Hemimycale harlequinus, Sim-Smith & Hickman & Kelly, 2021

Sim-Smith, Carina, Hickman, Cleveland & Kelly, Michelle, 2021, New shallow-water sponges (Porifera) from the Galápagos Islands, Zootaxa 5012 (1), pp. 1-71 : 45-47

publication ID

https://doi.org/10.11646/zootaxa.5012.1.1

publication LSID

lsid:zoobank.org:pub:56C6852D-AAE0-4B6B-AB57-919CD62DAEC1

DOI

https://doi.org/10.5281/zenodo.5162308

persistent identifier

https://treatment.plazi.org/id/D3075148-FFF7-FFD5-FF67-8DD3B054C861

treatment provided by

Plazi

scientific name

Hemimycale harlequinus
status

sp. nov.

Hemimycale harlequinus   sp. nov.

( Fig. 21 View FIGURE 21 , Table 6)

Material examined. Holotype — MCCDRS9462, Guy Fawkes Island , 0.515° S, 90.527° W, 15 m, 10 Sep 2003 GoogleMaps   . Paratypes — MCCDRS9461, Guy Fawkes Island , 0.515° S, 90.527° W, 26 m, 26 Jul 2003 GoogleMaps   ; MCCDRS9463, Guy Fawkes Island , 0.515° S, 90.527° W, 18 m, 5 Feb 2003 GoogleMaps   . Other material— MCCDRS9465, Rabida Island , 0.406° S, 90.713° W, 14 m, 18 Nov 2003 GoogleMaps   ; MCCDRS9458, Cousins Rock, Santiago Island , 0.235° S, 90.574° W, 11 Nov 2003 GoogleMaps   ; MCCDRS9459, Daphne Minor Island , 0.394° S, 90.351° W, 17 m, 30 Jan 2004 GoogleMaps   ; MCCDRS9460, Gordon Rocks, Santa Cruz Island , 0.567° S, 90.142° W, 24 m, 20 Jul 2003 GoogleMaps   ; MCCDRS9457, Cape Marshall, Isabela Island , 0.018° S, 91.205° W, 30 m, 17 Nov 2003 GoogleMaps   ; MCCDRS9464, Los Hermanos Islands , 0.867° S, 90.782° W, 9 m, 18 Jan 2003 GoogleMaps   .

Type locality. Guy Fawkes Island   .

Habitat and distribution. Collected from Guy Fawkes Island, Gordon Rocks, Daphne Minor Island , Rabida Island ; Isabela Island , Santiago Island , Los Hermanos Islands ; 9–30 m. Commonly observed from the central archipelago, typically found growing on rock or black coral ( Antipathes galapagensis Deichmann, 1941   )   .

Description. Thinly encrusting sponge, base ≤ 15 mm thick, densely covered in trumpet-shaped papillae topped with circular to irregular, areolate porefields. Conspicuous single or septate cylindrical or volcano-shaped oscules, are frequently interspersed between the papillae. Papillae and oscules are delicate and membranous and collapse when preserved. Colour in life variable from cream to pink to orange, colour in ethanol tan ( Fig. 21A–D View FIGURE 21 ). A pink and cream form occurs where the encrusting base is pink and the areolate porefields are cream ( Fig. 21B View FIGURE 21 ). Texture of the main body is soft; papillae are brittle when preserved.

Skeleton. No defined ectosomal skeleton. The choanosome contains wispy, plumose tracts of megascleres that fan out into brushes at the surface ( Fig. 21E View FIGURE 21 ). The choanosome is filled with large cavities and scattered debris, spicule density is low ( Fig. 21F View FIGURE 21 ). Megascleres are primarily strongyles. Sharply curved sub/tylostyles are present at a much lower abundance. There is no differentiation between the location of the two types of megascleres.

Spicules. Megascleres— Strongyles, slender, occasionally faintly polytylote, with faint, subtylote tips that are often slightly inequiended; 275 (184–332) × 5 (2–8) µm (n = 120) ( Fig. 21G & I View FIGURE 21 ). Sub/tylostyles, curved with a rounded head and a sharply pointed tip; 286 (181–376) × 6 (4–11) µm (n = 120) ( Fig. 21H & J View FIGURE 21 ).

Etymology. Named for the variable colouration of the species (Latin nominative singular in apposition).

Remarks. Only seven species of Hemimycale   have been described, none of which are from the eastern Pacific. Initially, it was thought that the different coloured specimens might comprise several species, but the spicule complement and skeletal architecture are consistent between specimens. Colour variation is not unprecedented in the genus; the type species, H. columella ( Bowerbank, 1874)   , occurs in a similar colour range of pink, pale orange and bright red.