A Review of the Genus Eunice - Smithsonian Institution Libraries

226 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY
TABLE 9.—Variable and invariable features in the type lot of Eunice mucronata (N = number of individuals
examined; SD = standard deviation; measurements in mm).
VARIABLE FEATURES
No. of setigers
Total length
Maximum width
Max. width at setiger no.
Length through 10
Width at 10
Length of A-I
Length of A-II
Length of A-III
Teeth in left MxII
Teeth in right Mx II
Teeth in Mx III
Teeth in left Mx IV
Teeth in right Mx IV
Last bronchia on setiger no.
Max. no. of branchial filaments
No. of anterior setigers with single filaments
No. of posterior setigers with single filaments
No. of anterior setigers with tapering ventral cirri
Ventral cirri inflated through setiger no.
No. of aciculae
Subacicular hooks first present from setiger no.
No. of subacicular hooks present
N
6
6
14
14
14
14
14
13
6
7
7
7
7
7
13
14
14
13
14
13
14
14
14
Max.
116
59
4
25
8
3.5
2
12
15
9
10
12
9
11
34
15
3
1
5
40
3
22
2
Min.
95
36
2
15
6
1.75
0
4
7
7
8
8
6
8
29
11
2
0
3
31
2
18
1
Mean
SD
106 8.05
48.17 9.26
2.82 0.5
21.07 4.87
6.71 0.64
2.46 0.44
1.21 0.58
8.15 2.7
10.67 :1.14
8.43 0.79
8.29 ().76
9.86
8.29
10.14
32
12.5
2.93
.35
.11
.07
.63
.34
().27
0.15 ( ).3K
4.86 ( ).53
36.23
2.07
2.59
()27
20.07
1.14
1.07
()36
INVARIABLE FEATURES
Antennal articulations
Peristomial cirri reach
Peristomial cirral articulations
No. of teeth in Mx V
Branchiae first present from setiger no.
Branchiae
Articulations of notopodial cirri
Pectinate setae
No. of teeth in pectinate setae
Shafts of compound falcigers
Acicular shape
Core-sheath construction
Subacicular hooks
Dorsal edge of pygidium (N=6)
Anal cirri (N=6)
N=14
absent
middle or front of prostomium
absent
1
3
outreach notopodial cirri
absent
slightly flaring; flat
10
slightly inflated
tapering
distinct
in every segment after start
crenulated
long; without articulations
(Figure 75d) gently flared, flat. One marginal tooth longer than
other teeth; -10 teeth present Shafts of compound falcigers
(Figure 75e) gently inflated, marginally finely serrated.
Appendages extremely long, slender, tapering to blunt, gently
curved tips, bidentate. Proximal teeth low, triangular thickenings
near distal ends of appendages. Guards extremely long,
tapering to fine mucronate tips. Pseudocompound falcigers and
compound spinigers absent. Aciculae paired in most parapodia,
yellow, slender, tapering, straight or gently curved; crosssections
round. Separation between core and sheath indistinct
in both aciculae and subacicular hooks. Subacicular hooks
(Figure 75b) yellow, tridentate. Hooks first present from setiger
22 (18-21 in other syntypes), present in all setigers thereafter,
always single (except for replacements). Hooks distally curved.
Fangs decreasing evenly in size from large main fangs to small
tertiary fangs.
UNKNOWN MORPHOLOGICAL FEATURES.—Relationship between
Mx III and left Mx IV; pygidium and anal cirri.
EXPECTED STATES OF UNKNOWN MORPHOLOGICAL FEA-
TURES.—Mx III long and located behind left Mx II.
CHARACTERS USED IN PREPARATION OF KEY NOT
SCORED—Inappropriate Characters: 22, 56, 58, 59. Unknown
Characters: 6,42.
ASSUMED STATES FOR PURPOSE OF PREPARING KEY.—
None.
REMARKS.—Eunice mucronata is listed with similar species
in Tables 41 and 45. It is the only species in Table 45 with
peristomial cirri clearly projecting beyond the prostomium. It is
also characterized by the very long antennae and the extremely
long, pointed guards in the compound falcigers.