Revision of Brada Stimpson, 1853, and Bradabyssa Hartman, 1967 (Annelida, Flabelligeridae)
Author
Salazar-Vallejo, Sergio I.
text
Zootaxa
2017
2017-11-03
4343
1
1
98
journal article
31638
10.11646/zootaxa.4343.1.1
2b60af66-f747-47b2-8e43-2eb333131a4b
1175-5326
1041210
6E46EE12-D51F-48B0-BC66-0EBBAF9FA981
Bradabyssa tzetlini
(Jirkov & Filippova
in
Jirkov, 2001)
n. comb.
Figure 44
Brada
tzetlini
Jirkov & Filippova, 2001: 356
–357,
Figs 1–5
.—Oug
et al
. 2011: 14,
Figs 1–4
(reprod. from Jirkov & Filippova, 2001).
FIGURE 44.
Bradabyssa tzetlini
(Jirkov & Filippova
in
Jirkov, 2001)
n. comb.
, syntype (HDMSU 21.07.1957): A. Anterior region, dorsal view. B. Same, right lateral view (arrow points to gonopodial papilla). C. Same, ventral view (arrows point to gonopodial papillae). D. Same, chaetiger 13, right parapodium. E. Same, basal, medial and distal notochaetal regions. F. Same, basal, medial and distal neurochaetal regions. Scale bars. A: 1.1 mm, B: 0.7 mm, C: 1 mm, D: 0.2 mm, E: 80 µm, F: 80 µm.
Type material
.
Norwegian Sea
. Syntype (HDMSU
21.07.1957
), R.V. Sevastopol, Cruise 5, Sta. 1116 (63.0° N, 02.25° E),
950 m
,
21 Aug. 1957
. Syntype (HDMSU
27.09.1958
), dried-out, R.V. Sevastopol, Cruise 10, Sta. 1702 (66.38° N, 04.59° E),
1125 m
,
27 Sep. 1958
(cephalic cage
1.5 mm
long, 2 notochaetae and 2 neurochaetae in chaetiger 1). Syntype (HDMSU
15.10.1958
), R.V. Sevastopol, Cruise 10, Sta. 1766 (65.13° N, 00.10° E),
730 m
,
15 Oct. 1958
, Agassiz trawl (two anterior fragments of mature females, partly dehydrated; oocytes about 125 µm). Syntype (HDMSU
4.11.1959
), dried-out, R.V. Sevastopol, Cruise 15, Sta. 2444 (69.2° N, 00.08° E),
1000 m
,
4 Nov. 1959
(parapodia with 4 notochaetae and 4 neurochaetae per ramus). Syntype (HDMSU
30.06.1978
), R.V. Tunetz, Cruise 105, Sta. 16 (72.5° N, 00.14° E),
960 m
,
30 Jun. 1978
(complete, slightly swollen anteriorly,
13 mm
long,
3 mm
wide, cephalic cage
2 mm
long (5 notochaetae, 4 neurochaetae), 30 chaetigers, gonopodial lobes in chaetiger 5, each digitate with tip black, posterior end with anus dorsal, anus with a thick black muscular ring, without anal cirri. Notochaetae 4–5, in transverse series, neurochaetae 4–5, in oblique series; notochaetae about 1/3 as long as body width, 5 transverse series of dorsal papillae).
Description
. Better preserved
syntype
(HDMSU
21.07.1957
) broken in two fragments; body whitish, papillae light brown (
Fig. 44A
), ventrally flat, blunt at both ends; 24(11+13) mm long,
4 mm
wide, cephalic cage
1.8 mm
long, 34(13+21) chaetigers. Papillae covered by fine sediment grains. Papillae very long, larger dorsally, arranged in 5–6 transverse series, shorter ventrally (
Fig. 44B
); posterior chaetigers with larger papillae, basally swollen, globular with long tip. Smaller
syntype
(HDMSU
30.06.1978
)
13 mm
long,
3 mm
wide, cephalic cage
2 mm
long, 30 chaetigers.
Anterior end not dissected. Cephalic cage chaetae broken; in another syntype (HDMSU
30.06.1978
) chaetae 2.0 mm long. Only chaetiger 1 involved in cephalic cage; chaetae arranged in short lateral series, with 5 notochaetae and 4 neurochaetae per bundle.
Anterior margin of first chaetiger papillated, papillae short, rounded, eroded. Anterior chaetigers without especially long papillae. Chaetal transition from cephalic cage to body chaetae abrupt; aristate neurospines present from chaetiger 2. Gonopodial lobes in chaetiger 5 (
Fig. 44B, C
), blunt, digitate, tip slightly darker.
Parapodia well developed, lateral (
Fig. 44D
). Median neuropodia ventrolateral. Notopodia and neuropodia close to each other. Notopodia with chaetal lobe short, rounded, with 3–4 long papillae, longest about 1/3 as long as notochaetae.
Median notochaetae arranged in short transverse series, most notochaetae multiarticulate capillaries with articles short basally and medially, become long distally (
Fig. 44E
); about 4–5 notochaetae per bundle, about half as long as body width. Neurochaetae multiarticulate capillaries in chaetiger 1; posterior chaetigers with aristate neurospines, arranged in short transverse series, 4 per bundle. Each neurospine with short rings basally and medially, distally tapering, hyaline with long falcate mucro (
Fig. 44F
).
Posterior end rounded, truncate; pygidium with anus terminal, thick, anal cirri absent. Oocytes in a mature anterior fragment (HDMSU
15.10.1958
), about 125 µm.
Remarks.
Bradabyssa tzetlini
(Jirkov & Filippova
in
Jirkov, 2001
)
n. comb.
belongs to a group of species having 28–33 chaetigers and dorsal papillae with adhering sand particles, which includes
B. pluribranchiata
(Moore, 1923)
n. comb.
and
B. setosa
(Verrill, 1873)
n. comb.
However,
B. tzetlini
differs from these other species by having gonopodial papillae with pale stems and dark tips, whereas the other species possess completely pale ones.
Distribution
. Scandinavian waters, Norwegian Sea, in
700–1200 m
water depth.