Mycale (Mycale) lingua Bowerbank, 1866

Dinn, Curtis, Edinger, Evan & Leys, Sally P., 2019, Sponge (Porifera) fauna of Frobisher Bay, Baffin Island, Canada with the description of an Iophon rich sponge garden, Zootaxa 4576 (2), pp. 301-325 : 313-315

Mycale (Mycale) lingua Bowerbank, 1866

Figure 5 ; Table 5

Synonymy:

Hymeniacidon lingua Bowerbank, 1866: 187 –190.

Desmacidon constrictus Bowerbank, 1866: 187 –190.

Esperella vosmaeri Levinsen, 1887: 358 –359 pl.XXX fig 11–14.

Esperia lucifera Schmidt 1873: 148 .

Esperia placoides Carter 1876: 316 –317; pl XIII fig 12, pl XV fig 32.

Mycale (Mycale) lingua: Topsent 1924: 85 –88, Ackers et al. 1992: 111 –112., Boury-Esnault et al. 1994: 96, fig. 70. Van Soest et al. 2014: 99.

Material examined. CMNI 2018-0167 , s pecimen in 95% ethanol. Collected by Agassiz Trawl July 14, 2017, 402 m depth (62° 57.232’ N, 67° 08.360’ W) .

Specimens collected outside of Frobisher Bay: CMNI 2018-0053 , specimen in 95% ethanol. Collected by Curtis Dinn with BX 650 MK III box core July 15, 2016, 459m depth (63° 06.67’ N, 67°31.10’ W) . CMNI 2018 - 0 0 71, s pecimen in 95% ethanol. Collected by ROV hydraulic manipulator July 19, 2016, 631 m depth (61° 26.417’ N, 60° 39.8484’ W) . CMNI 2018-0152 , specimen in 95% ethanol. Collected by Curtis Dinn by ROV hydraulic manipulator July 25, 2016, depth 876 m (67° 58.0424’ N, 59° 29.0396’ W) . CMNI 2018-0196 , specimen in 95% ethanol. Collected by Agassiz trawl July 25, 2017, 333 m depth (76° 19.020’ N, 75° 46.225’ W) . All operations performed from the CCGS Amundsen in Frobisher Bay and Davis Strait, Canada .

Description. Specimens are bright yellow with a characteristic fibrous root and soft, furrowed distal portion ( Fig. 5 A–B). Spicules ( Fig. 5 C–L) consist of styles/mycalostyles 514 (400–590) x 16 (12–20) µm; sigmas 20 (14.5–26) µm, anisochelae I 73 (52–88) µm; anisochelae II 37.5 (28.5–50) µm; and raphides which were rare and did not form conspicuous trichodragmas in the Frobisher Bay specimens 43 (30–53) µm n=16. Interestingly, some modified anisochelae were present where the alae were not fully developed ( Fig. 5G, H ). These spicules occurred in both size categories, but only in the Frobisher Bay specimens.

Taxonomic Remarks. The spicule sizes of this specimen correspond to descriptions of M. lingua by Ackers et al. (1992). Descriptions by Boury-Esnault et al. (1994) and Van Soest et al. (2014) are also similar except that a third category of small anisochelae described in those publications is not present in this specimen ( Table 5); however, those specimens were found in more southern latitudes. Trichodragmas are not common, but often 2–3 raphides are seen attached to one another. In situ photos of specimens agree with descriptions by Ackers (1992) of a sulcate, furrowed surface that resembles the “tongue of a sheep”.

Discussion. This is the first record of Mycale lingua in Frobisher Bay. The species was collected once from Baffin Bay/Davis Strait by Lundbeck (1905) (70° 24 N, 63° 35 W, 497 m depth), further south on the southern Grand Banks (46° 4.6667 N, 49° 2.5 W, 1267 m depth) by Topsent (1892) and in the Gulf of Saint Lawrence (Brunel et al. 1998), and the Bay of Fundy ( Goodwin 2017). The spicules of the Frobisher Bay specimens are slightly smaller than those of separate specimens collected at 631 m (61° 26.417 N, 60° 39.8784 W) and 876 m (67° 58.0382N, 59° 29.0396 W) in Baffin Bay. The styles of these specimens are ~600 µm long and the anisochelae occur in two sizes (~87 µm and ~40 µm long). Ackers (1992) states that the furrowed grooves on the surface of the sponge are highly characteristic, and so despite the slight spicule variations, both specimens are best assigned to M. lingua .

Figures

FIGURE 5. Mycale lingua. A. Specimen collected. B. Sponge in situ, scale bar is 6 cm. C, D. Style/mycalostyles. E–G. Anisochelae I. H–J. Anisochelae II. K. Sigma. L. Raphide.