New species and records of Heterospio (Annelida, Longosomatidae) from continental shelf, slope and abyssal depths of the Atlantic Ocean, Pacific Ocean, Indian Ocean and adjacent seas.

Nineteen species of the rare polychaete genus Heterospio are reported, 15 of which are new to science. The status of H. longissima Ehlers, 1874, the type-species, is reviewed. The specimens examined are from several locations in the North Atlantic Ocean, Gulf of Mexico, Caribbean Sea, off Br azil, the Indian Ocean, the Pacific Ocean off California, New Zealand, Australia, and the South China Sea. Deep-water samples from the western North Atlantic Ocean collected by the late Drs. H.L. Sanders and R.R. Hessler that were reported by Hartman as H. longissima were re-examined and referred to two new species, H. hartmanae n. sp. (abyssal depths, New England to Bermuda transect) and H. guiana n. sp. (bathyal depths off Suriname). Other materials from the Sanders/Hessler North Atlantic collections were also examined and referred to two additional species, H. canariensis n. sp. (deep water off Canary Islands) and H. southwardorum n. sp. (Bay of Biscay) as well as H. cf. reducta from off SW Ireland in bathyal depths. New collections from the North Atlantic region include additional materials of H. hartmanae n. sp. (deep water off the Mid-Atlantic and SE USA), H. aruba n. sp. (Caribbean Sea), H. bathyala n. sp. (deep water off SE USA), and H. dibranchiata n. sp. (deep water, Gulf of Mexico). Heterospio paulolanai n. sp. is from shelf depths off southeastern Brazil. Heterospio knoxi n. sp. is from the North Island of New Zealand, H. ehlersi n. sp. is from the Gulf of Thailand, in the South China Sea, H. bidentata n. sp. is described from deep water in the Coral Sea off eastern Australia, and H. alata n. sp. and H. brunei n. sp. are described from deep water off the Island of Borneo in the South China Sea. Heterospio africana n. sp. and H. antonbruunae n. sp. are described from off east Africa in the Mozambique Channel. New records and descriptions of H. catalinensis, H. indica, and H. peruana are presented. The 15 new species reported here nearly triple the number of previously known species of Heterospio, with 23 species now recognized. All known species are tabulated and compared.

New species and records of Caulleriella, Chaetocirratulus and Chaetozone (Annelida, Cirratulidae) from continental shelf and slope depths of the Western North Atlantic Ocean.

Seventeen species of cirratulid polychaetes, 13 new to science, are reported from continental shelf and slope depths of the western North Atlantic Ocean. The samples were collected as part of deep-water offshore reconnaissance surveys from New England to the Carolinas and long-term monitoring programs in Boston Harbor, Massachusetts Bay, and Georges Bank off Massachusetts. The new species are included in the genera Caulleriella (C. cryptica n. sp.), Chaetocirratulus (C. hessleri n. sp., C. sandersi n. sp., and C. tomaculus n. sp.), and Chaetozone (C. adunca n. sp., C. artaspinosa n. sp., C. brychiata n. sp., C. castouria n. sp., C. donerae n. sp., C. lophia n. sp., C. novagracilis, n. sp., C. paucispinosa n. sp. and C. profunda n. sp. In addition, Chaetozone gayheadia Hartman, 1965 is redescribed based on type-material and additional collections and transferred to the genus Chaetocirratulus. Chaetozone benthaliana McIntosh, 1985 is designated a species inquirendum because it was described from a posterior fragment that cannot be confirmed as belonging to any known cirratulid genus or species. Updated descriptions and new records are provided for Chaetozone anasima, C. diodonta, and C. hystricosa all originally described by Doner Blake (2006).

New species and records of Caulleriella (Annelida, Cirratulidae) from shelf and slope depths of the Western North Atlantic Ocean.

Six species of Caulleriella (Cirratulidae), four new to science, are reported from continental shelf and slope depths of the western North Atlantic. The majority of new material was collected as part of deep-water reconnaissance and monitoring surveys along the U.S. Atlantic coast from New England to the Carolinas that were intended to understand the potential impacts of oil and gas exploration in poorly known offshore environments. Additional materials from shallow water and shelf habitats off New England and New York as part of other projects are also included. New species include: Caulleriella filiformia n. sp., C. nobska n. sp., C. pintada n. sp., and C. rodmani n. sp. In addition, new records and comments are provided for C. venefica Doner Blake, 2016 a widespread shelf species and C. sp., a potential new species represented by a few specimens from rocky nearshore New England habitats. The latter may be related to the enigmatic C. fragilis (Leidy, 1855). A review of known deep-water species of Caulleriella is provided.

New species and records of Orbiniidae (Annelida, Polychaeta) from continental shelf and slope depths of the Western North Atlantic Ocean.

Twenty-four species of Orbiniidae, 12 new to science, are reported from continental shelf and slope (deep-sea) habitats of the western North Atlantic. The majority of new material was collected during reconnaissance and monitoring surveys along the entire U.S. Atlantic coast from New England to the Carolinas that were intended to understand the potential impacts of oil and gas exploration in poorly known offshore environments. Additional materials from shallow water and shelf habitats off New England and New York as part of other projects are also included. New collections of Califia schmitti (Pettibone, 1957), Leitoscoloplos acutus (Verrill, 1873), L. fragilis (Verrill, 1873), L. obovatus Mackie, 1987, L. robustus (Verrill, 1873), Scoloplos intermedius (Hartman, 1965), Orbinia swani (Pettibone, 1957), Phylo felix (Kinberg, 1866), P. norvegicus (Sars, 1872), P. ornatus (Verrill, 1873), and Questa trifurcata (Hobson, 1970) provide additional morphological details, variability, and extended geographic and bathymetric distributions of previously known species. New species include Leitoscoloplos pustulus n. sp., Scoloplos papillatus n. sp., S. pettiboneae n. sp., S. pseudoarmiger n. sp., S. verrilli n. sp., Leodamas cuneatus n. sp., L. mucronatus n. sp., L. notoaciculatus n. sp., Phylo paraornatus n. sp., Orbiniella acsara n. sp., O. armata n. sp., and O. mimica n. sp. Juveniles of some species of Leitoscoloplos and Scoloplos were found to resemble known species of the meiofaunal orbiniid genus Schroederella Laubier, 1962. As such, S. berkeleyi Laubier, 1971 is referred to synonymy with Leitoscoloplos acutus. More importantly, the genus Schroederella was found to be pre-occupied by Schroederella Enderlein, 1921 in the Insecta, Diptera, family Helomyzidae. Gesaschroederella nomen nov. is therefore proposed as a replacement name for the polychaete homonym.

Annelids of the eastern Australian abyss collected by the 2017 RV 'Investigator' voyage.

In Australia, the deep-water (bathyal and abyssal) benthic invertebrate fauna is poorly known in comparison with that of shallow (subtidal and shelf) habitats. Benthic fauna from the deep eastern Australian margin was sampled systematically for the first time during 2017 RV 'Investigator' voyage 'Sampling the Abyss'. Box core, Brenke sledge, and beam trawl samples were collected at one-degree intervals from Tasmania, 42°S, to southern Queensland, 24°S, from 900 to 4800 m depth. Annelids collected were identified by taxonomic experts on individual families around the world. A complete list of all identified species is presented, accompanied with brief morphological diagnoses, taxonomic remarks, and colour images. A total of more than 6000 annelid specimens consisting of 50 families (47 Polychaeta, one Echiura, two Sipuncula) and 214 species were recovered. Twenty-seven species were given valid names, 45 were assigned the qualifier cf., 87 the qualifier sp., and 55 species were considered new to science. Geographical ranges of 16 morphospecies extended along the eastern Australian margin to the Great Australian Bight, South Australia; however, these ranges need to be confirmed with genetic data. This work providing critical baseline biodiversity data on an important group of benthic invertebrates from a virtually unknown region of the world's ocean will act as a springboard for future taxonomic and biogeographic studies in the area.

New species and records of deep-water Orbiniidae (Annelida, Polychaeta) from the Eastern Pacific continental slope, abyssal Pacific Ocean, and the South China Sea.

Eighteen species of Orbiniidae, 15 new to science, are reported from deep-sea habitats in the Pacific Ocean and the South China Sea. The collection includes specimens from continental slope and abyssal soft sediments as well as hydrothermal vent and methane seep sites. New collections of Califia calida Hartman, 1957, Naineris uncinata Hartman, 1957, and Phylo nudus (Moore, 1911) allow redescription and new distributional records of these species to be documented. Five species of Leitoscoloplos: L., cliffordi n. sp., L. gordaensis n sp., L. lunulus n. sp., L. sahlingi n. sp., and L. williamsae n. sp. are described together with a new species of Berkeleyia, B. lelievre n. sp., two new species of Scoloplos: S. californiensis n. sp. and S. sparsaciculus n. sp., and a new species of Leodamas, L. bathyalis n. sp. In addition, six new species of Orbiniella are described: O. abyssalis n. sp., O. eugeneruffi n. sp., O. grasslei n. sp., O. longilobata n. sp., O. rugosa n. sp., and O. tumida n. sp.

New Species of Cirratulidae (Annelida, Polychaeta) from the Caribbean Sea.

Fifteen species in seven genera of Cirratulidae are reported from shallow-water collections in the Caribbean Sea primarily as part of the Caribbean I expedition of the research vessel Alpha Helix in 1977 and smaller separate collections from Panama and Venezuela. Thirteen species, all bitentaculates, are new to science. New species include Aphelochaeta caribbeanensis n. sp.; six species of Caulleriella: C. angusticrista n. sp., C. convexacapa n. sp., C. microbidentata n. sp., C. parapicula n. sp., C. parvinasa n. sp., and C. quadrata n. sp.; Chaetozone dossena n. sp.; three species of Kirkegaardia: K. filiformis n. sp., K. panamaensis n. sp., and K. playita n. sp.; and two species of Dodecaceria: D. alphahelixae n. sp. and D. dibranchiata n. sp. Additionally, two multitentaculate cirratulids, Cirriformia sp. from Panama and Timarete punctata (Grube, 1859) from Nicaragua are reported.

New species of Cirratulidae (Annelida, Polychaeta) from abyssal depths of the Clarion-Clipperton Fracture Zone, North Equatorial Pacific Ocean.

Abyssal polychaetes of the family Cirratulidae were collected as part of reconnaissance and benthic impact experimental surveys at Clarion-Clipperton Fracture Zone manganese nodule sites in 1984 and 1993-1994. All specimens were collected from the 4500-4900 m depth range. Twelve species of Cirratulidae were identified, of which 11 are new to science. Aphelochaeta abyssalis n. sp., A. clarionensis n. sp., A. clippertonensis n. sp., A. spargosis n. sp., A. tanyperistomia n. sp., A. wilsoni n. sp., Caulleriella bathytata n. sp., Chaetozone akaina n. sp., C. grasslei n. sp., C. truebloodi n. sp. and Tharyx hessleri n. sp. Most of these species are small deposit-feeding threadlike worms that reside in the upper 5 cm of the sediment and represent a unique assemblage of abyssal taxa.

New species and records of Uncispionidae and Pygospiopsis (Polychaeta, Spionida) from deep water off the east and west coasts of North America, the Gulf of Mexico, the Antarctic Peninsula, and Southeast Asia.

Five new species and one new genus of the obscure spioniform family Uncispionidae are described together with three new species of the rare and unusual spionid genus Pygospiopsis Blake, 1983. All species are from offshore habitats with most from deep-sea continental slope depths. Among the Uncispionidae are the second and third species of the genus Uncopherusa Fauchald Hancock, 1981, collected from off Brunei in the South China Sea and off Louisiana in the Gulf of Mexico; two new species of Uncispio Green, 1982, the third and fourth to be described, from deep water off the U.S. Atlantic coast and the Gulf of Mexico; and a new species of a new genus, Rhamphispio n. gen., from off the U.S. Atlantic coast. All species of Uncispionidae are compared and a key to the known species is presented. The genus Pygospiopsis Blake, 1983, is currently known for only two species: P. dubia (Monro, 1930) from Antarctic and sub-Antarctic waters and P. occipitalis Blake, 1996, from shelf depths off southern California. In the present study, new collections of the type-species P. dubia from the Antarctic Peninsula include post-larvae and juveniles as well as adults, thus permitting documentation of the development of some key adult morphology. Three new species of Pygospiopsis are described from deep water off the U.S. Atlantic and Pacific coasts and from the Antarctic Peninsula. A review of all species of Pygospiopsis suggests that, based on branchial distribution patterns, the closely related Pseudatherospio fauchaldi Lovell, 1994, should be referred to Pygospiopsis, bringing the total known species to six. All of these are compared and contrasted and the generic definition of Pygospiopsis updated. The status of Pygospiopsis within the Spionidae relative to the closely related genus Atherospio Mackie Duff, 1986, is discussed.

Dynamical and Biological Panspermia Constraints Within Multi-planet Exosystems.

As discoveries of multiple planets in the habitable zone of their parent star mount, developing analytical techniques to quantify extrasolar intra-system panspermia will become increasingly important. Here, we provide user-friendly prescriptions that describe the asteroid impact characteristics which would be necessary to transport life both inwards and outwards within these systems within a single framework. Our focus is on projectile generation and delivery and our expressions are algebraic, eliminating the need for the solution of differential equations. We derive a probability distribution function for life-bearing debris to reach a planetary orbit, and describe the survival of micro-organisms during planetary ejection, their journey through interplanetary space, and atmospheric entry.

Bitentaculate Cirratulidae (Annelida, Polychaeta) collected chiefly during cruises of the R/V Anton Bruun, USNS Eltanin, USCG Glacier, R/V Hero, RVIB Nathaniel B. Palmer, and R/V Polarstern from the Southern Ocean, Antarctica, and off Western South America.

Forty-one species in five genera of bitentaculate cirratulids are reported from new collections from South America, the Southern Ocean, and seas around Antarctica. Twenty-seven species are new to science; one new genus is described to deal with some species formerly identified as Chaetozone. New records, synonymies, and new combinations are reported. Previous records are reviewed with type specimens of most species reexamined and redescribed. The sub-Antarctic species Aphelochaeta cincinnata (Ehlers, 1908) does not occur in Antarctica: the numerous published records of this species instead belong to several new species. The types of Tharyx epitocus Monro, 1930, and Tharyx fusiformis Monro, 1939, have spines in posterior setigers and are referred to other genera. Among the 41 species treated in this study, 11 belong to Aphelochaeta, eight are new; eight species belong to Caulleriella, six are new; six species belong to Chaetocirratulus n. gen., three are new; 12 species belong to Chaetozone, seven are new; and four species belong to Tharyx, three are new. Numerous samples come from slope and abyssal depths, expanding our knowledge of the distribution of Southern hemisphere deep-sea cirratulids.

Polychaeta Orbiniidae from Antarctica, the Southern Ocean, the Abyssal Pacific Ocean, and off South America.

The orbiniid polychaetes chiefly from Antarctic and subantarctic seas and off South America are described based on collections of the National Museum of Natural History and new material from surveys conducted by the United States Antarctic Program and other federal and privately funded sources as well as participation in international programs. A total of 44 species of Orbiniidae distributed in 10 genera are reported from the Pacific Ocean and waters off South America and Antarctica. Twenty-one species are new to science; one species is renamed. Berkeleyia heroae n. sp., B. abyssala n. sp., B. weddellia n. sp.; B. hadala n. sp., Leitoscoloplos simplex n. sp., L. plataensis n. sp., L. nasus n. sp., L. eltaninae n. sp., L. phyllobranchus n. sp., L. rankini n. sp., Scoloplos bathytatus n. sp., S. suroestense n. sp., Leodamas hyphalos n. sp., L. maciolekae n. sp., L. perissobranchiatus n. sp., Califia bilamellata n. sp., Orbinia orensanzi n. sp., Naineris antarctica n. sp., N. argentiniensis n. sp., Orbiniella spinosa n. sp., and O. landrumae n. sp. are new to science. A new name, Naineris furcillata, replaces N. chilensis Carrasco, 1977, a junior homonym of N. dendtritica chilensis Hartmann­Schröder, 1965, which is raised to full species status. Leodamas cochleatus (Ehlers, 1900) is removed from synonymy and redescribed. A neotype is established for Leodamas verax Kinberg, 1966, the type species. A general overview of Leodamas species is provided. The Leitoscoloplos kerguelensis (McIntosh, 1885) complex is reviewed and partially revised. Definitions of the genera of the Orbiniidae are updated to conform to recently described taxa. Several new synonymies are proposed following a reexamination of previously described type specimens. The morphological characters used to identify and classify orbiniids are reviewed. The biogeographic and bathymetric distributions of the South American and Southern Ocean orbiniid fauna are reviewed.

Kirkegaardia (Polychaeta, Cirratulidae), new name for Monticellina Laubier, preoccupied in the Rhabdocoela, together with new records and descriptions of eight previously known and sixteen new species from the Atlantic, Pacific, and Southern Oceans.

A new name, Kirkegaardia, is proposed to replace Monticellina Laubier, 1961, a bitentaculate cirratulid polychaete genus, that is a junior homonym of the turbellarian Monticellina Westblad, 1953 (Platyhelminthes, Rhabdocoela). In addition, the opportunity is taken to complete a major revision of the genus including the redescription, revalidation, and separation of three species previously referred to synonymy with K. dorsobranchialis (Kirkegaard, 1959) and five other previously described species. In addition, 16 new species are described from the western North Atlantic, eastern and central Pacific, off western South America, and seas around Antarctica, bringing the total number of species in the genus to 38. Included are two new species of the unusual mud ball worms, first reported as Tharyx luticastellus Jumars, 1975, from southern California deep basins. A review of all 38 species reveals that three distinct species groups may be identified within the genus in addition to 5-6 species that may eventually be referred elsewhere. This review includes a discussion of the taxonomic characters and various newly defined character states that are found among species of Kirkegaardia. Several of these are unique among the Cirratulidae.

Aphelochaeta (Polychaeta: Cirratulidae) from the Pacific coast of Costa Rica, with a description of five new species.

Five new species of bitentaculate Cirratulidae belonging to the genus Aphelochaeta are herein described from the Pacific coast of Costa Rica, all from shallow subtidal depths. Aphelochaeta antelonga sp. nov. is characterized by a long biannulate peristomium and fibrillated capillary setae and is from 11-18 m in the Gulf of Nicoya. Aphelochaeta guimondi sp. nov., with a wide dorsal trough in the thorax and hirsute capillaries (visible using SEM), is described from 11-26 m in the Gulf of Nicoya. Aphelochaeta praeacuta sp. nov., with its first peristomial annulation extending as a dorsal crest over the second annulation and first setiger, was collected from 11-28 m in Bahia Culebra. Aphelochaeta striata sp. nov., collected from 11-28 m in the Gulf of Nicoya, is recognized by its narrow body and the transverse blue stripes across the venter of setigers 5-8 produced with methyl green stain. Aphelochaeta zebra sp. nov., collected from a coral reef in Golfo Dulce, is characterized by its expanded posterior end and the darkly staining intersegmental regions using methyl green stain. Additionally, A. glandaria Blake, 1996, a species reportedly with a widespread geographic distribution (Blake, 1996), was also encountered subtidally from the Gulf of Nicoya and Golfo Dulce.

New species of Scalibregmatidae (Annelida, Polychaeta) from the East Antarctic Peninsula including a description of the ecology and post-larval development of species of Scalibregma and Oligobregma.

A large collection of scalibregmatid polychaetes from the east Antarctic Peninsula in May 2000 has yielded specimens of three new species of Scalibregma, Pseudoscalibregma, and Oligobregma. The new species of Scalibregma is represented by more than 400 specimens that include post-larval and juvenile forms which, for the first time, provide data on the sequence of development of key characters of a scalibregmatid. These data demonstrate that taxonomic characters including the form of the prostomium and presence of branchiae develop late in ontogeny and that small specimens cannot be reliably referred to a species or genus without a growth sequence. Juvenile morphology is also presented for the new species of Oligobregma. The new species of Scalibregma is compared with five northern hemisphere species and differs in details of the peristomium, upper and lower lips of the mouth, dorsal and ventral cirri, and nature of the short spinous setae of setiger 1. The new species of Pseudoscalibregma is unique in the nature of asymmetrical ventral cirri of posterior setigers. The new species of Oligobregma has large acicular spines in both noto- and neuropodia and these are present in juveniles. However, the final adult configuration of the prostomium is not evident until late in development. The taxonomic significance of the timing of development of post-larval and juvenile morphology elucidated in this study is discussed in relation to the validity of certain taxa and the current system of genera used in the family.

Redescription of Tharyx killariensis (Southern) from Ireland and description of two new species of Tharyx from the Kattegat, Sweden (Polychaeta, Cirratulidae).

Two new species of the cirratulid genus Tharyx are reported from shallow waters in the Kattegat inshore Sweden. In addition, the lectotype of Tharyx killariensis (Southern, 1914) is redescribed resulting in a revised concept of the noto- and neuropodial acicular spines of posterior parapodia for that species. These spines were originally reported as bidentate crotchets with sharply pointed teeth; in reality the spines have blunt, knob-shaped tips, typical of several other species of Tharyx. Both of the new species are atypical for the genus Tharyx. T. maryae n. sp. has an expanded posterior end more typical of the genus Aphelochaeta, but otherwise shares characters of Tharyx. T. robustus n. sp. has a body shape that is consistently broad and dorsoventrally flattened throughout, rather than elongate and narrow as in other species of the genus. Both of the new species, however, have short, blunt-tipped spines in far posterior parapodia. With the addition of the two new species, the genus Tharyx now includes 11 species that are compared and contrasted. Morphology that defines and characterizes species of Tharyx is reviewed.

The Orbiniidae (Annelida: Polychaeta) of Pacific Costa Rica.

Seven species of Orbiniidae are described from the Pacific coast of Costa Rica including two new species. Leodamas hamatus n. sp., a commonly occurring species on the coast of Pacific Costa Rica, is described from 11‒18 m in the Gulf of Nicoya and Bahia Culebra. This species is unusual in that the neuropodial uncini differ morphologically from anterior to posterior in the thorax. Scoloplos cryptospinigerus n. sp. is described from 18-22 m in the Gulf of Nicoya and has only a few short, toothed spines amidst numerous capillary setae in most of the thoracic neuropodia. This arrangement of thoracic neurosetae is unusual and has been seen only in one other described species of Scoloplos from Australia.

New species of Chaetozone and Tharyx (Polychaeta: Cirratulidae) from the Alaskan and Canadian Arctic and the Northeastern Pacific, including a description of the lectotype of Chaetozone setosa Malmgren from Spitsbergen in the Norwegian Arctic.

Eight new species of cirratulid polychaetes of the genus Chaetozone from the Alaskan (Beaufort Sea) and Canadian Arctic (Baffin Island, Baffin Bay, Labrador, Hudson Strait, and Hudson Bay) and the Northeastern Pacific are reported together with two new species of Tharyx from the Alaskan Beaufort Sea and the Strait of Juan de Fuca. The new species of Chaetozone and Tharyx are compared with related species; distinct species groups within these genera are discussed. A redescription of C. setosa Malmgren, 1867, the type species of the genus from Spitsbergen, based on a lectotype and associated paralectotypes designated by the late Dr. Mary E. Petersen is presented. A review of characters important in the taxonomy of the genera Chaetozone and Tharyx is presented. A key to species of Chaetozone from the Northeastern Pacific and North American Arctic is provided.

Cryptic species of Archinome (Annelida: Amphinomida) from vents and seeps.

Since its description from the Galapagos Rift in the mid-1980s, Archinome rosacea has been recorded at hydrothermal vents in the Pacific, Atlantic and Indian Oceans. Only recently was a second species described from the Pacific Antarctic Ridge. We inferred the identities and evolutionary relationships of Archinome representatives sampled from across the hydrothermal vent range of the genus, which is now extended to cold methane seeps. Species delimitation using mitochondrial cytochrome c oxidase subunit I (COI) recovered up to six lineages, whereas concatenated datasets (COI, 16S, 28S and ITS1) supported only four or five of these as clades. Morphological approaches alone were inconclusive to verify the identities of species owing to the lack of discrete diagnostic characters. We recognize five Archinome species, with three that are new to science. The new species, designated based on molecular evidence alone, include: Archinome levinae n. sp., which occurs at both vents and seeps in the east Pacific, Archinome tethyana n. sp., which inhabits Atlantic vents and Archinome jasoni n. sp., also present in the Atlantic, and whose distribution extends to the Indian and southwest Pacific Oceans. Biogeographic connections between vents and seeps are highlighted, as are potential evolutionary links among populations from vent fields located in the east Pacific and Atlantic Oceans, and Atlantic and Indian Oceans; the latter presented for the first time.

Plan-view photos, benthic grabs, and sediment-profile images: Using complementary techniques to assess response to seafloor disturbance.

A monitoring survey was conducted in July 2005 at the Rhode Island Sound Disposal Site (RISDS) as part of the Disposal Area Monitoring System (DAMOS) program. The survey included the collection of sediment-profile and plan-view images, and benthic biology grabs. Each of these techniques provides a different, yet complementary perspective on benthic community conditions. These complementary techniques aided in the assessment of the benthic recovery process within RISDS following the placement of dredged material from the Providence River and Harbor Maintenance Dredging Project (PRHMDP). Based on observed patterns of physical, chemical, and biological responses of seafloor environments to dredged material disposal activity it was expected that the benthic community within RISDS would be in an intermediate phase of recolonization (Stage II). Results of the 2005 RISDS survey indicated that in the six months since disposal activities at RISDS had concluded, the biological community at RISDS was recovering relatively rapidly and Stages II and III infauna were present throughout the region.