Notophyllia hecki, Cairns, 2004

Cairns, S. D., 2004, The Azooxanthellate Scleractinia (Coelenterata: Anthozoa) of Australia, Records of the Australian Museum 56, pp. 259-329 : 317

Notophyllia hecki n.sp.

Figs. 12D,E,H–K

Records/Types. Holotype: Franklin 03/99/D12, AM G16749 . Paratypes: Franklin 03/99/D10, 4, USNM 1008866 ; Franklin 03/99/D11, 36: 34, USNM 1008867 (including SEM stub 1020) and 2, ZMUZ; Franklin 03/99/ D12, 7, USNM 1008868 ; Franklin 03/99/D13, 2, USNM 1008869 ; Franklin 03/99/D14, 1, USNM 1008870 . Type

Locality: 20°14.629'S 151°59.081'E ( Marion Plateau , Queensland), 367 m.

Description. Corallum (anthocyathus) compressed-conical, with rounded thecal edges and faces, and a bluntly pointed base. GCD:LCD of larger specimens ranges from 1.16 to 1.32; small coralla, just above the basal transverse fracture, are more elliptical in cross-section, having a GCD:LCD of 1.5–1.6. Largest specimen (holotype) 3.45× 2.71 mm in CD and 4.7 mm in height. Lower 1.3–1.5 mm of anthocyathus, corresponding to a GCD of 1.7–2.3 mm, represents that portion of the anthocyathus that was former immersed in the anthocaulus (basal scar region). Theca composed of alternating longitudinal regions of wide (0.3 mm) highly spinose and porous strips that correspond to septa and narrower (0.1 mm wide) flat, non-spinose strips corresponding to interseptal spaces. Spines of thecal costal regions prominent, up to 0.15 mm in height, and interspersed with rather large (0.1 mm diameter) irregularly shaped thecal pores (the synapticulotheca, Fig. 12J). Anthocaulus also compressed, reaching a height of about 2.1 mm and a GCD of 1.7–2.4 mm before budding an anthocyathus. Anthocaulus free, also with a blunted base.

Septa hexamerally arranged in 3 cycles, S3 not present in 2 lateral systems, which results in 20 septa. This number is present even in the smallest of anthocyathi, but anthocauli appear to be restricted to only 12 septa. S1 slightly exsert (0.45 mm), rather slender (extending only about half the distance to the columella in upper fossa), and have axial edges that fuse to the columella lower in the fossa, the 4 lateral S1 fusing slightly higher than the 2 principal S1. S2 less exsert (0.25 mm) and quite small, about one-sixth the width of an S1, at least in large coralla. In small coralla, S2 almost same width as S1. The 8 S3 are equally as small as the S2, each pair bending toward and fusing to its adjacent S2 quite low in the fossa, the axial edge of each S2 then usually fusing to the axial edge of the adjacent S1 (in the case of the end systems) or the columella (in the case of the 2 lateral systems). Axial edges of S1 smooth and slightly sinuous, whereas those of the S2–3 irregular and sometimes laciniate. Fossa quite deep and capacious, containing a thin (0.15 mm), rather short (0.7 mm), lamellar columella, rarely extending beyond the location of the 4 lateral S1.

Remarks. All seven species of Notophyllia are endemic to the southern and eastern coasts of Australia, four of which are known only from the Middle Miocene of Victoria, Australia ( Cairns, 2001a). Notophyllia hecki most closely resembles N. aperta Dennant, 1899 , a species known only from the two Middle Miocene (Balcombian) of Victoria. Only these species have the same number of septa (20) arranged in the same pattern (6: 6: 8), and a relatively low GCD:LCD ratio. Notophyllia hecki differs from this, as well as all other known species, by having a pointed or conical anthocyathus base (vs fish-tailed or straight-keeled), and a very low GCD:LCD ratio, approaching circularity in larger specimens. Notophyllia hecki is also the smallest of the eight species with a GCD max. of 3.45 mm, that of N. apertum being 6.0 mm.

Etymology. Named in recognition of Philipp Reza Heck, who collected and made available for study a large collection of deep-water corals from the Marion Plateau.

Distribution. Known only from Marion Plateau, Queensland, 342– 414 m.