New species of Dispio Hartman, 1951 and Streblospio Webster, 1879 (Polychaeta, Spionidae) from the coast of the Iberian Peninsula
Author
Delgado-Blas, Víctor Hugo
Author
Díaz-Díaz, Óscar
Author
Viéitez, José M.
text
Zootaxa
2018
2018-04-18
4410
3
525
538
journal article
30236
10.11646/zootaxa.4410.3.6
6bf1a279-6029-4f86-b420-d2e4ca4b35d8
1175-5326
1221840
4C58921D-BD16-4FF3-B10E-3EAE3B5F1481
Streblospio
Webster, 1879
Type species:
Streblospio benedicti
Webster, 1879
.
Diagnosis
. Prostomium oval, fusiform or conical; anteriorly rounded and posteriorly tapered extending to anterior margin of chaetiger 1; 2–4 pairs of eyes or eyes absent; small tentacle or papilla on the dorsum of chaetiger 1 between branchiae; peristomium fused with the first chaetiger, forming short lateral wings enclosing the prostomium; one pair of palps densely ciliated on frontal surface, palp sheaths absent; one pair of branchiae present on chaetiger 1; chaetiger 1 with notopodial postchaetal lamellae absent and capillary notochaetae scarce or absent; entire or bilobed dorsal membranous collar across the dorsum of chaetiger 2; notopodial and neuropodial postchaetal lamellae small, oval, rounded, or flap-like on anterior chaetigers, and digitiform or highly reduced or absent on posterior chaetigers; all notopodial chaetae capillary; neuropodial chaetae include capillaries, multidentate hooded hooks first appearing on chaetigers 6–9, and sabre chaetae beginning on chaetigers 3–7; notopodial hooks absent; pygidium simple or lobed, with or without ventral lappets, cirri absent.
Remarks.
Imajima (1990)
described
Streblospio benedicti japonica
as a new subspecies from
Japan
after comparing his specimens with the description of
S. benedicti
Webster, 1879
.
Imajima (1990)
distinguished
S. benedicti japonica
from
S. benedicti
based on the fact that the former has neuropodial hooks with five pairs of accessory teeth, and sabre chaetae beginning on chaetiger 3, whereas the latter has hooks with 3–4 pairs of accessory teeth, and sabre chaetae beginning on chaetiger 7. In addition,
S. benedicti japonica
has fewer segments (48 vs. 70) than
S. benedicti
, and a pygidium with two lappets, whereas in
S. benedicti
the pygidium is simple or lobed. We propose that these character differences are sufficient to consider the subspecies as a distinct species, and we thus suggest raising the status of
S. benedicti japonica
Imajima, 1990
to full species level as
S. japonica
Imajima, 1990
.
One aspect to consider is the term nuchal papilla. We believe that this term is unsuitable, as when present, this papilla is not in a nuchal position: it is not located in the posterior and inferior region of the prostomium, but rather dorsally on the first chaetiger between the two branchiae.