New genera and species from the Equatorial Pacific provide phylogenetic insights into deep-sea Polynoidae (Annelida)
Author
Bonifácio, Paulo
Author
Menot, Lénaïck
text
Zoological Journal of the Linnean Society
2019
185
555
635
journal article
0024-4082
74C07292-2BD6-4E3E-B68D-B144B81BBD83
HODOR HODOR
SP. NOV.
(
FIG. 12A–H; TABLES
1, 2)
Type material:
Holotype
, MNHN-IA-TYPE 1825 (
IFR655-2
-
1
), complete, length
11.35 mm
, width
1.68 mm
, 24 segments (including tentacular segment),
Equatorial
Eastern Pacific Ocean
,
Clarion-Clipperton Fracture Zone
,
APEI#3
, station 192, collected
21 April 2015
, epibenthic sledge epi-net, start
18°44.807′N
,
128°21.874′W
, end
18°45.338′N
,
128°20.418′W
, 4821–
4820 m
depth,
2799 m
trawling distance.
Description (based on
holotype
):
Holotype
complete,
11.35 mm
long and
1.68 mm
wide for 24 segments (including tentacular segment), dorsoventrally flattened, posteriorly tapering; colour of live animal not known; ethanol-preserved specimen pale white (
Fig. 12A
).
Prostomium bilobed, about as long as wide, lobes subtriangular, poorly developed, anteriorly tapering into blunt peaks, extending until superior lip; frontal filaments absent; median notch between prostomial lobes narrow and shallow (
Fig. 12C
); eyes absent; a pair of internal white ganglia visible through translucent epidermis, dorsolaterally located on prostomium. Median and lateral antennae absent. Palps smooth, tapering, very long (reaching segment 9), inserted on large, rounded palpophores (
Fig. 12C
). Facial tubercle absent.
Tentacular segment fused to prostomium, well developed, with a pair of short lobes, inserted laterally and slightly below prostomium; without acicula or chaetae; tentaculophores large, bulbous, equal sized; dorsal tentacular style smooth, tapering, short (reaching segment 4); ventral tentacular style missing (
Fig. 12C
). Pharynx not everted. Second segment with elytrophores, subbiramous parapodia, chaetae and ventral cirri.
Nine pairs of large, globular elytrophores (
Fig. 12B, D
) present on segments 2, 4, 5, 7, 9, 11, 13, 15 and 17 (all elytra missing); with dorsal cirrophores on last segments.
Cirrigerous segments with large, bulbous dorsal cirrophores (
Fig. 12B
), inserted subdistally on notopodia; styles missing.
Segments 6 and 8 with large, swollen dorsal structure (
Fig. 12A, B
), located basally to cirrophores, interiorly whitish; smaller on segment 6, bigger on segment 8. Dorsal tubercles absent.
Ventral cirri smooth, tapering, present from segment 2 to last segment; inserted basally on neuropodia of segment 2, style long (longer than tip of neuroacicular lobe); in subsequent segments inserted medially on neuropodia (
Fig. 12D
), style short (shorter than tip of neuroacicular lobe).
Parapodia subbiramous; notopodia reduced, much short than neuropodia (
Fig. 12D
). Notopodia arising from the dorsum as two thickened ridges; narrow, subtriangular, tapering into long acicular lobe, tip of notoacicula not penetrating epidermis. Neuropodia large, rectangular to subtriangular, tapering into long acicular lobe, tip of neuroacicula not penetrating epidermis. Notochaetae variable in number (one to 16 observed), long, slender, slightly curved with distinct, faint spinous rows on convex side, with blunt tips preceded by subdistally smooth margin (
Fig. 12E
); notochaetae more slender than neurochaetae. Neurochaetae of
two types
: (1) moderate in number (12–28 observed), long to very long, distally flattened to concave, serrated along both margins, with pointed tips (
Fig. 12F
); and (2) middle and lower group on segments 3–7 modified, moderate in number (16 observed), stouter, short to long, distally flattened to concave, with coarse spines along both margins, spines concentrated basally and well spaced later, middle part with smooth margins (most of or less of their length), subdistally smooth or with one or two spines, blunt tip, tip margin slightly lighter (
Fig. 12G, H
).
Nephridial papillae present on segments 11, 12 and 13, small, bulbous. Last segment very reduced. Pygidium rounded, not enclosed by last segment; with terminal anus (
Fig. 12A
). Anal cirri lost, scars not seen.
Figure 12.
Hodor hodor
gen. nov., sp. nov
.
, holotype MNHN-IA-TYPE 1825 (A–H). A, dorsal view of a preserved complete specimen. B, dorsal view of segments 6 and 8 with swollen dorsal structure, segments 5
–
10. C, anterior end, dorsolateral view, chaetae omitted. D, left parapodia, posterior view, segment 9. E, notochaeta with very faint spinous rows, segment 12. F, neurochaeta, segment 11. G, stouter neurochaeta, lower group, segment 7. H, stout neurochaeta, lower group, segment 4. Abbreviations: ci, cirrophore; el, elytrophore; sw, swollen dorsal structure.
Remarks:
Hodor hodor
gen. nov., sp. nov.
presents many similarities with
Hodor anduril
gen. nov., sp. nov.
, including the number of segments, prostomium and parapodial shape, chaetae and number of nephridial papillae pairs. However, the palps in
Hodor hodor
gen. nov., sp. nov.
are longer (reaching segment 9) than the palps in
Hodor anduril
gen. nov., sp. nov.
(reaching segment 2). Furthermore, the average K2P distance between these species was 14.2% for
COI
and 6.1% for 16S. Interestingly, the morphological variation observed in
Hodor anduril
gen. nov., sp. nov.
specimens could also indicate some dissimilarity within
Hodor hodor
gen. nov., sp. nov.
specimens, which will necessitate care in the identification of any further specimens. In addition, both species have overlapping distribution in APEI#3.
Etymology:
This species is dedicated to
Hodor
, one of P.B.’s favourite characters in the novel ‘
A song of ice and fire
’ by George R. R. Martin.
Genetic data:
DNA sequencing for this species was successful for
COI
, 16S and 18S.
Distribution:
Only
one specimen
was sampled at a single station within the Clarion-Clipperton Fracture Zone in APEI#3 area (
type
locality).