Mycale (Oxymycale) acerata Kirkpatrick, 1907

Goodwin, Claire E., Berman, Jade & Hendry, Katharine R., 2019, Demosponges from the sublittoral and shallow-circalittoral (<24 m depth) Antarctic Peninsula with a description of four new species and notes on in situ identification characteristics, Zootaxa 4658 (3), pp. 461-508: 492-493

publication ID

https://doi.org/10.11646/zootaxa.4658.3.3

publication LSID

lsid:zoobank.org:pub:D926CCEC-56EF-4E9A-98BE-CEB4D4D3D60A

persistent identifier

http://treatment.plazi.org/id/03B087ED-FFD6-FFB9-FF59-FCF5FBE9D8CB

treatment provided by

Plazi

scientific name

Mycale (Oxymycale) acerata Kirkpatrick, 1907
status

 

Mycale (Oxymycale) acerata Kirkpatrick, 1907 

( Figure 18View FIGURE 18)

Synonomy: Mycale acerata Kirkpatrick, 1907  ; Mycale acerata var. minor Hentschel, 1914  ; Mycale acerata var. sphaerulosa Hentschel, 1914  ; Oxymycale acerata ( Kirkpatrick, 1907)  .

Specimens. BELUM. Mc 2015.552 Gøuvernoren Wreck, Enterprise Island (64°32.407’S, 61° 59.884’W), depth 8–19 m; collected by C. Goodwin and E. Priestley, 12/02/2015GoogleMaps  ; BELUM. Mc 2015.604 Grotto Island , Verdansky Base (Site 1) (65°14.615’S, 64° 15.019’W), depth 14–24 m; collected by C. Goodwin and E. Priestley, 16/02/2015GoogleMaps  ; BELUM. Mc 2015.617 and  BELUM. Mc 2015.631 Grotto Island , Verdansky Base (Site 2) (65°14.529’S, 64° 15.451’W), depth 6–18 m; collected by C. Goodwin and E. Priestley, 16/02/2015GoogleMaps  ; BELUM. Mc 2015.649 Rocks near San Martin Islands (65°41.297’S, 65° 20.091’W), depth 6–21 m; collected by C. Goodwin and E. Priestley, 17/02/2015GoogleMaps  ; BELUM. Mc 2015.655 The Minnows, Prospect Point (66°01.642’S, 65° 21.323’W), depth 6–18 m; collected by C. Goodwin and E. Priestley, 17/02/2015GoogleMaps  .; BELUM. Mc 2015.660 Detaille Island (Site 1) (66°52.373’S, 66° 46.967’W), depth 6–24 m; collected by C. Goodwin and E. Priestley, 18/02/2015GoogleMaps  ; BELUM. Mc 2015.690 Rocks NW of Laktionov Island (65°45.536’S, 65° 47.319’W), depth 6–23 m; collected by C. Goodwin and E. Priestley, 22/02/2015GoogleMaps  ; BELUM. Mc 2015.697 and  BELUM. Mc 2015.710 Vieugue Island (65°38.758’S, 65° 12.540’W), depth 10–22 m; collected by C. Goodwin and E. Priestley, 23/02/2015GoogleMaps  ; BELUM. Mc 2015.731 Port Charcot, Booth Island (65°03.853’S, 64° 01.868’W), depth 6–16 m; collected by C. Goodwin and E. Priestley, 23/02/2015GoogleMaps  ; BELUM. Mc 2015.780 Under Spiggot Peak, Orne Harbour (64°37.755’S, 62° 33.018’W), depth 5–21 m; collected by C. Goodwin and E. Priestley, 25/02/2015GoogleMaps  ; BELUM. Mc 2015.807 Neptune’s Bellows, Deception Island (62°59.607’S, 60° 33.601’W), depth 7–18 m; collected by C. Goodwin and E. Priestley, 26/02/2015GoogleMaps  ; BELUM. Mc 2015.833 and  BELUM. Mc 2015.836 Diomedea Island (62°12.185’S, 58° 56.760’W), depth 10–18 m; collected by C. Goodwin and E. Priestley, 01/03/2015GoogleMaps  .

External morphology. In situ appearance  ( Figure 18AView FIGURE 18): Lemon yellow, massive, sponge, individuals can be very large - some of our specimens were over 60 cm in diameter. Large specimens are composed of a series of fused mounds, often these bear terminal oscules. The surface of the sponge is covered in small nodules ~ 5 mm in diameter, giving it a bumpy appearance ( Figure 18BView FIGURE 18).

Preserved appearance. Grey mass. Skeletal columns visible as distinct fibres ~ 0.5 mm across. Preserving alcohol coloured yellow.

Skeleton: Choanosomal skeleton plumo-reticulate formed of columns of oxea 10–20 spicules thick ( Figure 18CView FIGURE 18). Ectosome is composed of a mesh of fibres 4–8 spicules thick ( Figure 18DView FIGURE 18). Microscleres are abundant, the larger chelae form rosettes.

Spicules: Measurements from BELUM.Mc2015.780.

Oxeas ( Figure 18EView FIGURE 18): 629(679)748 by 16(22) 27 µm with abruptly pointed ends.

Anisochelae 1 ( Figure 18HView FIGURE 18): 69(79) 86 µm in rosettes. The lower alae bears a short, antenna-like, projection.

Anisochelae 2 ( Figure 18IView FIGURE 18): 33(45) 55 µm. The lower alae bears a single pointed tooth.

Microxeas ( Figure 18FView FIGURE 18) 30(84)111 by 1.6(2.1) 2.6 µm. Spindle shaped.

Tiny oxeas/raphides ( Figure 18GView FIGURE 18): 6.6(7.1) 7.8 µm.

Remarks. The spicule sizes reported for the type are oxeas 850 by 16 µm, chelae 105 and 47 µm, and trichodragmata 62 µm, although the tiny oxeas are not mentioned—these were not obvious in all of our specimens. Specimens produced a lot of slime on collection. Mycale acerata  was very abundant, present at most of our sampling sites, often in large quantities. It is one of the dominant species on the Antarctic Peninsula ( Kowalke 1998).

Mycale acerata  is faster growing than many other Antarctic sponges and has been demonstrated to increase 43–67% in terms of wet weight in a year, because of this, it is thought to be able to compete successfully against many slower growing benthic species and may become spatially dominant in some benthic environments ( Dayton et al. 1974). Populations seem to be regulated by predation, particularly that of the asteroids Perknaster fuscus Sladen, 1889  and Acodontaster conspicuus (Koehler, 1920)  .

Distribution. Mycale acerata  is common along the Antarctic Peninsula, and widespread around the Antarctic and sub-Antarctic (records from Wilheim II Coast, Wilkes Land, South Shetland Islands, Princess Ragnhild Coast, Lars Christensen Coast, Kerguelen, Macquarie Island, Bouvet Island, South Orkneys, South Georgia), as well as being recorded from the Falkland Islands, Chile and Argentina ( Koltun 1964; Brueggeman 1998; Rios et al. 2004; Hajdu et al. 2016). It has been recorded from 10–761 m + depth ( Brueggeman 1998).

BELUM

Ulster Museum, Belfast