A Review of the Genus Eunice - Smithsonian Institution Libraries

NUMBER 523 311
184. Eunice stigmatura (Verrill, 1900)
FIGURES 106,22,23, 46, 48
Ltodice stigmatura Verrill, 1900:641-643.—Treadwell, 1921:20-22, figs.
31-40, pi. 1: figs. 10-13.
Eunice villata.—Hartman, 1942:9 [in part, nol Nereis vittata Chiaje, 1829].
MATERIAL EXAMINED.—TWO syntypes, YPM 1232, Bermuda
Islands, low water, 1898, A.E. Verrill; YPM 1041 and
2095, Bermuda Islands, low water, 1898, coll. A.E. Verrill, 3
specimens; YPM 2094, Castle Harbor, Bermuda Islands, 1898,
coll. A.E. Verrill, 3 specimens; YPM 12%, Bermuda Islands,
low water, 1901, coll. A.E. Verrill.
DESCRIPTION.—Large syntype incomplete mature female
with 116 setigers; length 42 mm; maximal width 2 mm; length
through setiger 10, 4 mm. One specimen from YPM 2095
(presumably part of original material, but not designated as
type) complete with 151 setigers, length 60 mm.
Prostomium (Figure 106d) distinctly shorter and narrower
than peristomium, less than 1 /2 as deep as peristomium.
Prostomial lobes frontally rounded, dorsally inflated; median
sulcus shallow. Eyes hidden beneath peristomial fold, posterior
to bases of A-I. Antennae in a horseshoe, evenly spaced, similar
in thickness. Ceratophores ring-shaped in all antennae, without
articulations. Ceratostyles slender and digitiform, with up to 15
short, cylindrical articulations in A-I 11 of short syntype; A-I 11
lost in large syntype. A-I to setiger 1, A-I I to setiger 8; A-I 11 (in
short syntype) to setiger 10. Peristomium cylindrical, with
somewhat expanded lower lip. Separation between rings very
distinct on all sides; anterior ring 2 h of total peristomial length.
Peristomial cirri to tip of prostomium, slender and digitiform,
with 8 to 9 short, cylindrical articulations.
Maxillary formula of specimen from YPM 2095 1+1, 6+6,
8+0, 6+8, and 1+1. Max III long, located behind left Max II.
Max VI absent. Jaws poorly sclerotinized.
Branchiae (Figure 106a) present, pectinate, about as long as
notopodial cirri, not reduced in mid-body region, erect.
Branchiae from setiger 3 to setiger 110. Branchiae on setigers
70-80 very short and easily overlooked (Figure 106e);
filaments increase in length in last 10-15 branchiated setigers.
Branchiae present to near posterior end, more than 65% of total
number of setigers. First 4 and roughly last 40 branchiae single
filaments; maximum 5 filaments at about setiger 15. Branchial
stems short, slender. Most filaments long and slender.
Anterior neuropodial acicular lobes obliquely rounded with
aciculae emerging near upper edge; median and posterior
acicular lobes symmetrically rounded with aciculae emerging
above distal point of neuropodia. All pre- and postsetal lobes
low, transverse folds. First 6 ventral cirri long and tapering.
Ventral cirri basally somewhat inflated from about setiger 7
through setiger 45. Inflated bases ovate; narrow tips tapering.
Posterior ventral cirri digitiform with rounded tips, increasingly
prominent posteriorly. All notopodial cirri prominent, increasing
in length from setiger 1 through setiger 7-8, thereafter
decreasing slowly in length, but distinctly longer than
branchiae in all branchiated setigers. Anterior notopodial cirri
with up to 13 distinct articulations; articulations become less
distinct and fewer posteriorly; last 25 notopodial cirri without
obvious articulations.
Limbate setae slender, marginally finely serrated. Pectinate
setae (Figure 106fJc) very narrow, tapering, flat. One marginal
tooth about twice as thick and long as other teeth; 5-6 teeth
present in pectinate setae from all parts of body. Shafts of
compound falcigers (Figure 106c,g) distally inflated, marginally
finely serrated; distinct beak present. Appendages decreasing
in length from anterior to posterior setigers, bidentate.
Anterior appendages with proximal teeth smaller than distal
teeth, short, tapering, blunt-tipped, directed distally. Distal
teeth very slender, directed obliquely distally. Posterior
appendages with proximal teeth about as long as distal teeth,
triangular, directed basally. Distal teeth tapering, directed
obliquely distally. All guards asymmetrically bluntly pointed,
becoming distinctly more symmetrical in posterior setigers,
marginally serrated; mucros absent. Pseudocompound falcigers
and compound spinigers absent. Aciculae (Figure 106b) paired,
yellow, distally abruptly tapering. Superior aciculae always
thinner than inferior aciculae; cross-sections round. Separation
between core and sheath indistinct in both aciculae and
subacicular hooks. Subacicular hooks (Figure 106h,i, j) yellow,
bi- or tridentate. Hooks first present from setigers 29 and 31 in
syntypes (from setigers 27-35 in other material), present in all
setigers thereafter, always single (except for replacements). All
hooks with large, laterally directed proximal fang. Distal ends
with thick; broad shafts crowned by either 2 fangs or terminated
bluntly as a single, thick, angular fang. Tertiary fang small in
most specimens. Hooks not obviously worn; newly forming
hooks with 2 or 3 distinct teeth present.
UNKNOWN MORPHOLOGICAL FEATURES.—Pygidium and
anal cirri.
EXPECTED STATES OF UNKNOWN MORPHOLOGICAL FEA-
TURES.—None.
CHARACTERS USED IN PREPARATION OF KEY NOT
SCORED.—Inappropriate Characters: 56, 58, 59. Unknown
Characters: 1,2,4,6.
ASSUMED STATES FOR PURPOSE OF PREPARING KEY.—
None.
REMARKS.—Specimens that are not listed as types above are
assumed to be part of the original material.
Treadwell (1921) gave no evidence of having seen the types,
but did examine material from the type locality.
Eunice stigmatura has been considered synonymous with E.
vittata, but the branchial distribution is different in that the
former has branchiae continued to near the posterior end; the
latter has branchiae terminating well before the posterior end.
The two syntypes have exclusively single, thick, truncate distal
teeth, rather than paired fangs in the subacicular hooks; the
other specimens of the original material have three teeth. Only
a single specimen, from YPM 2094, was observed to have
some subacicular hooks with single large teeth and others with
three fangs.