A Generic Revision and Phylogenetic Analysis of the Primnoidae

38 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY
Etymology. Greek pyros = fi re + gorgia, an
allusion to Tierra del Fuego. Gender: feminine.
Type Species. Fannyella lemnos Bayer, 1998,
here designated. The holotype is deposited at the USNM
(58392).
21. Amphilaphis Studer and Wright
in Studer, 1887
FIGURE 10J–Q
Amphilaphis Studer and Wright in Studer, 1887:50–51.—Wright and Studer,
1889:xlix, 70–71.—Versluys, 1906:20–22.—Kinoshita, 1908e:49–50 [key
to genus].—Thomson and Mackinnon, 1911:680.—Bayer, 1981b:936 [key
to genus].
Thouarella.—Kükenthal, 1912:307 [in part: “regularis-Gruppe”].
Thouarella (Amphilaphis).—Kükenthal, 1915:149 [key to subgenus and species];
1919:407–409 [key to subgenus and species]; 1924:288–289 [key to
subgenus and species].
Diagnosis. Colonies uniplanar, alternately
pinnately branched. Calyces arranged in irregular spirals
along branch (Figure 10j) or isolated; calyces inclined upward.
Well-developed operculum present; inner face of
operculars bears multiple ridges. Marginals arranged in
two circles of four that alternate with one another, the
circumference of distal polyp not being large enough to
accommodate eight marginal scales; eight marginal scales
fold over bases of operculars forming a circumoperculum;
distal edges of marginals pointed (Figure 10m). Polyps
protected by eight longitudinal rows of equal-sized body
wall scales that completely cover polyp; body wall scales
radially ridged on outer and inner surfaces (Figure 10n–o).
Coenenchymal scales in two layers: outer layer composed
of irregularly shaped scales with serrate edges, inner layer
composed of small spheroids.
Discussion. Originally described as a separate
genus, Amphilaphis was later considered by Kükenthal
(1915) to be a subgenus, but it was fi nally reestablished
as a genus by Bayer (1981b) but curiously ignored by him
in later general works (Bayer, 1956; Bayer and Stefani,
1989). Amphilaphis differs from Thouarella in having
eight complete longitudinal rows of equal-sized body wall
scales and pinnately branched colonies. The six species
currently assigned to the genus are tentatively placed there
at best, as the genus is badly in need of revision. The diagnosis
above is based on the type species.
Distribution. Tristan de Cunha, Bouvet I.,
Galápagos, Antarctic, Hawaii, 55–3,182 m.
Type Species. A. regularis Wright and Studer,
1889, by subsequent monotypy (Wright and Studer,
1889). Syntypes are deposited at the BM (1889.5.27.60,
1889.7.5.1-15, 1894.11.20.1, 1932.12.8.7); a fragment of
the type is also deposited at the ZMA (Coel. 3085) (van
Soest, 1979) and as SEM stub B576 (USNM).
22. Mirostenella Bayer, 1988
FIGURE 10R–A′
Mirostenella Bayer, 1988:251–252.—Bayer and Stefani, 1989:454 [key to
genus].
Diagnosis. Colonies branch in a regular, planar,
dichotomous manner, the calcifi ed axis interrupted by
organic nodes at points of bifurcation. Calyces arranged in
pairs or whorls of three or four, the calyces inclined slightly
upward (Figure 10r); brooding polyps common. Welldeveloped
operculum present, operculars smooth (not
keeled or ridged) on distal portion of inner surface (Figure
10w). Eight elongate marginals, each with a prominent
spine (Figure 10x–y), form a nonfolding crown around the
operculum. Polyps completely covered by eight rows of
body wall scales, these scales becoming smaller and somewhat
disorganized toward base of calyx. Outer surface of
all sclerites except for coenenchymals smooth. Coenenchymals
arranged in one layer, their outer surface covered with
coarse granules (Figure 10z, a′), as in Acanthoprimnoa.
Discussion. An additional specimen from
close to the type locality is reported herein, which allows
a proper illustration of polyp morphology (Figure 10r–a′)
as well as an extension of the depth range: R/V Prof.
Siedlecki 610-29, 54°32′S, 39°05′W, 201–210 m, 3 December
1986, USNM 84344.
In an unpublished manuscript, Bayer diagnosed a
second species of Mirostenella from three stations off the
Falkland Islands (493–1,647 m), differing from the type
species in having alternately pinnately branched colonies,
much longer marginal scales, and lack of organic nodes
at the branching axils. He thus implied that the peculiar
organic nodes of Mirostenella may be only of species level
value. Mirostenella is thus keyed twice in the key to the
genera, allowing for both branching morphologies. A third
species is also placed in the genus as a new combination,
M. delicatula (Thomson and Rennet, 1931), from Macquarie
Island. The type is deposited at the AM (G13266).