Revision of Pilargis de Saint-Joseph, 1899 (Annelida, Polychaeta, Pilargidae)
Author
Salazar-Vallejo, Sergio I.
Author
Harris, Leslie H.
text
Journal of Natural History
2006
2006-04-26
40
3 - 4
119
159
http://dx.doi.org/10.1080/00222930600594212
journal article
10.1080/00222930600594212
1464-5262
4669300
Pilargis papillata
Rasmussen, 1973
(
Figure 11
)
Pilargis papillata
Rasmussen 1973
, p 20
–22,
Figure 2
.
Type material
Northeastern Atlantic Ocean
:
holotype
(ZMUB-53527),
Fensfjorden NE
for
Gardsenflu
(60
°
499N, 5
°
039420E),
Norway
,
412 m
, coll.
K. Rasmussen. Complete
animal; two (not three)
paratypes
(ZMUB-53528),
Fensfjorden, NE
for
Gardsenflu
,
Norway
, 580–
412 m
, coll. and id.
K. Rasmussen
(dried out; anterior fragment
14.5 mm
long, 1.0 mm wide, 73 setigers; posterior fragment with eight setigers)
.
Redescription
Holotype
(ZMUB-53527) complete, twisted over itself, making difficult any measurement without further damaging it. It was described as
20 mm
long (it is
5.7 mm
long), 1.0 mm wide (setiger 15), 80 setigers and a regenerating posterior end with eight or nine asetigers; it has 26 setigers and a regenerating portion with two inmature setigers and three preanal asetigers. It is now colorless but the posterior brain lobes are dark (occupy first setiger and slightly invade the second one). Body flat, densely covered by verrucae dorsally, verrucae abundant over tentacular and dorsal cirri (
Figure 11A
). Ventrally verrucae restricted to parapodial bases, smaller, leaving a smooth midventral wide area limited by two longitudinal muscle bands. Left setigers 7–10 are folded dorsally (because of body compression in the vial).
Prostomium completely fused dorsally to peristomium; palps biarticulate, palpostyles central, directed ventrally. Lateral antennae wide, densely covered with verrucae, placed anteriorly, slightly surpass prostomial anterior margin (
Figure 11B, C
). Tentacular cirri cirriform, directed anteriorly, dorsal ones slightly larger than the ventral.
First setiger with dorsal cirri globose, thin, acuminate, slightly longer than dorsal tentacular cirri, slightly shorter than dorsal cirri of second setiger. Anterior
parapodia
with fusiform cirri with verrrucae; dorsal cirri twice as long as ventral cirri, much thicker (
Figure 11E
). Posterior
parapodia
with dorsal cirri foliose, larger than setal lobe, separated in cirrophore and cirrostyles (
Figure 11F
). Cirrophore massive with dense cover of large verrucae, with an anterior small glandular area; cirrostyles digitate with smaller verrucae. Ventral cirri smooth placed basally to the setal lobe and shorter than it. Neurosetae mostly complete; despite adsorpted materials, they are limbates with limbus thin, smooth, distally entire (in
paratype
, most setae broken, some appear distally bidentate).
Posterior end with pygidium in regeneration; damaged (
Figure 11D
); two setigers and three preanal asetigers. Pygidium as an inverted truncate cone, two ventrolateral anal cirri well developed, with many verrucae.
Paratypes
with enteric diverticula dark, clearly seen from setiger 15; few eggs can be seen from about setiger 50. Posterior fragment shows them too.
Discussion
The
holotype
differs in several regards to the original description, besides the difference in size. The original illustration included a ventral view, which was indicated as a dorsal view. The posterior brain lobes are dark, there are two other lateral smaller dark glands projecting towards the posterolateral corners of the tentacular segment, and the pigmented glandular area in posterior cirrophores has faded slightly. The dorsal cirri are larger in median setigers; the second dorsal cirri is not shorter than the first dorsal cirri. The neurosetae are distally entire, not bidentate, and have a thin, smooth blade.
This species belongs to the group with abundant dispersed verrucae over the back and parapodial lobes.
Pilargis papillata
is closely allied to
P. modesta
and
P. rozbaczyloi
n. sp.
, but differs from them by having the first dorsal cirri smaller than the following ones rather than larger, and fusiform verrucose dorsal cirri, contrasting with digitate verrucose cirri in
P. rozbaczyloi
n. sp.
, and smooth fusiform cirri in
P. modesta
.
Distribution
Restricted to the
type
locality in
Southwestern
Norway
in depths of over
400 m
.