Amazing Diversity of Nothria (Annelida, Onuphidae) in the Australian Deep Sea
Author
Paxton, Hannelore
School of Natural Sciences, Macquarie University, Sydney NSW 2109, Australia & Australian Museum Research Institute, Australian Museum, 1 William Street, Sydney NSW 2010, Australia
Author
Budaeva, Nataliya
Department of Natural History, University Museum of Bergen, University of Bergen, Allégaten 41 5007, Bergen, Norway
Author
Gunton, Laetitia M.
Australian Museum Research Institute, Australian Museum, 1 William Street, Sydney NSW 2010, Australia
text
Records of the Australian Museum
2023
Rec. Aust. Mus.
2023-05-17
75
3
215
247
http://dx.doi.org/10.3853/j.2201-4349.75.2023.1802
journal article
10.3853/j.2201-4349.75.2023.1802
2201-4349
10414092
547C922B-640C-4C2A-AE42-9C464AE54BF9
Nothria josae
sp. nov.
urn:lsid:zoobank.org:act:
D8BEF1C4-7863-4808-8245-609D9DBABC7A
Figs 1
,
12–14
,
Tables 2
, S
1
Nothria
sp. nov.
3.—Gunton
et al.,
2021:76, fig
16F.
Holotype
. Australian Museum (
AM
) W.51343,
IN2017
_
V03
_100;
9 Jun 2017
;
Australia
,
New South Wales
,
Byron Bay
, 28.05–
28.10°S
154.08°E
;
999–1013 m
depth
.
Paratypes
(5):
AM
W.49935,
IN2017
_
V03
_100 (1);
AM
W.49937,
IN2017
_
V03
_100 (1);
AM
W.51344,
IN2017
_
V03
_100 (1);
AM
W.51345,
IN2017
_
V03
_100 (1);
AM
W.51445,
IN2017
_
V03
_121 (1 mounted on
SEM
pin).
Other material examined
(31).
AM
W.49936,
IN
2017_
V
03_100 (25);
AM
W.49934,
IN
2017_
V
03_121 (2);
AM
Figure 13
.
Nothria josae
sp. nov.
Line drawings of AM W.49934. (
A
) slender bidentate simple hook from chaetiger 1; (
B
) very slender bidentate pseudocompound hook from same; (
C
) very slender bidentate pseudocompound hook from chaetiger 2; (
D
) bidentate serrated compound hook from chaetiger 3; (
E
) mandibles; (
F
) maxillae.
W.51449,
IN
2017_
V
03_121 (
3 in
tubes);
AM
W.53850.
IN
2017_
V
03_121 (1).
Diagnosis
. Large posterior eyes present; antennae extending to chaetiger 7–11; branchiae short digitate filaments, from chaetiger 11–13; 3 first chaetigers with anterior hooks: slender, bidentate simple and pseudocompound hooks on chaetiger 1; slender bidentate pseudocompound hooks on chaetiger 2 and very slender bidentate pseudocompound to compound hooks on chaetiger 3; pectinate and limbate chaetae from chaetiger 3; subacicular hooks from chaetiger 9–12.
Description
. All specimens lacking posterior ends. Length of
holotype
5.5 mm
for 13 chaetigers, width
1.5 mm
;
paratypes
4.5–15 mm
(12–30 chaetigers) long, 1.5–2.0 mm wide. Non-type material ranging from 1.0–
1.8 mm
in width. Alcohol-stored specimens overall whitish to cream-coloured. Few specimens with pale brown median spot on prostomium, pale brown splotches on first parapodia and on ventral upper and lower lips;
holotype
and most other specimens without any pigmentation. Subdermal brown pigment or blood in jaw region, sometimes visible through epidermis dorsally. Prostomium subtriangular, wider than long, with 2 closely spaced ovoid frontal lips (
Fig. 12A,B
). Palpo- and antennophores with 2–3 proximal rings and longer distal ring (
Fig. 12A
). Palpostyles tapering, extending to chaetiger 1, antennostyles tapering gradually, lateral antennostyles extending to chaetiger 9 (7–9), median antennostyle noticeably thicker than laterals (
Fig. 12A
), extending to chaetiger 11 (9–10). Nuchal grooves straight, with small middorsal separation. Large posterior pair of eyes at bases of lateral antennae, faded in
holotype
but darkly pigmented in
paratypes
and other specimens. Ventral upper lips rounded, lower lips subtriangular, neither with median section (
Fig. 12B
). Peristomium short, peristomial cirri inserted subdistally on peristomium, about twice as long as peristomium (
Fig. 12A
).
Figure 14
.
Nothria josae
sp. nov.
(
A
) photograph of tube AM W.51449; (
B
) map of distribution; red dot represents type locality, green dot other site of collection.
First chaetiger enlarged, about twice as long as peristomium, chaetiger 2 much shorter, chaetiger 3 similar in length to following ones. Anterior three pairs of parapodia modified (
Fig. 12A,B
). First pair greatly enlarged, directed forward, extending well beyond prostomium, with large auricular prechaetal lobes, subulate postchaetal lobes, dorsal and ventral cirri (
Fig. 12A,B
). Parapodia 2 similar but smaller, with smaller prechaetal, digitate postchaetal lobes and subulate ventral cirri (
Fig. 12A,B
). Parapodia 3 only slightly larger than subsequent ones (
Fig. 12A,B
), directed anterolaterally, with tongue-like prechaetal lobes (
Fig. 12C
). From chaetiger 4 onwards parapodial structures becoming more uniform; prechaetal lobes continued into posterior region, last postchaetal lobes on chaetiger 14 (13–16). Dorsal cirri long and slender to chaetiger 10–12, thereafter becoming gradually shorter, by chaetiger 30 reduced to tiny stumps. Ventral cirri transitional on chaetiger 3, replaced by glandular pads from chaetiger 4 (
Fig. 12B
). Branchiae beginning on chaetiger 11 (11–13, most often 12) as little stump, becoming short digitate filament (
Fig. 12D
) by chaetiger 15–17, continuing as tiny stump to end of incomplete specimens.
First pair of parapodia with 2 bidentate almost slender simple hooded hooks (
Figs 12E
,
13A
) and 1 slender bidentate pseudocompound (
Fig. 13B
) hook. Parapodia 2 with 3 slender simple to pseudocompound (
Fig. 13C
) bidentate hooks. Parapodia 3 (
Fig. 12C
) with 2–4 upper limbate chaetae, about 20–30 scoop-shaped pectinate chaetae with 18–20 teeth, 2–3 very slender bidentate pseudocompound to compound hooks with serrated upper shafts and appendages (
Fig. 13D
). Following parapodia (
Fig. 12D
) with 5–6 upper limbate, several pectinate and lower limbate chaetae; subacicular hook present singly from chaetiger 12 (9–12) and as pairs from chaetiger 15 (12–16). Pygidium unknown.
Mandibles (
Fig. 13E
) highly calcified, white, except for darkly sclerotized protomandibles; shafts long and slender, cutting plates high with pronounced median and large distal tooth. Maxillae (
Fig. 13F
) overall beige coloured, fangs and teeth brown, ligaments and attachment lamellae more sclerotized, appearing dark brown. Maxillary formula (based on
3 paratypes
): MI = 1+1;
MII
= 6–7 + 7–8 (left most distal tooth fang-like); MIII = 7–8 + 0; MIV = 6–7 + 8–10; MV = 1+1. Ratio of mandibles/maxillae = 1.2. Flattened tube, lining transparent, covered on outside with different sized shell fragments (some much larger than diameter of tube), lateral spaces between shells filled in with small particles (
Fig. 14A
).
Remarks
. Below we describe a sister species to
N. josae
sp. nov.
, where morphological similarities and differences between the two species will be discussed.
Etymology
.
Nothria josae
sp. nov.
is named for Josie Paxton, granddaughter of the first author.
Distribution
. The new species was collected from the Coral Sea Marine Park,
Queensland
and off Byron Bay,
New South Wales
, in
999–1013 m
and the Coral Sea Marine Park in
1013–1093 m
depth (
Fig. 14B
).