A Review of the Genus Eunice - Smithsonian Institution Libraries

NUMBER 523 253
the type, there is little in the numerically arranged features that
appears unique and the setal structures are similar to what is
present in several species. Six species in Table 21 have
articulated ceratostyles; of these only E. parasegregata and E.
tridentata have moniliform or drop-shaped articulations distally
in the ceratostyles; the other four species have cylindrical
articulations to the tips of the antennae. In E. parasegregata the
appendages of the compound falcigers are tapering, not
particularly small in relation to the shafts of the falcigers; in E.
tridentata the appendages are very small, slender, and barely
tapered. Eunice parasegregata is easily separated from other
species in Table 23, because it has as many as 18 branchial
filaments; of other species in this table, E. johnsoni comes the
closest with 10 filaments where the branchiae are best
developed.
The dorsal aciculae of setiger 2 were illustrated by
Hart man n-Schroder as strongly curved; this observation cannot
be confirmed without damaging the specimen severely, but
would, if confirmed, represent a wholly unique feature to this
species.
The structure of median and posterior parapodia is unusual,
but the relation between these features and conditions of
preservation have yet to be elucidated.
The numbers of maxillary teeth reported here are slightly
higher than those reported by Hartmann-Schrftder (1965b); the
basal teeth are very small and easily overlooked.
Eunice parca Grube, 1878a:99.
Eunice parca Grube, 1878
REMARKS.—This species was listed in Grube's tabularly
formatted paper as having branchiae limited to the anterior and
median part of the body and distinctly articulated antennae. No
further description was given, no locality was indicated, and no
specimens are available in German or Polish collections. The
species is here considered indeterminable rather than as a
nomen nudum, because some indication of its features has been
given by its position in Grube's paper.
206. Eunice parva Hansen, 1882
FIGURE 84a-h; TABLES 41,44
Eunice parva Hansen, 1882:7, pi. 2: figs. 4-7.
MATERIAL EXAMINED.—Holotype, ZM Leiden, no. 1481,
Rio de Janeiro, coll. E. v. Beneden.
COMMENTS ON MATERIAL EXAMINED.—The holotype is
now in two pieces and the anterior end has been ventrally
dissected.
DESCRIPTION.—Holotype complete, of unknown sex, with
59 setigers; total length 17 mm; maximal width 0.75 mm at
setiger 10; length through setiger 10, 4 mm. Body anteriorly
cylindrical; posterior half dorsoventrally flattened, anteriorly
truncate, posteriorly slowly tapering to the posterior end.
Pygidium damaged; only short anal cirri present.
Prostomial lobes frontally rounded, dorsally inflated; median
sulcus shallow. Palpal region set off by horizontal frontal
grooves. Prostomium distinctly narrower than peristomium,
shorter than peristomium and more than half the depth of the
peristomium. Eyes behind bases of A-II, faded purple.
Antennae in horseshoe, evenly spaced, similar in thickness.
Ceratophores short, ring-shaped. Ceratostyles tapering; maximum
12 moniliform articulations in A-II I. A-I to posterior edge
of anterior peristomial ring; A-II to setiger 3; A-III to setiger 5.
Anterior peristomial ring tapering anteriorly; posterior peristomial
ring cylindrical. Nuchal fold with lateral notches; lower lip
with medial notch. Separation between rings distinct dorsally
and ventrally; anterior ring 2 /3 of total peristomial length.
Peristomial cirri to posterior edge of prostomium, slender,
tapering, with 2 distinct articulations.
Jaws missing; maxillary formula 1+1 4+7, 10+0, 5+7, and
1+1 according to Hansen (1882, pi. 2: fig. 6). Mx III long,
straight, located behind left Mx II. Left Mx IV short, curved.
Mx VI missing.
Branchiae from setiger 5 to setiger 20; first 2 and last 2 pairs
single filaments; maximum 4 filaments at setiger 10. Branchiae
longer than notopodial cirri. Stems slightly shorter than
notopodial cirri, cylindrical, erect. Filaments slightly shorter
than notopodial cirri, digitiform, slightly thinner than notopodial
cirri.
Anterior neuropodial acicular lobes asymmetrically truncate;
median and posterior acicular lobes asymmetrically rounded;
all with aciculae emerging from upper edge. Pre- and postsetal
lobes low, transverse folds. First 4 ventral cirri tapering,
thereafter basally inflated; inflated bases large, spherical. Free
tips tapering; ~ l /i as wide as the inflated bases. Inflated bases
decreasing from about setiger 20; totally absent from about
setiger 30. Posterior ventral cirri longer than those in anterior
setigers, digitiform or slightly tapering, distinctly shorter than
notopodial cirri. Anterior notopodial cirri tapering with 4 to 5
distinct articulations; articulations lost in early branchial
setigers; notopodial cirri gradually elongating in postbranchial
region, becoming long, digitiform in far posterior setigers.
Limbate setae about as long as compound hooks, thick,
marginally serrated. Posterior pectinate setae slender, small;
shafts cylindrical. Blades flat, slightly flaring; marginal teeth
no longer or thicker than other teeth; -10 teeth present. Shafts
of anterior compound hooks distinctly inflated, without distinct
beaks, marginal serrations or internal striations. Appendages
short, tapering with distinct heads. Proximal teeth slightly
shorter than distal teeth, narrowly tapering, directed laterally.
Distal teeth tapering, slender, directed obliquely distally, gently
curved. Hoods asymmetrically bluntly pointed, without
mucros, marginally serrated. Shafts of posterior compound
hooks distinctly inflated, without distinct distal beaks; marginal
serrations and internal striations present. Appendages short,
tapering, chunky with large heads. Proximal teeth larger than
distal teeth, broadly triangular, directed laterally. Distal teeth