 1 fig. 26, pl. 2 fig. 26, pl. 7 fig. 26.

Macrorhynchia philippina : Migotto, 1996: 40–43, fig. 8E–F.— Ansín Agís et al., 2001: 100–104, fig. 46.— Watson, 2002: 349, fig. 7A–B.— Calder & Kirkendale, 2005: 483–489.—Di Camilo et al., 2010: 214–217, figs 2E, G, 5A–G, 8G–L.— Chakraborty & Raghunathan, 2020: 300–303 , figs 2A, 5A–D.

Lytocarpus philippinus : Millard, 1958: 220.

? Macrorhynchia philippina : Schuchert, 2003: 221–223, fig. 67.

Lytocarpus crosslandi : Ritchie, 1907: 511–512, pl. XXIV fig. 11, pl. XXVI figs 2–4.

Material examined. BISSAU-0810, stn BS191, 10º18'25"– 10º19'20"N, 16º08'47"– 16º08'47"W, 24–25 m, 3- XI-2008: seven colonies without gonosome, 53 mm high, of which three growing on crustaceans and one on an unidentified hydroid.

Remarks. The small size of the colonies we studied could be related to the shallow depth at which they occurred. According to Watson (2002), colonies from shallow waters are smaller because they are under more exposed conditions than those living in deeper water.

The record of M. philippina from Kei Islands, Indonesia ( Schuchert 2003) is considered a possible synonym of Macrorhynchia fallax Galea & Maggioni, 2024 (original account).

Biology. Macrorhynchia philippina is a species with a high capacity of colonization ( Espino et al. 2020) and a habitat former ( Chakraborty & Raghunathan 2020). It has been collected from many different types of habitats and substrates, including rocky reefs, seagrass meadows, rhodolith seabeds ( Espino et al. 2020), hard substrates ( Watson 2002; Cinar et al. 2006), dead gorgonians, corals and ropes (Di Camilo et al. 2010). In the northern hemisphere, fertile material has been found in June, August and October ( Ansín Agís et al. 2001), while in the southern hemisphere the gonosome was observed in July ( Millard 1958, as Lytocarpus philippinus ).

In our material, some colonies were growing on crustaceans and an unidentified hydroid.

Distribution. This is a circumglobal species in tropical and subtropical waters ( Schuchert 2003; Di Camilo et al. 2010; Calder & Faucci 2021). In West Africa, it has been recorded from the Cape Verde ( Ritchie 1907, as Lytocarpus crosslandi ; Ansín Agís et al. 2001) and Guinea-Bissau ( Billard 1931a, as L. philippinus ). Its bathymetric distribution ranges from 1 to 411 m ( Ansín Agís et al. 2001).

Our material was collected from a depth of 24–25 m.

Genus Streptocaulus Allman, 1883

Figures

FIGURE 10. A–B. Aglaophenia tubulifera (Hincks, 1861) (stn BS157); portion of hydrocladium (A); corbula (B). C. Lytocarpia tridentata (Versluys, 1899) (stn BS191), portion of hydrocladium. D. Macrorhynchia philippina Kirchenpauer, 1872 (stn BS191), portion of hydrocladium. E. Halopteris catharina (Johnston, 1833) (stn BS134), portion of hydrocladium. Scales: a–e, 0.5 mm.