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crests or spurs (not spines) occur along each thecal edge.
Corallum 26.7 x 14.4 mm in calicular diameter, 22.5 mm in
height, and 3.7 x 6.2 mm in basal scar diameter, making it the
largest specimen known. Edge angle 57°; inclination of lateral
faces, 33°. Theca white and somewhat rough, displaying
chevron-shaped epithecal growth lines that peak at the 24 S1-3.
Septa hexamerally arranged in 5 complete cycles, with 4
additional pairs of S6 in quarter-systems adjacent to the 2
principal septa (104 septa). S^g have vertical, sinuous inner
edges that attain the columella. Septal faces distinctively lined
with 15-18 low ridges oriented perpendicular to the septal
edge, each ridge bearing a series of low, triangular granules.
Ridges alternate in position with those on opposite face of same
septum. S4 about two-thirds width of an S^ and have poorly
formed, finely dentate inner edges that do not fuse with the
columella. S5 quite small, only about one-quarter width of an
S4. The 4 pairs of S6 are rudimentary. Fossa deep and elongate,
containing a well-formed, elongate columella about 2.1 mm
wide.
DISCUSSION.—All previously reported specimens of this
species were poorly preserved, either represented as fossils or
Recent specimens that were dead when collected. The
specimen described above is the largest known specimen and is
well preserved, making possible an improvement of the
original description. Truncatoflabellum carinatum is distinguished
from most congeners by having nonspinose but acutely
angled and crested thecal edges; a very small face angle,
especially near the basal scar, and a rather small basal scar. The
edge spines attributed to this species by Cairns (1989a) are
more accurately interpreted as low, discontinuous edge crests.
MATERIAL EXAMINED.—New Records: AIb-5311, 6,
USNM 40787; off Pescadores Islands, Formosa Strait, South
China Sea, 30-50 m, 1, ex CAS 74990. Previous Records:
Types of T. carinatum; F. rubrum of Yabe and Eguchi
(1942a,b): Pleistocene of Tonbe, Sizuoko-ken, 2, TIUS 29233;
Pliocene of Koti-ken, 1, TIUS 43434; F. rubrum stokesii of
Yabe and Eguchi (1942a), Soyo Maru-295, 1, TIUS 51220; F.
rubrum of Yabe and Eguchi (1942a), Soyo Maru-222, 3, TIUS
50232.
TYPES.—The holotype and most paratypes of T. carinatum
are deposited at the USNM; 1 paratype is also at the Australian
Museum. Type Locality: Alb-5312:21 °30 / N, 116°32'E (north
of Pratas Island, South China Sea), 256 m.
DISTRIBUTION.—Recent: Formosa Strait north of Pratas
Islands, South China Sea; southeastern coast of Kyushu; Tusa
Bay, Shikoku; 30-274 m. Pliocene-Pleistocene of Honshu and
Shikoku, Japan.
Truncatoflabellum gardineri Cairns, 1993
PLATE 34ajj
Truncatoflabellum gardineri Cairns in Cairns and Keller. 1993:266, figs.
11B-D.
DESCRIPTION.—Coralla elongate and compressed, having a
relatively low thecal edge angle of 21°-39°, the thecal edges
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY
becoming almost parallel in upper region of some coralla.
Inclination of thecal faces, 18°-23°. Largest specimen from
Japan (TM (KT9202, OS3) 16.7 x 11.3 mm in calicular
diameter and 19.8 mm in height, with a basal scar diameter of
3.7 x 4.5 mm. Calicular edge smooth; GCDrLCD = 1.30-1.48.
Basal scar of anthocyathus rather small and elliptical, almost
circular, ranging from 4.5-4.7 x 3.3-3.7 mm in diameter.
Thecal edges rounded except for region approximately 3-10
mm above basal scar, which extends as a single narrow crest up
to 2.5 mm in height. Theca bears narrow longitudinal striae
corresponding to each septum as well as chevron-shaped
growth lines that peak at all but last septal cycle. In one
well-preserved corallum, the theca was reddish brown with an
indication of longitudinal striping along the major septa.
Septa hexamerally arranged in 4 complete to 5 incomplete
cycles according to the formula: S1_2>S3>S4>S5. Coralla less
than 11 mm GCD usually have 48 septa arranged in 4 complete
cycles. Between a GCD of 11-14 mm pairs of S5 begin to
appear in the quarter-systems directly adjacent to the 2
principal septa (50-56 septa) with a corresponding increase in
the width of the flanked S4 to the size of an S2 and the
acceleration of the adjacent S3 to the size of an Su2. Above a
GCD of 15 mm additional pairs of S5 may occur in the
remainder of the end half-systems and even quarter-systems
adjacent to those, up to a total of 66 septa. S,_2 w 'de and have
thickened, sinuous lower inner edges that fuse with the
columella. S3 about half width of S1-2 and do not attain the
columella, unless it is adjacent to an S5 (see above), in which
case it is almost as wide as an S1-2 and fuses with the
columella. S4 small, only about one third width of an S3, larger
if flanked by a pair of S5. S5 rudimentary. Septa widely spaced,
separated from one another by 2-3 septal thicknesses. Fossa
deep and narrow, containing a well-developed elongate fossa
about 1.8 mm wide.
DISCUSSION.—The only differences between the Japanese
specimens of T. gardineri and the type series of that species
from off Durban, South Africa is that the Japanese specimens
are larger and thus have more septa. The largest South African
specimens of 11-12 mm GCD have 56 septa, which is
consistent with the number of septa of a Japanese specimen of
equivalent size.
Truncatoflabellum gardineri is most similar to T. carinatum,
both species having acutely angled thecal edges that bear low
crests (not spines), but T. gardineri can be distinguished by
having only one pair of edge spines, virtually parallel thecal
edges, and fewer septa (see Key 2).
MATERIAL EXAMINED.—New Records: TM (KT9015,
CB6-1), 1, USNM 92807; TM (KT9202, KB3), 3, USNM
92808; TM (KT9202, OS3), 17, USNM 92809, 2, ORI.
Previous Records: Types of T. gardineri.
TYPES.—The holotype and most paratypes of T. gardineri
are deposited at the USNM (91736, 91737); 3 paratypes are
also deposited at the South African Museum. Type Locality:
Anton Bruun-390S: 29°34'S, 31 ^'E (off Durban, South
Africa), 138 m.