Hymerhabdia imperfecta Bertolino

Bertolino, Marco, Costa, Gabriele, Bavestrello, Giorgio, Pansini, Maurizio & Daneri, Giovanni, 2020, New sponge species from Seno Magdalena, Puyuhuapi Fjord and Jacaf Canal (Chile), European Journal of Taxonomy 715, pp. 1-49 : 7

Hymerhabdia imperfecta Bertolino , Costa & Pansini sp. nov.

urn:lsid:zoobank.org:act:FF9FC2BD-D935-4B83-B345-228C74D457B2

Fig. 2 ; Table 3

Etymology

The new species is named after the presence of imperfect rhabdostyles.

Type material

Holotype

CHILE – Puerto Cisnes • Seno Magdalena E; 44.613885° S, 72.94149° W; depth 30 m; 5–10 Aug. 2016; Marco Bertolino leg.; on a rocky cliff by scuba diving; CILE 63 ; MSGN 60889 .

Paratype

CHILE – Puerto Cisnes • 1 specimen; Seno Magdalena F (Punta Angostura) ; 44.6312,35° S, 72.904239° W; depth 25 m; 5–10 Aug. 2016; Marco Bertolino leg.; on a rocky cliff by scuba diving ; CILE 43; DISTAV.

Description

HABITUS. Encrusting, 5 mm thick and 5 cm long ( Fig. 2A ). Surface rugose and hispid, with visible canals converging towards oscules. Colour in life bright orange ( Fig. 2A ). Consistency of live specimens friable.

SKELETON. Choanosomal skeleton formed by bundles of long styles and tylostyles with heads embedded in basal layer of rhabdostyles and sinuous sub-tylostyles.

SPICULES. Megascleres: Smooth styles, long and thin, sometimes with modified heads ( Fig. 2B ), 800– (888.33)–1000 μm long and 5–(7.16)–10 μm thick. Smooth tylostyles 410–(552.5)–700 μm long and 15–(18.9)–25 μm thick ( Fig. 2C ). Rather short rhabdostyles with heads variable in shape and with pointed or round extremities ( Fig. 2D ), 140–(252.42)–415 μm long and 7.5–(9.75)–12.5 μm thick. Rhabdostyles often sinuous or modified into oxeas or strongyles ( Fig. 2E ).

Habitat

Species lives on a rocky cliff at a depth of 25–30 m; Chilean fjords.

Remarks

Out of the nine species of Hymerhabdia previously described around the world ( Table 3 ), none have been recorded along Chilean coasts. The only species of this genus from the Southern Hemisphere is Hymerhabdia oxeata (Dendy, 1924) recorded at a depth of 183 m in northern New Zealand. Hymerabdia imperfecta sp. nov. differs from H. oxeata in having a red colour whereas in H. oxeata the colour is dark brown. As to spicules, H. oxeata has oxeas whereas the new species has tylostyles and rhabdostyles that are not present in H. oxeata . Moreover, the styles of the new species are much larger ( Table 3 ). A comparison with the other 8 species of Hymerhabdia (from the Atlantic Ocean and the Mediterranean Sea reported in Table 3 ) shows remarkable differences in presence or absence of spicules (oxeas, rhabdostrongyles, toxostrongyles) and in their shape and size.

Figures

Fig. 2. Hymerhabdia imperfecta Bertolino, Costa & Pansini sp. nov., holotype (CILE 63; MSGN 60889). A. The holotype in life. B. Smooth styles. C. Smooth thicker tylostyles. D. Rhabdostyles. E. Rhabdostyles are often sinuous or modified in oxeas or strogyles.