| 1a |
Mouth separate from the proboscis
pore, and both openings located on the ventral
side of the head posterior
to the brain; proboscis
without stylets (Class Anopla) |
2 |
| 1b |
Mouth united with the proboscis
pore, the single opening located at the anterior tip of the head (photo);
proboscis
armed with a stylet (except
in the leechlike genus Malacobdella)(Class Enopla) |
23 |
| 2a |
Head without cephalic
slits (Order Palaeonemertea and one species [Baseodiscus princeps]
of the order Heteronemertea) |
3 |
| 2b |
Head with cephalic
slits (Order Heteronemertea) |
10 |
| 3a |
With conspicuous nematocyst-like
structures in the epidermis; length not exceeding 1 cm; interstitial |
Cephalothrix pacifica |
| 3b |
Without nematocyst-like
structures in the epidermis; length usually much greater than 1 cm; not
interstitial |
4 |
| 4a |
Body either with conspicuous white rings or longitudinal lines, or
both |
5 |
| 4b |
Body color more or less homogeneous, with neither rings nor longitudinal
lines |
7 |
| 5a |
General color deep red, interrupted by white rings that are spaced
at intervals about equal to the width of the body; without longitudinal
lines; anterior margin
of head white |
Tubulanus albocinctus |
| 5b |
General color brownish, interrupted by white rings; with white longitudinal
lines; anterior margin
of head not white |
6 |
| 6a |
General color orange-brown to chocolate; with 5 or 6 longitudinal lines
consisting of densely packed white dots (besides a mid-dorsal
line, there are 2 lines on both the right and left sides of the body,
and sometimes a faint mid-ventral
line is present); white rings evenly spaced |
Tubulanus sexlineatus |
| 6b |
General color dark brown throughout most of the body, although the
posterior region is slightly lighter; with 3 white longitudinal lines (a
continuous mid-dorsal line and 2 lateral lines that are broken into dashes
anteriorly); white rings
not evenly spaced (the anteriormost
band of white pigment lies just behind the level of the mouth and forms
a V on the ventral surface) |
Tubulanus capistratus |
| 7a |
General color cream, not more than 50 cm long |
8 |
| 7b |
General color ochre,
orange, or reddish; length commonly exceeding 1 m, and sometimes attaining
3 m |
9 |
| 8a |
Generally 10-30 cm long and flattened posteriorly; head milky white;
intestinal diverticula conspicuous (gravid
females pinkish in the intestinal region; males that contain sperm are
light orange in this part of the body) |
Carinoma mutabilis |
| 8b |
Less than 3 cm long and very slender; head not milky white; intestinal
diverticula not conspicuous (gravid
females may have mid-dorsal and mid-ventral stripes between the cream-colored
ovaries that are in the lateral
portions of the body) |
Tubulanus pellucidus |
| 9a |
Head without eyespots and without a pair of anteroventral
grooves; color uniformly orange or reddish |
Tubulanus polymorphus
Renier, 1804 |
| 9b |
Head with numerous eyespots and with a pair of oblique grooves on the
anteroventral surface
(these grooves are inconspicuous); color deep ochre
to brownish |
Baseodiscus princeps |
| 10a |
Caudal cirrus
absent (Note: may just be missing); length of proboscis
sheath variable (it may be much shorter than the body or nearly as long
as the body) |
14 |
| 10b |
Caudal cirrus
present (it may merely be missing, however, if the posterior
end has been damaged);
proboscis
sheath usually as long as the body |
11 |
| 11a |
|
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| 11b |
|
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| 12a |
|
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| 12b |
|
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| 13a |
|
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| 13b |
|
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| 14a |
Body relatively soft and slender, not markedly flattened or otherwise
adapted for swimming; length usually less than 50 cm |
15 |
| 14b |
Body firm and markedly flattened posteriorly, adapted for swimming;
length sometimes more than 50 cm |
17 |
| 15a |
Body with distinct transverse
rings of a contrasting color |
16 |
| 15b |
Body color homogeneous (creamy tan to pale salmon) and lacking transverse
rings of a contrasting color (tip of head white) |
Micrura alaskensis |
| 16a |
Dorsal surface mostly
dark brown or purple, but with regularly spaced, transverse
white lines that divide the dark color into rectangles (ventral
surface ivory white); dorsal
surface of head with a conspicuous orange triangle. |
Micrura verrilli |
| 16b |
General color deep chestnut or some shade of brown, interrupted by
irregularly spaced white rings; anterior
tip and sides of head with a white border (the body fragments readily) |
Micrura wilsoni |
| 17a |
Much of the head whitish and thus distinctly demarcated from the rest
of the body |
18 |
| 17b |
Head not white and not distinctly different from the rest of the body
(the lateral margins of
the head may be lighter however) |
19 |
| 18a |
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| 18b |
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| 19a |
Neck region (immediately behind the head) slightly narrowed and thus
separating the head from the rest of the body; cephalic
slits large in proportion to the length of the body, which is usually
less than 20 cm. |
20 |
| 19b |
Neck region not obviously narrowed (head not distinct from the rest
of the body); cephalic
slits small in proportion to the length of the body, which is usually
greater than 20 cm |
21 |
| 20a |
Color generally some shade of dull red to grayish rose, but sometimes
greening brown (extremely fragile and likely to b reak into small pieces) |
Cerebratulus californiensis |
| 20b |
Color dark brown to purple on the dorsal
surface, slightly lighter ventrally
and along the margins of the head. |
Cerebratulus longiceps |
| 21a |
|
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| 21b |
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| 22a |
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| 22b |
|
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| 23a |
Body leechlike, with a muscular attachment disk at the posterior end;
proboscis
without a stylet; commensal
in the mantle cavity of bivalve molluscs (Siliqua
patula, Macoma
nasuta, M. secta, and probably others) |
Malacobdella sp |
| 23b |
Body not leechlike, and without a muscular attachment disk at the posterior
end; proboscis with a
stylet;
not commensal in the mantle cavity of bivalve molluscs |
24 |
| 24a |
Semi-terrestrial, generally found under rocks and driftwood at the
edges of bays and saltmarshes, at a level reached only by the highest tides
(dorsal surface grayish green or bluish green, with a poorly defined, darker
longitudinal stripe; with 4 clusters of eyespots on the head, the anterior
clusters with about 40 eyespots each, the posterior clusters with about
20 eyespots; length up to 25 cm) |
Pantinonemertes californiensis |
| 24b |
Truly marine, not restricted to a level reached only by the highest
tides |
25 |
| 25a |
Stylet shaft with helical
grooves and ridges |
26 |
| 25b |
Stylet shaft smooth |
29 |
| 26a |
With a conspicuous statocyst dorsal to each half of the brain; length
usually less than 5 mm; interstitial |
Ototyphlonemertes americana |
| 26b |
Statocysts absent; length much greater than 5 mm, not interstitial |
27 |
| 27a |
Proboscis sheath
less than 1/5 the length of the body; proximal portion of stylet
discoidal and inconspicuous; length up to 1 m (fairly stout and conspicuously
flattened; color typically tan, with light brown specks, or slightly purplish;
dorsal surface darker than the ventral surface) |
Emplectonema purpuratum |
| 27b |
Proboscis sheath
more than 1/5 the length of the body; proximal piece of stylet
prominent; length not often more than 30 cm |
28 |
| 28a |
Dorsal surface brown to purple-brown, ventral surface creamy yellow;
typically with 2 or 3 sacs of reserve stylets
(an average of 4 stylets
in each sac) |
Paranemertes peregrina |
| 28b |
Color uniformly flesh to pale orange; typically with 4-6 sacs of reserve
stylets
(about 6 stylets in each
sac) |
Paranemertes sanjuanensis |
| 29a |
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| 29b |
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| 30a |
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| 30b |
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| 31a |
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| 31b |
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| 32a |
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| 32b |
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| 33a |
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| 33b |
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| 34a |
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| 34b |
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| 35a |
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| 35b |
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