Pilargidae (Annelida: Phyllodocida) from coastal and deep waters of the Southwestern Atlantic, with descriptions of two new species
Author
Ribeiro, Rannyele Passos
0000-0002-0304-7053
Departamento de Biología, Universidad Autónoma de Madrid, 28049, Madrid, Spain.
Author
Barbosa, Aline Da Cruz
0000-0002-6219-1557
Programa de Pós-Graduação em Ciências Ambientais e Conservação, Instituto de Biodiversidade e Sustentabilidade, Universidade Federal do Rio de Janeiro, 27965 - 045, Macaé, RJ, Brazil.
Author
Freitas, Roberta
0000-0002-2178-791X
Departamento de Zoologia, Universidade Federal do Rio de Janeiro, 21941 - 599, Rio de Janeiro, RJ, Brazil. & freitas. r. roberta @ gmail. com; https: // orcid. org / 0000 - 0002 - 0816 - 761 X
freitas.r.roberta@gmail.com
Author
Zanol, Joana
0000-0002-9464-1938
Museu Nacional, Universidade Federal do Rio de Janeiro, 20940 - 040, Rio de Janeiro, RJ, Brazil.
Author
Glasby, Christopher J.
0000-0002-0816-761X
Museum and Art Gallery of the Northern Territory, PO Box 4646, Darwin NT 0801, Australia.
Author
Ruta, Christine
0000-0001-6412-6751
Departamento de Zoologia, Universidade Federal do Rio de Janeiro, 21941 - 599, Rio de Janeiro, RJ, Brazil. & christineruta @ gmail. com; https: // orcid. org / 0000 - 0001 - 6412 - 6751
christineruta@gmail.com
text
Zootaxa
2020
2020-11-12
4878
1
56
76
journal article
7928
10.11646/zootaxa.4878.1.2
ffe57499-723a-4ade-a574-215e0e1f8742
1175-5326
4574027
29DB126D-4751-433B-89BC-EFDD421368F7
Glyphohesione campensis
sp. nov.
Figure 6
A–G
urn:lsid:zoobank.org:act:
4E065FE1-CDC0-4D3F-87A3-2CE72C3259BC
Material examined.
BRAZIL
:
Campos Basin
:
Holotype
:
21º13’38.308”S
,
40º14’57.803”W
,
417 m
, one specimen,
5.ii.2009
(MNRJP-002724).
Paratypes
:
21º40’23.730”S
,
40º58’23.765”W
,
18 m
, one specimen,
19.vii.2009
(MNRJP-002725);
22º56’2.563”S
,
41º53’51.338”W
,
48 m
, one specimen,
28.ii.2009
(MNRJP-002726);
22º59’1.044”S
,
40º48’27.955”W
,
380.6 m
, one specimen,
1.ii.2009
(MNRJP-002727);
22º19’2.381”S
,
40º5’27.062”W
,
383.8 m
, one specimen,
31.i.2009
(MNRJP-002728);
21º56’11.947”S
,
39º57’45.285”W
,
720 m
, one specimen,
4.ii.2009
(MNRJP-002729);
21º40’16.833”S
,
39º58’6.138”W
,
1,005.8 m
, three specimens,
08.ii.2009
(MNRJP-002730).
Diagnosis.
Notopodial spine from fifth chaetiger. Dorsal cirri of anterior chaetigers about half the length of body width. Neurochaetae finely serrated with entire and straight tips, up to eight per parapodium.
Description.
Fixed specimens whitish over most of body, orange-coloured on anterior region. The following description is based on the
holotype
:
3 mm
long,
0.30 mm
width (at widest point, including parapodia) and 24 chaetigers. Body dorsoventrally flattened; first five or six anterior segments distinctly wider and inflated than more posterior (
Fig. 6A
). Body surface smooth, no papillae. Prostomium bilobed, slightly wider than long; three long and slender antennae, median antenna posterior to lateral antennae; eyes absent (
Fig. 6B
). Two biarticulated palps, palpophore large, and palpostyle about one-third shorter than lateral antennae. Proboscis cylindrical, without papillae. Peristomium indistinct from prostomium, two pairs of tentacular cirri twice longer than lateral antennae; dorsal tentacular cirri 1.2x longer than ventral ones (
Fig. 6D, E
). Parapodia sub-biramous.
FIGURE 6.
Glyphohesione campensis
sp. nov.
A. Whole body. B. Anterior body showing prostomium, peristomium and first chaetigers. C. Parapodium from midbody. D–G. SEM images. D. Anterior body showing peristomium and first chaetigers, specimen was damaged during fixation procedures. E. Detail of tentacular cirri, left side. F. Parapodial detail showing notopodial spine, left parapodium of chaetiger 10. G. Serrated neurochaetae from midbody parapodia, chaetiger 10. All pictures in dorsal view. Abbreviations. Dc: dorsal cirrus, La: lateral antenna, Ma: median antenna, Ns: notopodial spines, Pb: proboscis, Pt: prostomium, Py: pygidium, Tdc: tentacular dorsal cirrus. Scale bars: 200 µm (A), 100 µm (B–D), 50 µm (E, F), 10 µm (G).
Dorsal and ventral parapodial cirri elongated and slender. Dorsal cirri about half the length of anterior body width. Dorsal cirri on first chaetiger 2.5x longer than following and 1.3x longer than dorsal tentacular cirri (
Fig. 6D
). Ventral cirri shorter than dorsal cirri. Notopodial lobe reduced. Notopodial spines ventral to dorsal cirri, one per notopodium, present from fifth to last chaetiger (
Fig. 6C, F
). Neuropodial lobes well developed and conical, with eight finely serrated neurochaetae with entire and straight tips (
Fig. 6G
). Pygidium slender, without papillae and with two elongated cirri (
Fig. 6A
).
Distribution.
Atlantic Ocean—Brazil, Campos Basin, specimens examined in this study.
Remarks.
This species is assigned to the genus
Glyphohesione
due to the presence of simple chaetae, a straight notopodial spine located ventral to the dorsal cirri, elongated palpostyles, and the position of lateral and median antennae. There are currently three described species in the genus:
G. klatti
(
Friedrich 1950
)
,
type
species of the genus described from the North Sea,
Germany
;
G. longicirrata
Licher, 1994
, from Gulf of Mexico,
USA
and
G. nicoyensis
Dean, 1998
, from Gulf of Nicoya,
Costa Rica
. However, the new species described here differs in the first appearance of notopodial spines, relative length of dorsal cirri in relation to body width and the number of neurochaetae. The notopodial spines of
Glyphohesione campensis
sp. nov.
begin on the fifth chaetiger, while in
G. klatti
they emerge from chaetigers 5–8, in
G. nicoyensis
they emerge from chaetigers 7–10, and in
G. longicirrata
between chaetigers 10–15. Also, the new species differs in the relative length of dorsal cirri in relation to the anterior body width: in
G. klatti
and
G. nicoyensis
cirri length is one-quarter of the body width, in
G
.
longicirrata
dorsal cirri are as long as the body width; and in
Glyphohesione campensis
sp. nov.
they are half of the body width. Regarding the variation in structure and number of neurochaetae,
G. klatti
has up to 25 finely serrated chaetae with entire and curved tips;
G. longicirrata
, up to 14 finely serrated chaetae with minutely bifid tips;
G. nicoyensis
, up to 18 finely serrated chaetae with entire and curved tips; and
Glyphohesione campensis
sp. nov.
, up to 8 finely serrated chaetae with entire and straight tips (
Table 1
). Additionally,
Glyphohesione campensis
sp. nov.
differs from
G. nicoyensis
in lacking eyespots (
Table 1
).
Etymology.
Named after the
type
locality because the species presents a wide distribution along the Campos Basin.