Opheliidae (Polychaeta) collected by the R/V Hero and the USNS Eltanin cruises from the Southern Ocean and South America

Opheliid polychaetes collected by the United States Antarctic Research Program and additional material from South America were made available for study through the Smithsonian Institution, Washington, D.C., USA. The Opheliidae from Antarctic seas were treated by Hartman (1966, 1967, 1978), who summarized earlier work and also described several new species. Of the five genera she recorded, two (Travisia and Kesun) have since been synonymized and one, Ammotrypane, has been referred to Ophelina; Hartman’s records therefore encompass four genera, three of which are represented in the present collections. No representatives of Euzonus (Thoracophelia) were found. The following species were recorded from Antarctica in the present study: Ophelia algida n. sp., Ophelina breviata (Ehlers, 1913), Ophelina cf. cylindricaudata (sensu Hartmann-Schröder and Rosenfeldt, 1989), Ophelina nematoides (Ehlers, 1913), Ophelina scaphigera (Ehlers, 1900), Ophelina cf. setigera (Hartman, 1978), Ophelina syringopyge (Ehlers, 1901), Travisia antarctica Hartman, 1967 (emended 1978), Travisia kerguelensis McIntosh, 1885, Travisia kerguelensis gravieri Monro, 1930, Travisia palmeri n. sp. and Travisia tincta n. sp. The new species of Ophelia is distinguished by having branchiae starting on chaetiger 2 (rather than on or after chaetiger 8 as in most species of this genus). Travisia palmeri has 22 chaetigers and is distinguished by long branchiae. Travisia kerguelensis gravieri is raised to full species status and renamed T. monroi. Travisia tincta n. sp., distinguished by a distinctive Methyl Green staining pattern and long branchiae, is described from off Peru.


INTRODUCTION
Collections of polychaetes taken by the United States Antarctic Research Program (USARP) between 1969 and 1982, and additional material collected from off the coast of Peru as part of the Southeastern Pacific Biological and Oceanographic Program (SEPBOP), were made available for study through the Smithsonian Institution, Washington, D.C., USA.Treatment of these materials has been focused at the family level; the present paper covers the Opheliidae in these collections.
The known species of Opheliidae from Antarctic seas were studied by Hartman (1966Hartman ( , 1967Hartman ( , 1978)), who mainly summarized work by Ehlers, Kinberg, and Monro, and also described several new species.Of the five genera Hartman recorded, two (Travisia and Kesun) have since been synonymized and one, Ammotrypane, has been referred to Ophelina; thus Hartman's records encompass four genera, three of which are represented in the present collections.Hartmann-Schröder andRosenfeldt (1989, 1991) examined collections made in the Antarctic by German research expeditions and recorded two species of Travisia and five species of Ophelina.Opheliids from South American areas have been better studied, most recently by Elias and Bremec (2003) from Argentina and Elias et al. (2003) from Brazil.
The following species and genera are included in this paper: Ophelia algida n. sp.
Parapodia biramous, rami small, button-shaped lobes; dorsal cirri lacking; short ventral cirri present or absent.Chaetae all simple capillaries.Branchiae present or absent; if present, cirriform or branched; branchiae present along majority of body, confined to midregion, or confined to anterior and posterior, lacking in midregion.Interramal sensory organs may be present as small eyespots, sensory pits, or papillae.A few preanal segments may be achaetous, telescoped, and/or retractile.Anus terminal; pygidium often prolonged and tubular, ending with circlet of blunt lobes, or two stout ventral lobes and a circlet of dorsolateral papillae, or with papillate tube and long internal cirrus.
Remarks.The opheliids are active burrowers and bottom deposit feeders.They have separate sexes, with spawning taking place in or on the bottom surface; however, some forms become pelagic as sexually mature epitokes.The larvae are planktonic and settle at about the 5-chaetiger stage.Opheliids are well known for their specific distribution patterns, being restricted to substrata with a relatively narrow range of particle size.Some species are characteristic of fine muds, others of relatively coarse sands; some are found at shallow depths, others in deep water.
Currently, nine genera in three subfamilies are recognized (Dauvin and Bellan, 1994).The three subfamilies-Opheliinae, Ophelininae, and Travisiinae-were established by Hartmann-Schröder (1971).The Travisiinae appear to be closely related to the Scalibregmatidae in terms of body form and appearance, whereas the other two have a long slender appearance.Blake (2000) and Rouse (2001) suggested that Travisia Johnston had a close affinity with the scalibregmatids, and a recent cladistic analysis by Persson and Pleijel (2005), based on results of 18S rDNA and 28S rDNA analysis, showed Travisia clearly nested within the scalibregmatids.
Genus Ophelia Savigny, 1818 Type species.Ophelia bicornis Savigny, 1818 Diagnosis (emended).Body divided externally into two regions: an anterior cylindrical region and a posterior region with a deep ventral and two lateral grooves.Prostomium a small pointed cone, lacking appendages; pair of nuchal organs on posterior lateral border.Branchiae present or absent; branchiae, if present, cirriform with single or, rarely, double filaments, present from chaetigers 2 or 8-11, absent from a few posterior preanal segments.Chaetae all simple capillaries; parapodia low rounded lobes.Lateral sensory organs present between parapodial rami.Anal segment with papillae.
Remarks.Tebble (1953) established diagnostic characteristics for the genus Ophelia.Among these, he concluded that the most important were the number of branchiate and abranchiate chaetigers, the presence or absence, and extent if present, of branchial fenestrations (small pores in the lateral groove), and the structure of the posterior region, including the development of dorsal ridges vs telescoping of the segments.At the time of Tebble's work, all of the described Ophelia species had branchiae; however, four abranchiate species have subsequently been described, and the number of valid species in the genus is at least 32 (Bellan and Dauvin, 1991).The present emendation takes into account the presence of branchiae from chaetiger 2 in the new species described below.Hartman (1966) reported two species of Ophelia from the Antarctic: O. bipartita Monro, 1936 andO. praetiosa (Kinberg, 1866), but neither species was encountered in this study.The new species described below was represented by a single specimen from subantarctic Macquarie Island.Three other small and poorly preserved Ophelia specimens were also present: the gut of one of those small specimens contained exceptionally large sand particles and biological remnants, causing one to wonder at the elasticity of the opheliid body.
Parapodia small, broadly rounded, with slightly pointed tip in some chaetigers.Chaetae all delicate golden capillaries in two fascicles, one arising from dorsal side of parapodial lobe, second emerging from base of ventral side of parapodial lobe.Notochaetae long, especially in anterior chaetigers where they arch over dorsum and nearly meet at midline; chaetae of last three or four preanal chaetigers also exceptionally long and form a delicate cage around the anal structure; anal segment itself achaetous.Posterior segments without dorsal longitudinal ridges, these segments slightly telescoped dorsally, pulling (tilting) the anal structure towards the dorsum (Fig. 1).Pygidium with about 16 papillae (processes), ventral papillae only slightly longer than dorsal ones.
Methyl Green staining pattern.Two patches of deep stain on ventral surface of pygidium, otherwise stain not retained.
Etymology.The species name is taken from the Latin algidus, meaning cold, and refers to the first collection of this species from the cold waters of the Southern Ocean.
Remarks.This species appears to combine features from two genera: the origin of the deep ventral groove on chaetiger 7 and the structure of the pygidium, with the associated long capillary chaetae, place this species in the genus Ophelia.However, the shape of the prostomium with a terminal palpode and the origin of the branchiae from chaetiger 2 associate the species with the genus Ophelina.Only one interramal papilla (lateral sense organ), between chaetigers 2 and 3 on one side of the specimen, was noted.The bundles of chaetae on each chaetiger are not widely separated as in many species of Ophelia (i.e.there is only one parapodial lobe with two bundles of chaetae arising from it) giving the appearance of a uniramous rather than biramous condition.Kinberg, 1866. Fide Fauchald, 1977. Omaria Grube, 1869. Fide Fauchald, 1977. Terpsichore Kinberg, 1866. Fide Fauchald, 1977. Urosiphon Chamberlin, 1919. Fide Fauchald, 1977.Diagnosis.Body elongate, not divided into distinct regions; with deep ventral groove and two lateral grooves along entire length of body.Prostomium conical, sometimes with terminal palpode; eyes present or absent.Branchiae present or absent; if present, beginning on chaetiger 2, continuing to posterior end, sometimes absent from middle or far posterior chaetigers; branchiae single, cirriform.Segmental lateral eyes absent.Noto-and neuropodia with small fascicles of capillary chaetae; small ventral cirrus present.Pygidium with anal funnel sometimes bearing long unpaired cirrus and additional lateral cirri.
Remarks.Chamberlin (1919:385) pointed out that the type of Ophelina Oersted (1843), O. acuminata Oersted, is identical with the type of Ammotrypane H. Rathke (1843), A. aulogaster H. Rathke.Chamberlin used Ammotrypane as the valid genus, as did Hartman (e.g. 1967) and other authors.However, Støp-Bowitz (1945) noted that Marenzeller (1892) determined that Oersted's work had been published before Rathke's, and therefore Ammotrypane was the junior synonym of Ophelina.Hartmann-Schröder (1971) and Fauchald (1977) recognized Ophelina as the valid name for the genus, and subsequent authors have followed this version of the synonymy.
The anal funnel is a highly diagnostic feature of Ophelina species, but it is often broken off, especially if specimens are handled roughly during sampling and preservation.Species that are described as lacking the anal funnel are most likely based on specimens where this structure has been lost.Following this observation, Blake (2000), in treating Ophelina species from California, referred O. pallidus (Hartman, 1960) to synonymy with O. acuminata Oersted, 1843.The Antarctic species O. gymnopyge (Ehlers, 1908), also described as lacking an anal funnel, is therefore similarly questionable, and records of that species (Hartman, 1966;Hartmann-Schröder andRosenfeldt, 1989, 1991;Elias et al., 2003) should be treated with caution as they most likely are damaged specimens of other species.Blake (2000) pointed out that although the number of chaetigers is fixed in certain opheliid species, this condition does not appear to pertain to Ophelina acuminata, a common, perhaps cosmopolitan opheliid, in which segments are added with continued growth; he concluded that the number of chaetigers is not an important characteristic in this genus.Hartman (1966Hartman ( , 1967Hartman ( , 1978) ) included six named species of Ophelina (as Ammotrypane) from Antarctic waters: Ophelina breviata (Ehlers, 1913), O. gymnopyge (Ehlers, 1908), O. nematoides (Ehlers, 1913), O. scaphigera (Ehlers, 1900), O. setigera Hartman, 1978, andO. syringopyge (Ehlers, 1901).She also suggested that two additional species might be present in her collections: a branchiate species having nine bifid papillae on the anal funnel, and an abranchiate species that cooccurred with O. nematoides.Hartmann-Schröder and Rosenfeldt (1989) reported O. cylindricaudata (Hansen, 1878) as a new record for the Antarctic; this species was also reported by Hilbig (2001) andSicin ´ski (2004).
Methyl Green staining pattern.No discernable pattern.
Remarks.Ophelina breviata has branchiae present on all chaetigers except the first and the last four, but Hartman (1978) noted that her material from the Weddell Sea and Hero Inlet lacked branchiae on the majority of middle body chaetigers, perhaps because of damage.The absence of branchiae from the middle region suggests that some of Hartman's material may represent a species distinct from O. breviata; perhaps O. cylindricaudata (Hansen, 1878), as reported by Hartmann-Schröder and Rosenfeldt (1989) as a new record for the Antarctic.
O. breviata was recently recorded in deep water on the continental slope off the Farallon Islands in northern California (Maciolek and Blake, unpublished data).Ophelina cf.cylindricaudata (Hansen, 1878) (sensu Hartmann-Schröder and Rosenfeldt, 1989) Ophelina cylindricaudata (Hansen, 1878) Diagnosis.Body long, linear, 17-34 mm long, up to 2 mm wide; segments number 24-28; body with longitudinal ventral groove; last four chaetigers characteristically short and crowded, pushed towards median ventral line.Prostomium conical, longer than wide, with rounded edge, palpode absent; with pair of large, well-developed nuchal organs at base of prostomium.Branchiae cirriform, present on chaetigers 2-9, absent from mid-body region, present on last six of 10 chaetigers, last four crowded chaetigers without branchiae.Anal cylinder long, smooth or faintly and irregularly ringed, with the dorsal edge obviously longer than the ventral edge; ventral filament of anal tube, subtriangular, wider at base, tapering to narrow tip, wrinkled in appearance.
Methyl Green staining pattern.No discernable pattern.
Remarks.Hansen (1878) described Ophelina cylindricaudata (as Ammotrypane cylindricaudatus) from two specimens collected in 763 and 911 m off the coast of Norway.The species was described as having a long anal funnel ending with a dorsal papilla overhanging a shorter, wider ventral lip (see Hansen, plate VI, fig.3).Neither Hansen (1878) nor Fauvel (1914Fauvel ( , 1927) mentioned a long ventral filament associated with the anal tube, but this feature appears in descriptions provided by Støp-Bowitz (1945, 1948).Hartmann-Schröder andRosenfeldt (1989, 1991) accepted the description and illustration by Stop-Bowitz (1945), and recorded the species from the Antarctic.However, it is possible that the Antarctic species is not the same as O. cylindricaudata (Hansen), which has been recorded primarily from Arctic waters.An analysis encompassing additional material from both Arctic and Antarctic waters is necessary before a conclusion can be reached regarding the Antarctic material.Ophelina nematoides (Ehlers, 1913) Ammotrypane nematoides Ehlers 1913, pp. 524-525. Hartman, 1966, p. 49. Hartman, 1978, p Diagnosis.Body thin, threadlike, resembling a nematode.Reported length 30 mm, width 1 mm for 30 chaetigers; present material 4 mm and 0.2 mm wide for ca.18 chaetigers, not including anal funnel, which is missing on all specimens.Prostomium bluntly conical, about as long as first 2 segments, terminating anteriorly in a palpode.Ventrum with longitudinal medial groove; lateral grooves also present.Segments not annulated.Parapodia small, rounded.Branchiae absent.Pygidium (described) with an annulated cylindrical postanal cylinder, about as long as last two segments.
Methyl Green staining pattern.No particular staining pattern; stain is taken up uniformly except for the very tip of the prostomium and posterior end, which do not stain.Ventral groove does not appear as stripe as in O. syringopyge.
Remarks.In Hartman's (1978) description of the species, she mentions a short slender median antenna inserted slightly behind the tip of the prostomium, but she is undoubtedly referring to the palpode at the anterior edge.
Methyl Green staining pattern.The large palpode on the prostomium and the everted nuchal organs were the only two structures that did not retain stain.
Remarks.The distinctive anal funnel on this species is remarkably similar to that found on the widespread species Ophelina acuminata.Elias et al. (2003) report O. cf.acuminata from 33-71 m off SE Brazil, but their material has branchiae on all chaetigers, except the first.They did not consider O. scaphigera.However, until such time as Ehlers types can be examined and compared with O. acuminata, no further conclusions can be drawn.The present record extends the depth range of this species from 385 m to 3382 m.
Methyl Green staining pattern.No particular pattern.
Remarks.Hartman (1978) distinguished O. setigera by the long chaetae in the first few chaetigers; in addition, the multiannulate appearance of the chaetigers and the gradual diminishing in size of the last 16 (of 43) chaetigers appear to be specific characteristics.The present material differs from Hartman's description in that although the animals are much larger (260 mm vs 40 mm long), there are fewer chaetigers (28 vs 43).Also, the posterior chaetigers do not diminish in size but remain essentially equal throughout, with the exception of the last four, which are characteristically short and crowded together.
Methyl Green staining pattern.No particular pattern, although the ventral groove stains darker than surrounding tissue and appears as a long thin ventral stripe.The lateral area along the parapodia also stains a bit darker.Otherwise, the stain is taken up uniformly.
Remarks.The name Ammotrypane aulopyge was used by Ehlers in 1897 to describe a new species; he later (1901) determined that the name was a homonym of a Grube species, and therefore replaced it with A. syringopyge.
This species was the most common opheliid in the collections.The anal funnel is easily detached and care should be taken that specimens lacking the funnel are not misidentified as another species.One specimen in the collection has a single gill with three branches; this anomaly is not considered significant at this time.Several specimens (e.g. from Hero 1912 and several other samples) were full of large eggs.
Remarks.Chamberlin (1919) renamed the genus Dindymene, established by Kinberg (1866), to Dindymenides, having determined that the former was preoccupied in the Crustacea.Dindymenides has not been widely reported (perhaps three records) and has consisted of a single species, D. concinna, described by Kinberg from 5-20 m in Algoa Bay, in tropical South Africa.Hartman (1948) examined Kinberg's material and was of the opinion that the type specimen had been unnaturally flattened in the vial, and that, contrary to Kinberg's description, the first chaetae were in front of the oral aperture, rather than behind it, thus questioning the validity of the genus.Bellan et al. (1990), following Fauchald (1977), retained the genus as distinct, but Dauvin and Bellan (1994) preferred to consider it invalid, citing Hartman (1948) and a recent opinion by Fauchald (in litt.).Chamberlin (1919) also established a new genus, Kesun, which he differentiated from the related genus Travisia by the complete absence of branchiae.
Following a cladistic analysis of morphological characters, Dauvin and Bellan (1994) synonymized both Kesun and Dindymenides with Travisia, and recognized a total of 27 species and three subspecies in the genus.Characters that are important at the species level include the presence of lobes or papillae on the pygidium, the position and relative size of the nephridiopores, and the total number of chaetigers, which appears to be relatively stable in most, but not all, species (Dauvin and Bellan, 1994).Blake (2000) also found the number of segments to be important in Travisia; however, if the number of segments is not fixed for the parent species, the validity of a (sub)species based solely on a differing number of segments is highly questionable.For example, Travisia kerguelensis is described as having 23-27 segments, and the subspecies T. kerguelensis gravieri as having 25.Similarly, T. olens has 29-36 segments, and the subspecies T. olens novae zealandiae, 38-40.Other characters are also necessary to support the retention of the species or subspecies.In the example of T. kerguelensis gravieri, the original illustrations and description by Monro suggest that this form, in lacking pygidial papillae but having two short dorsal anal cirri, may be separate from T. kerguelensis at the species, rather than the subspecies, level.Hartman (1966Hartman ( , 1967Hartman ( , 1978) ) recorded seven species of Travisia from Antarctica and surrounding waters, including T. antarctica Hartman 1967; T. kerguelensis McIntosh, 1885; T. kerguelensis gravieri Monro, 1930;T. lithophila Kinberg, 1866;T. nigrocincta Ehlers, 1913;T. olens Ehlers, 1897;and T. profundi Chamberlin, 1919.She also recorded Kesun abyssorum Monro, 1930, which Dauvin andBellan (1994) referred to Travisia glandulosa McIntosh, 1879.Of these eight species, three are in the present collections, plus one new species from the Antarctic Peninsula; the other new Travisia is from additional collections off Peru.
Methyl Green staining pattern.No pattern, although the stain outlines the papillae, making the size and arrangement easier to observe.
Remarks.The species was described as being unique because it has 28 segments, of which 20 or 21 are branchial; the last four segments lack chaetae.Many of the specimens examined have lost branchiae.The most notable feature of this species is the rows of papillae on the body surface, which, as Hartman wrote, resemble closely-strung beads.
The majority of records for this species are from 2000 m and deeper; however, good specimens from approximately 140 m were recorded from the present material.
Methyl Green staining pattern.No pattern.
Remarks.The notched shape of the posterior parapodia is distinctive.Earlier descriptions have used the words "lacinated" or "crenulated" to describe this shape, but those words imply a structure that has a fringed margin (lacinated) or has low, rounded teeth (crenulated), and do not convey the actual shape of the body part being described."Crenellated," meaning "indented or notched," is more accurate.
Remarks.The subspecies T. kerguelensis gravieri was described by Monro (1930) from 259-315 m off the Palmer Archipelago.Although Dauvin and Bellan (1994) recognized the subspecies, they pointed out that separation of the closely related forms is difficult, since the number of segments overlap.However, the differences noted by Monro (1930, p.167) focus on the absence of papillation (or laciniation) of the terminal segments, and in the presence of a pair of short dorsal anal cirri at the end of the anal cylinder.The single specimen in the present material has the two longer dorsal anal cirri described by Monro, and although the parapodia are developed in several posterior chaetigers as they are in T. kerguelensis, there is no hint of crenellations on any of the posterior segments.The specimen has numerous white sand grains adhering to the body surface, but these are not papillae, and indeed papillae seem to be absent from the posterior chaetigers.
These differences suggest that this form is a valid full species rather than subspecies, and herein is raised to species level.However, the name Travisia kerguelensis gravieri is a homonym of a species described by McIntosh (1908), and a new name is therefore required for the Monro species.Description.Holotype a large, bulky specimen, measuring 22 mm long and from 2 mm (anterior tip) to 5 mm (posterior) wide for 24 chaetigers (Fig. 2A).Epidermis highly papillated, papillae all small, similar; segments triannulate except for last four or five.Parapodial lappets present from chaetigers 15-16, becoming larger through last segment.Notopodial and neuropodial chaetal rami well separated; chaetae all capillaries.Branchiae from chaetiger 2, triangular, elongated, annulated (Fig. 2B).Branchiae number 22 pairs, pairs 1-3 and 5-8 short, pair 4 with long tip, pairs 9-12 very long, extending the length of 3-4 chaetigers, distal portion becoming very long, thin; pairs 13-14 shorter, but still with long tip; thereafter branchiae very short.Lateral pores obvious between parapodial rami on chaetigers 1-20 (Fig. 2B), either hidden or absent on last four chaetigers.Pygidium shifted laterally, appearing to terminate on side of animal (Fig. 2D); anal aperture appearing puckered, with two larger, broad ventral cirri (Fig. 2C).
Methyl Green staining pattern.No particular staining pattern, although when first removed from the stain, the tip of the prostomium, lips of the lateral pores, and internal rim of the anal opening did not retain any stain.As the stain differentiates, the branchiae clear first, then segmental bands (between the annulations on the segments), and eventually all of the body tissues are clear of stain.
Etymology.This species is named after the general location of the first collection of this species, near Palmer Station on the Antarctic Peninsula.Remarks.The long gills on chaetigers 9 through to 12 may be similar to the long branchiae in T. lithophilia; however, that species has 52-53 chaetigers compared with the 22 chaetigers (26 segments) in the new species.The very odd orientation of the pygidium is not understood at this time.Either it is due to an artifact that occurred during collection and fixation (NJM), or it is real (JAB).If the latter, it is very unusual.Description.Holotype complete, damaged in mid-body region; measures 13 mm long and 2 mm wide for 21 chaetigers plus pygidium.Proboscis soft pouch, everted on holotype.Segments biannulate in anterior, triannulate posteriorly.No parapodial lamellae on chaetiger 1, both notochaetae and neurochaetae present (Fig. 3A); subsequent parapodia with very small lamellae.
Methyl Green staining pattern.A very distinctive staining pattern, with the majority of the prostomium and peristomium staining deeply, except for the tip and a bright white (non-staining) band near the middle of the prostomium (Fig. 3A).
Etymology.The species name is taken from the Latin tinctus, and refers to the retention of Methyl Green stain by this species.
Remarks.The extremely long branchiae in the middle body segments, plus the anterior Methyl Green staining pattern are unique.