Six new species of the genus Armandia Filippi, 1861 (Polychaeta, Opheliidae) from Lizard Island (Great Barrier Reef, Australia)
Author
Parapar, Julio
Author
Moreira, Juan
text
Zootaxa
2015
4019
1
577
603
journal article
10.11646/zootaxa.4019.1.19
a552e02c-9ad5-4f9e-aeb0-ff02489dc516
1175-5326
241350
C06C733D-924E-4124-AECA-E5C094C9E588
Armandia tubulata
n. sp.
(
Figs 1
F, 14–16, 18B)
Material examined.
Seven specimens in three samples.
Holotype
: AM W.47327, MI QLD 2370.
Paratypes
: AM W.47328, MI QLD 2337; AM W.47329, MI QLD 2340; AM W.47330, MI QLD 2370 (3); AM W.47331, MI QLD 2370, on SEM stub.
Diagnosis
. Parapodia biramous, with prechaetal lobe, ventral lobe and dorsal cirrus on each parapodium; prechaetal lobe short and asymmetrical, with a ventrally displaced tip. Anal tube long and narrow, tube-like. Tube opening directed posterio-ventrally, appearing obliquely truncate in lateral view; not laterally compressed; posterior border provided with 6 pairs of finger-like anal cirri of about 1/5 as long as dorsal tube length; paired basal cirri and internal unpaired anal cirrus.
Description.
Based on
holotype
. Specimen complete, 11.0 mm long and 1.0 mm wide, with 29 chaetigers. Body slender, slightly tapering towards anterior end and truncated at posterior end. Prostomium conical, provided with a pair of lateral, small red eyes and a dorsal one (
Fig. 14
A); palpode well-developed but short and narrow, twisted (
Figs 14
A, 15A). One pair of ring-shaped nuchal organs (
Fig. 15
B); pharynx eversible (
Fig. 14
A), oral tentacles not seen (but present in
paratypes
;
Fig. 15
C). Branchiae present from
CH
2–
CH
26; last three chaetigers (
CH
27–
CH
29) abranchiate; branchiae short, slightly surpassing parapodium of following chaetiger, not decreasing in length in posterior chaetigers. Parapodia biramous, with prechaetal lobe, ventral lobe and dorsal cirrus on each parapodium (
Figs 14
D–I, 15E–F, 16A–D). Prechaetal lobe short and asymmetrical, with a ventrally displaced tip. Lateral eyespots anterior to parapodia on
CH
7–
CH
17, orange, horizontally oval; those of
CH
7 and
CH
15–
CH
17 smaller than others. Simple capillary chaetae in two bundles, notochaetae generally longer than neurochaetae. Anal tube long and narrow, tube-like, of same width along its length (
Figs 14
B, 16E–F). Anal tube opening directed posterio-ventrally, appearing obliquely truncate in lateral view; not laterally compressed; ventrally as long as about 2 chaetigers, dorsally as long as about 3 chaetigers (
Figs 14
C, 16E). Posterior border provided with 6 pairs of finger-like anal cirri of about 1/5 as long as dorsal tube length (
Fig. 14
B); paired basal cirri and internal, unpaired anal cirrus not observed (but present in one
paratype
, see below).
FIGURE 14.
Armandia tubulata
n. sp.
(holotype AM W.47331). A. Anterior end, left side, lateral view; B. Posterior end, left side, latero-dorsal view; C. Posterior end, ventral view. (D–I) Parapodia, right side: D. CH1, lateral view; E. CH2, lateral view; F. CH3, lateral view; G. CH9, dorsal view; H. CH21, anterior view; I. CH29, dorsal view. White arrow marking position of prechaetal lobe tip.
FIGURE 15.
Armandia tubulata
n. sp.
SEM micrographs (paratype AM W.47331). A. Anterior end, left side, lateroventral view; B. Detail of nuchal organ and CH1; C. Detail of oral tentacles protruding from mouth; D. CH1–CH4, left lateroventral view; E. CH3, frontal view; F. CH12–CH13, lateral view.
Remarks.
The shape of the anal tube of
A. tubulata
n. sp.
resembles that of
A. leptocirris
Grube, 1878
and
A. andamana
Eibye-Jacobsen (2002)
.
Armandia leptocirris
was described from the
Philippine Islands
, and later reported in
Sri Lanka
(
Willey 1905
), the
Solomon Islands
(
Gibbs 1971
) and
South Africa
(
Day 1967, Fig. 25.2.h, as
A. leptocirrus
). The drawing of
A. leptocirris
presented by Day (1971) (
Fig. 17
F) shows an anal tube long and obliquely truncated in lateral view, quite similar to that of
A. tubulata
. Nevertheless, in
A. leptocirris
the anal tube is opened posterio-dorsally instead of postero-ventrally.
Armandia andamana
has not been reported since it was described by
Eibye-Jacobsen (2002)
. This species is similar to
A. longicaudata
but it lacks an unpaired anal cirrus which is present instead in
A. longicaudata
and
A. tubulata
n. sp.
FIGURE 16.
Armandia tubulata
n. sp.
SEM images (paratype AM W.47331). (A–D) Parapodia, lateral view: A. CH12; B. CH20; C. CH23; D. CH26; E. Posterior end, right side, lateral view; F. Detail of anal tube, left side, laterodorsal view.
The
paratypes
of
A. tubulata
n. sp.
measure
9–11 mm
in length, and show that the size and the number of chaetigers are constant. One
paratype
(AM W.47329) has an internal unpaired ventral cirrus. The branchiae are lacking in the last three chaetigers; those and the first chaetiger show a small dorsal elevation in the postchaetal lobe, as it happens in
A. dolio
n. sp.
and
A. paraintermedia
n. sp.
(
Fig. 14
D, I).
Etymology.
The epithet
tubulata
(L.) refers to the tubular shape of the anal tube.
Habitat / Distribution.
A sublittoral species only found in SW LI coast, and almost restricted to Vicki’s Reef sampling sites (85.7%) (
Fig. 1
F). Found from
1 to 10 m
depth on different bottom
types
(dead coral rubble, fine sand and calcareous algae).