A key to the genera and species of the transversely-dividing Flabellidae (Anthozoa, Scleractinia, Flabellidae), with a guide to the literature, and the description of two new species
Author
Cairns, Stephen D.
text
ZooKeys
2016
562
1
48
http://dx.doi.org/10.3897/zookeys.562.7310
journal article
http://dx.doi.org/10.3897/zookeys.562.7310
1313-2970-562-1
D11C6C1E6EE74C8DA560331E75947EC8
D11C6C1E6EE74C8DA560331E75947EC8
Taxon classification Animalia Scleractinia Flabellidae
Truncatoflabellum duncani
sp. n.
Fig. 8C
Flabellum candeanum
:
Duncan 1864
: 163;
1870
: 300, pl. 20, fig. 1.
Truncatoflabellum candeanum
:
Cairns 1989b
: 61, pl. 36i-j.
Types.
Holotype: USGS 10809, Mornington,
Balcombe's
Bay, Victoria, Balcombian (Middle Miocene), USNM M353592. Paratypes: Muddy Creek, Victoria, Balcombian (Middle Miocene), 3 specimens, USNM 67959; Torquay,
Balcombe's
Bay, Victoria, Janjukian (Late Oligocene), 1 specimen, USNM 1295618; 3 miles (=4.8 km) west of river Gellibrand,
Otway's
region, Victoria, "Murray Tertiaries" (probably Middle Miocene) (specimen reported by Duncan, 1864, 1870), BM.
Description.
The anthocyathus has straight rounded thecal edges, with an edge angle of 54-72° and face angle of about 27°. The holotype is 30.8
x
18.1 mm in calicular diameter and 28.5 mm in height, with a greater scar diameter of 8.7 mm, similar in size to the specimen reported by Duncan. The GCD:LCD ratio is 1.5-2.1; the H:GCD = 0.95-1.05; and the GSD:GCD is about 0.27, with the scar reaching as long as 12 mm. Four or five pairs of prominent flattened thecal edge spines are present. The septa are quite regularly arranged in five cycles (S1-3>S4>S5), with one pair of S6 in each of the four end half-systems, resulting in 104 septa. The lower axial edges of the larger septa are only slightly sinuous, whereas the upper outer edges are gracefully attenuate, meeting the upper theca as low lamellae. The fossa is open, bordered by the axial edges of the wide S1-3. The anthocaulus is unknown.
Distribution.
Late Oligocene to Middle Miocene, Victoria.
Remarks.
As suggested by the key,
Truncatoflabellum duncani
is remarkably similar to
Truncatoflabellum multispinosum
, but can be distinguished by its attenuated upper septal margins. It is also known only from the Oligocene to Miocene of Australia, whereas
Truncatoflabellum multispinosum
is restricted to the Holocene and Late Pleistocene.
Etymology.
Named in honor Peter M. Duncan, who first discovered specimens belonging to this species.