Orbiniella annulata Hartman 1967
Creators: name: Blake, James A.
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Orbiniidae
Orbiniella
Orbiniella annulata

description: Orbiniella annulata (Hartman, 1967)
Figure 54 A–C
Falklandiella annulata Hartman, 1967: 109 –110, pl. 35; Buzhinskaja 1992: 76 –77.
Material examined. Falkland Islands, Eltanin Sta. 8-558, 14 Mar 1963, 51.48°S, 56.63°W, 646–845 m, holotype (USNM 55536).— South Pacific Ocean, off Tasmania, Eltanin Sta. 16-1418, 86– 101 m (1, USNM 60629).
Description. A small species, holotype 3.3 mm long, 0.48 mm wide for 34 setigerous segments; Tasmanian specimen only 1.5 mm long and 0.25 mm wide for 21 setigers. Body not divided into regions; segments simple, with reduced parapodia throughout, tapering somewhat posteriorly.
Prostomium sub-triangular not acutely pointed (Fig. 54 A); eyespots not apparent (red eyespots reported from holotype by Hartman (1967) no longer discernable). Peristomium with two achaetous rings. Branchiae absent (Fig. 54 A).
Species Body shape Prostomium Peristomial Eyespots Segmental Noto/Neuro Capillary setae Noto/neuro Gametes Pygidium Distribution/depth range;
rings annulations post setal acicular References lobes or spines
lamellae
aciculata Short, thick, Broađly 2 complete, Absent Uni- anđ Absent Crenulateđ 1%4 large, Absent With 2 Galapagos Rift, from seđiments
Blake, 1985 only 3.2 mm rounđeđ on one or both biannulate conspicuous, short anal near hyđrothermal vents, 2730 long anterior narrow acicular spines cirri m. Blake 1985. margin in both noto-
anđ
neuropođia
andeepia Elongate, Broađly 2 complete, Absent; Uniannulate Present, Crenulateđ Notopođia Eggs Bilobeđ, Antarctica: Drake Passage,
Narayanaswamy with up to 68 rounđeđ relatively pigmenteđ notopođia with 1 spine; present in with 2 short Weđđell Sea, South Sanđwich
Blake, 2005 setigers anđ anteriorly narrow nuchal only neuropođia largest cirri Slope, 2257% 5338 m. 120 mm long organs with 2 spines specimens Narayanaswamy & Blake 2005;
present This stuđy.
annulata Elongate, Triangular, 2 complete Present, Uniannulate Absent Crenulateđ anđ 1%2 smooth Absent With 2 Falklanđ Islanđs, 646% 845 m;
Hartman, 1967) thick, with weakly original smooth neuro aciculae rounđeđ off Tasmania, 86% 101 m. narrow pointeđ đescript; lobes Hartman 1967; This stuđy. segments no longer
visible
dayi Branch, Elongate, Broađly 2 complete Absent Weakly Present, small Crenulateđ 1%2 Absent With 2 Inđian Ocean, Marion Islanđ,
1998 narrow, rounđeđ biannulate throughout neuropođial rounđeđ intertiđal to 15 m. Branch 1998. tapering acicular spines lobes posteriorly; in posterior
up to 5 mm segments
long
hobsonae Elongate, Rounđ on 2, 1st narrow; absent Uniannulate Absent Crenulateđ 1%2 crenulateđ Absent Simple, NE Pacific, Juan đe Fuca Riđge,
Blake & Hilbig, threađlike, anterior 2nđ large; (barbeđ) acicular spines without Enđeavour Seamount, vent site,
1990 4.5 mm long margin both throughout in both noto- lobes or 2216 m. Blake & Hilbig 1990.
complete anđ cirri neuropođia
landrumae n. Short, thick Broađly 2 not 2 ređ, Uniannulate Short, noto Crenulateđ 1%4 elongate Eggs With 4 anal Juan Fernanđez Islanđs,
. anteriorly, rounđeđ, complete crescent- postsetal lobes throughout crenulateđ present, cirri, đorsal intertiđal to low water. This tapering smooth on đorsally shapeđ throughout; neuro spines 190 µm pair short, stuđy. posteriorly; anterior eyespots present in with broađ triangular; segments margin present anterior blađes; N.B. ventral pair narrow neuropođia, notopođial long, absent flail anđ cirriform posteriorly furcate
notosetae
present
……continued on the next page Species Body shape Prostomium Peristomial Eyespots Segmental Noto/Neuro Capillary setae Noto/neuro Gametes Pygidium Distribution/depth range;
rings annulations post setal acicular References lobes or spines
lamellae
marionensis Short, up to Short, 2 complete Absent Biannulate(2) Noto- anđ Crenulateđ 2%4 acicular? Rounđeđ Inđian Ocean, Marian Islanđ,
Gillet, 1999 7 mm long, broađly neuropođial- spines from with one 95% 201 m. Gillet 1999. 1.3 mm wiđe rounđeđ postsetal lobes setiger 1 pre-anal present present; N.B. segment notopođial
furcate setae
present(3)
minuta Day, Short, Semi- 2 complete Absent Weakly Absent Crenulateđ Short aciculae? With 2 South Atlantic, Tristan đe narrow, only circular, biannulate barely rounđeđ Cunha, intertiđal. Day 1954. 2% 3 mm long broađly emerging in lobes
rounđeđ miđđle anđ
anteriorly posterior
segments
nuda Hobson, Elongate, Broađly 2 incomplete 2 Uniannulate Absent “spinous” 2%4 Sperm Bilobeđ NE Pacific, Washington, narrow, 5%11 rounđeđ subđermal capillaries neuropođial present; intertiđal. Hobson 1974. mm long anteriorly aciculae eggs not
observeđ
petersenae Elongate, Broađly 2 complete absent Bi anđ Present Crenulateđ 1%3 smooth Present, With 4 NE Atlantic, 133% 197 m anđ
Parapar et al. narrow, rounđeđ triannulate(4) notopođia noto- anđ oocytes short lobes 1490% 1915 m. Parapar 2015 (6); anteriorly only, small neuroaciculae ca. 60 unpublisheđ đata by the late µm (5) Mary E. Petersen.
plumisetosa Elongate, Broađly 2 complete 2 black Uniannulate Absent short smooth 2%4 curveđ Eggs With 2 Commanđer Islanđs, Bering Sea,
Buzhinskaja, weakly rounđeđ on subđermal caps + neuroaciculae present rounđeđ intertiđal. Buzhinskaja 1993. fusiform, anterior eyespots Crenulateđ caps 225 µm; lobes
narrow margin with long sperm
posteriorly plumose fibrils packets
present
spinosa n. sp. Elongate, Elongate, 2, not Absent Uniannulate Absent Crenulateđ 1%2 curveđ Absent With 2 Off Argentina on đrifting kelp. narrow, with rounđeđ complete throughout neuro spines blunt lobes This stuđy. short anteriorly đorsally with barbeđ or
segments hirsute tips
uniformis Long, linear, Short, 2, not Absent Uniannulate Absent Crenulateđ, 2%3 emergent Eggs With 2 Antarctic Peninsula, shallow
Hartman, 1967 most broađly complete most thicker pointeđ neuro present, large water; Hartman 1967; This segments as rounđeđ on đorsally with curve on aciculae 150 µm ventral stuđy. long as wiđe anterior shaft lobes; 2 margin short đorsal cirri
Not incluđing O. branchiata, likely a juvenile of another orbiniiđ; not incluđing O. drakei, herein transferređ to Leitoscoloplos; (2) Baseđ on SEMs (Gillet 1999: Figs. 2 B%C); (3) Notopođial furcate setae are
clearly present in last notopođium on the right siđe of the SEM figuređ by Gillet (1999: Fig. 2 D); (4) Line đrawings in Parapar et al. (2015: Fig. 3) show only uniannulate segments along the bođy; (5)
Measurements of oocytes taken from unpublisheđ đata on this species by the late Mary E. Petersen, who left đetaileđ illustrations anđ notes. (6) Two đistinct đepth ranges suggest that two species are present rather
one.
Parapodia represented by low mounds from which setae project; dorsal and ventral cirri absent. Notosetae including crenulated and smooth capillaries from very thin to heavy (Fig. 54 C); neurosetae including crenulated capillaries with thickened shafts, tapering abruptly to long thin tips, and 1–2 smooth aciculae, first present from about setiger 12 (Fig. 54 B).
Pygidium with terminal anus between two rounded lobes; without anal cirri (Fig. 54 A).
Remarks. Hartman (1967) considered that Falklandiella annulata was related to orbiniids, but stopped short of referring the genus to the family. After examining the holotype from the Falkland Islands and the new specimen from off Tasmania, it is clear that the species should definitely be referred to the Orbiniidae. The crenulated capillaries and the heavier serrated setae are distinctive for orbiniids. There is no apparent separation of the body into a thorax and abdomen, and this is what caused Hartman (1967) the most difficulty in interpretation. The lack of distinct body regions is however, characteristic of species of Microrbiniinae and this species should be referred to the genus Orbiniella, first suggested by Buzhinskaja (1992) and confirmed here.
Among the nine shallow-water species listed in Table 2, Orbiniella annulata is most similar to O. nuda and O. plumisetosa in having eyespots and to the latter species in having complete peristomial rings instead of dorsally incomplete. Orbiniella annulata was described with red spots, whereas O. plumisetosa was reported to black subdermal eyespots. However, upon re-examination the eyespots were not visible in the holotype of O. annulata, having faded after 50 years in preservative.
Distribution. Falkland Islands, 646–845 m; off Tasmania, 86– 101 m.
description: Published as part of Blake, James A., 2017, Polychaeta Orbiniidae from Antarctica, the Southern Ocean, the Abyssal Pacific Ocean, and off South America, pp. 1-145 in Zootaxa 4218 (1) on pages 109-113, DOI: 10.5281/zenodo.245827