Opheliidae (Annelida: Polychaeta) from the western Pacific islands, including five new species
Author
Magalhães, Wagner F.
Author
Rizzo, Alexandra E.
Author
Bailey-Brock, Julie H.
text
Zootaxa
2019
2019-02-13
4555
2
209
235
journal article
27548
10.11646/zootaxa.4555.2.3
2373752d-6333-4f9d-9476-6f2e163a67da
1175-5326
2624293
A7CF86E1-C763-4082-B1C2-9B8B66428142
Genus
Polyophthalmus
Quatrefages, 1850
Type
species
:
Nais picta
Dujardin, 1839
, by subsequent designation.
Diagnosis.
Body elongated, not divided into distinct regions; ventral groove and two lateral grooves present. Segments indistinctly annulated. Prostomium broadly rounded, palpode absent; subdermal eyespots; a pair of large, eversible nuchal organs divided into a ventral and a dorsal region. Branchiae entirely absent. Segmental lateral eyes present between parapodia. Parapodial lobes reduced, notopodial and neuropodial capillaries emerging from body wall. Interparapodial ciliated sensory pits present and a ventral lobe may be present. Noto- and neuropodial lappets absent. Noto- and neuropodial small fascicles of simple capillary chaetae. Pygidium with short anal funnel bearing marginal papillae and a pair of basal papillae.
Remarks.
Hartman (1959)
synonymized thirteen
Polyophthalmus
species with
P. pictus
(
Dujardin, 1839
)
. The author only considered
P. striatus
Kükenthal, 1887
as a valid and distinct species from
P. pictus
.
Michaelsen (1892)
described
P. longisetosus
based on a specimen collected in the pelagic environment with long capillaries on last five segments and it was most likely an epitoke. The species
P. qingdaoensis
Purschke, Ding & Müller, 1995
was recently described and distinguished from
P. pictus
mostly on the basis of the ultrastructure, size, position and number of the segmental eyes (ocelli), and number of anal papillae.
Sene Silva (2007)
, in an unpublished Ph.D. dissertation, examined the
type
material of
P. translucens
Hartman, 1960
and suggested it should be synonymized with
Ophelina abranchiata
Stop-Bowitz, 1948
.
Purschke, Ding & Müller (1995)
described
Polyophthalmus qingdaoensis
based on ultrastructural differences of the segmental eyes and discussed that several
Polyophthalmus
species synonymized with
P. pictus
could actually be valid. Until now, three species are considered as valid:
P. pictus
,
P. qingdaoensis
, and
P. translucens
(
Blake & Maciolek 2016a
)
. A taxonomic revision of the
P. pictus
species complex would be desirable including intra- and interspecific variability but also molecular data, whenever possible. There are very few morphological features and body pigmentation has been the main character used to separate species. However, this feature seems to be variable among populations and the pigmentation can also fade in preserved material. The segmental origin of the lateral eyes and its extent in segments, length of capillaries on anterior and posterior end, number and
types
of capillaries per parapodium, parapodial structures, and number of pygidial papillae should also be comparatively examined.