A new anglerfish from eastern Australia and New Caledonia (Lophiiformes: Chaunacidae: Chaunacops), with new data and submersible observation of Chaunacops melanostomus

A new deep‐sea anglerfish of the genus Chaunacops is described based on three specimens collected from eastern Australia and New Caledonia. It differs from its congeners in having fine dermal spinules, mixed with simple and bifurcate ones, densely covering the body, four neuromasts on the pectoral series of the lateral line and a combination of other characteristics. Data for Chaunacops melanostomus based on 31 specimens newly collected from Western Australia are provided. An underwater observation of C. melanostomus made by a remotely operated vehicle is also provided.     

Systematic review of the genus <Emphasis Type="Italic">Bothrocara</Emphasis> Bean 1890 (Teleostei: Zoarcidae)

The systematics of the eelpout genus Bothrocara Bean 1890 is reviewed on the basis of 941 specimens. Eight mostly eurybathic, demersal species are recognized, distributed mainly along the continental slopes of the North and South Pacific oceans, with one species entering the South Atlantic. Distributions are: B. brunneum ranges from the Sea of Okhotsk to the Gulf of Panama at depths of 199–1,829 m; B. elongatum ranges from the Gulf of Panama to Chile at depths of 720–1,866 m; B. hollandi ranges from the Sea of Japan to the southeastern Bering Sea at depths of 150–1,980 m; B. molle ranges from the western Bering Sea to the South Atlantic at depths of 106–2,688 m; B. nyx is known only from the eastern Bering Sea at depths of 790–1,508 m; B. pusillum ranges from the northern Bering Sea to British Columbia, Canada, at depths of 55–642 m; B. tanakae is found along the northern coasts of Honshu and Hokkaido islands, Japan, at depths of 274–892 m; B. zestum ranges from the Izu Islands, Japan, and central Honshu, Japan, to the Gulf of Alaska at depths of 199–1,620 m (an unidentifiable specimen from off Taiwan may be B. zestum). The species are distinguished from one another mainly on the basis of head pore patterns, gill raker morphology, coloration and various meristic and morphometric values. A determination key to the species is provided.     

Phenacoscorpius longicaudalis,a new species of scorpionfish (Teleostei: Scorpaenidae) from Western Australia,with first records of Phenacoscorpius adenensis from the southeastern Indian Ocean

Ichthyological Research - Phenacoscorpius longicaudalis sp. nov. is described from 19 specimens collected in depths of 228–990&nbsp;m off Western Australia, eastern Indian Ocean. The new...     

ZONATION OF DEEP WATER BENTHIC ALGAE IN THE GULF OF MAINE1

Algal community structure is described for a deep-water rock pinnacle in the Gulf of Maine. Three depth zones of algal dominance were apparent consisting of 1) leathery macrophytes (to 40 m), 2) foliose red algae (to 50 m) and 3) crustose algae (fleshy crusts to 55 m and coralline crusts to 63 m). Microscopic filamentous and erect calcareous algae were also present but inconspicuous. Upright macroscopic filamentous and thin sheet-like forms were not observed on the pinnacle. Sea anemones (Metridium senile) dominated some vertical faces and abrupt prominences in the shallowest regions of the pinnacle (to 24 m) and locally appeared to set the upper vertical limits of kelp and possibly foliose reds. Laminaria sp. formed an open park-like canopy from 24 to 30 m whereas Agarum cribrosum, the deepest kelp, grew as isolated individuals to 40 m. Peyssonnelia sp. and Leptophytum laeve were the deepest occurring fleshy (to 55 m) and calcareous crusts (to 63 m), respectively. The occurrence of these algae at record depths for the Gulf of Maine and for cold water marine environments may be the result of an absence of large herbivores and the high productivity potential of the benthos in these relatively clear waters. By compiling data on depth distribution patterns world-wide, it is evident that the three zone structure of algal morphologies observed in the Gulf of Maine is a global phenomenon.     

Vertical distributions and relations of euphausiid populations off Elephant Island,March 1984

Summary Distributional relationships are described for post-larval and larval Euphausia superba and Thysanoessa sp. (probably macrura) and post-larval Euphausia frigida collected in 0–70/80 m and 0–175/200 m depth ranges with a MOCNESS sampler north of Elephant Island (61°S, 55°W) during 17–23 March 1984. Larval E. superba (predominantly calyptopes stage 2 and 3) were rare shallower than 80 m at night. Day catches of post-larval E. suberba were small and night catches were primarily near the top of the thermocline above 50 m depth. Thysanoessa sp. occurred throughout the 0–200 m depth range and was abundant in the upper 80 m both night and day. E. frigida migrated to the upper 80 m at night from deeper day depths. Larval stages of E. superba and bost-larval stages of all three species demonstrated independent and variable vertical distribution patterns both night and day. Changes in E. superba abundance and distributional patterns could to a certain extent be associated with observed environmental changes. An increase in larval and decrease in post-larval E. superba abundances between 0–80 m was associated with an intrusion of cold water at depth. At night, vertically restricted concentrations of post-larval E. superba were associated with shallow mixed layer depths, and a significant vertical separation of developmental stages and size categories was observed only during periods of stratification in the upper 80 m. Fluctuations in the distribution and abundance of Thysanoessa sp. and distribution of E. frigida did not appear to be influenced by physical parameters within the upper 80 m. Within the 0–80 m depth range, the distributions of these two species differed from each other and from E. superba and showed large tow to tow variability that could not be related to physical parameters in the upper water column.     

PHOTOPHYSIOLOGY OF A TURF ALGAL COMMUNITY: INTEGRATED RESPONSES TO AMBIENT LIGHT AND STANDING BIOMASS1

This study investigated the variation in the relationship between photosynthesis and ambient light (P‐E curves) for turf algal communities on a temperate reef off the coast of South Australia, analyzing the integrated effects of ambient light and standing biomass. The photophysiology of turfs was studied in situ on a seasonal basis, examining algal communities growing on artificial substrate (plates) at depths of 4 m and 10 m. P‐E curves and estimates for the photokinetic parameters (P_m, R_d, α, E_k, and E_c) were obtained through oxygen evolution methods, using an automated underwater respirometer. Photoacclimation responses to changes in ambient light were strongly affected by the biomass of the community. P_m showed an inverse relationship to standing biomass, irrespective of depth and season, which was considered to be a response to self‐shading and boundary layer effects. Biomass effects imposed a high variance on estimates for all photosynthetic parameters, overshadowing differences observed for season and depth. Biomass also affected photoinhibition on turf communities, where significant afternoon depression of photosynthesis was observed in sparse turf patches when compared to denser patches. High areal productivity rates were maintained across all seasons with a significant decrease only being observed during winter.     

New species and records of Pelycidion P. Fischer in de Folin & Périer, 1873 (Gastropoda: Pelycidiidae) from temperate Australia

Four new species of Pelycidion P. Fischer in de Folin & Périer, 1873 are described from temperate Australia on the basis of shells: Pelycidion eukyrtos n. sp. from central Victoria, P. caperovertex n. sp. and P. kratycylindros n. sp. from southwest Australia and P. meizonarchei n. sp. from southern Tasmania. Two additional congeneric specimens are known from the region and discussed; one of these, from the Tasman Sea, is illustrated and likely represents a new species. Collectively, these specimens are the first members of the genus and family to be recorded from temperate Australia. A brief overview of the described species of Pelycidion is given.     

Etheliaceae fam. nov. (Gigartinales,Rhodophyta), with a clarification of the generitype of Ethelia and the addition of six novel species from warm waters

Based upon COI‐5P, LSU rDNA, and rbcL sequence data and morphological characteristics, six new members of the noncalcified crustose genus of red algae Ethelia are described in a new family, Etheliaceae (Gigartinales), sister to the recently described Ptilocladiopsidaceae. The novel species are described from subtropical to tropical Atlantic and Indo‐Pacific Ocean basins; E. mucronata sp. nov. and E. denizotii sp. nov. from southern and northern Western Australia respectively, E. wilcei sp. nov. from the Cocos (Keeling) Islands of Australia, E. suluensis sp. nov. from the Philippines, E. umbricola sp. nov. from Bermuda and E. kraftii sp. nov. from Lord Howe Island, Australia. The generitype, Ethelia biradiata, originally reported from the Seychelles, Indian Ocean, is added to the Western Australian flora.     

Three species of Pycnadenoides Yamaguti, 1938 (Digenea: Opecoelidae), including two new species from temperate marine fishes of Australia

Pycnadenoides pagrosomi Yamaguti, 1938 and P. reversati n. sp. from Pagrus auratus (Sparidae) and P. invenustus n. sp. from Nemadactylus valenciennesi (Cheilodactylidae) are described from the temperate marine waters off south-west Western Australia and south-east Queensland. The difference in the anterior extent of the vitelline follicles observed in P. reversati n. sp. recovered from off south-east Queensland waters and the material from off Western Australia is discussed. P. reversati n. sp. is distinguished from P. pagrosomi mainly in the position of the genital pore and in the arrangement of the testes, and from P. invenustus n. sp. in the posterior extent of the cirrus-sac. P. reversati belongs to the group of species with a short cirrus-sac and P. invenustus to the group with the cirrus-sac reaching into the anterior hindbody.     

Studies of the Liagoraceae (rhodophyta) of Western Australia: Gloiotrichus fractalis gen. et sp. nov. and Ganonema helminthaxis sp. nov.

Two new taxa of Liagoraceae (Nemaliales) are described from Western Australia. Gloiotrichus fractalis gen. et sp. nov. has been collected from 3–20 m depths at the Houtman Abrolhos, Western Australia. Plants are calcified, extremely lubricous, and grow to 17 cm in length. Carpogonial branches are straight, 6 or 7 cells in length, arise from the basal or lower cells of cortical fascicles, and are occasionally compound. Branched sterile filaments of narrow elongate cells arise on the lower cells of the carpogonial branch prior to gonimoblast initiation, at first on the basal cells, then on progressively more distal cells. Following presumed fertilisation the carpogonium divides transversely, with both cells giving rise to gonimoblast filaments. The distal cells of the carpogonial branch then begin to fuse, with fusion progressing proximally until most of the cells of the carpogonial branch are included. As fusion extends, the filaments on the carpogonial branch are reduced to the basal 2 or 3 cells. The gonimoblast is compact and bears terminal carposporangia. Spermatangial clusters arise on subterminal cells of the cortex, eventually displacing the terminal cells. The sequence of pre- and post-fertilisation events occurring in the new genus separates it from all others included in the Liagoraceae, although it appears to have close affinities with the uncalcified genus Nemalion. Ganonema helminthaxis sp. nov. was collected from 12 m depths at Rottnest Island, Western Australia. Plants are uncalcified and mucilaginous, the axes consisting of a few (< 10) primary medullary filaments, each cell of which gives rise to a cortical fascicle at alternate forks of the pseudodichotomies borne on successive medullary cells. Subsidiary (adventitious) filaments and rhizoids comprise the bulk of the thallus. Carpogonial branches are straight, (3-)4(-6) cells in length, arise on the basal 1–4 cells of the cortical fascicles, and are frequently compound. Carposporophytes develop from the upper of two daughter cells formed by a transverse division of the fertilised carpogonium. Ascending and descending sterile filaments girdle the carpogonial branch cells and arise mostly on the supporting cell prior to fertilisation. Ganonema helminthaxis is the first completely non-calcified member of the genus, and its reproductive and vegetative morphology supports the recognition of Ganonema as a genus independent from Liagora. Liagora codii Womersley is a southern Australian species displaying features of Ganonema, to which it is transferred.     

Instar distribution and biomass of Chironomidae larvae in Lago El Junco, Isla San Cristobal, the Galápagos

The distribution, abundance and standing crop biomass of chironomid larvae were determined at one-meter depth intervals along three radial transects. Samples were collected by coring soft sediments while diving. Three genera were found in the lake: Chironomus sp. (collector-filtering larvae), Ablabesmyia sp. (predatory larvae) and Goeldichironomus sp. (collector-filtering larvae). Standing crop densities of chironomids, averaged over the entire lake, varied from 30,594 larvae/m² to 11,428 larvae/m² at different depths. No statistically significant zonation in density was found for the two most common taxa, Chironomus sp. (87.8% of specimens) and Ablabesmyia sp. (9.0%), however the deepest zones (>4 m) had the lowest estimated densities. Significant differences in standing crop biomass were detected, with the 6 m depth having greatest biomass. The increase in standing crop biomass was a function of (1) lower frequency of first instars of Chironomus sp. and Ablabesmyia sp. at 6 m (2) higher average larval biomass of both species at 6 m and (3) very significant increase in average biomass of fourth instars of Chironomus sp. at 6 m compared to fourth instars at shallower depths. These results indicate that the lentic chironomids of this isolated oceanic habitat consist of a small number of species that are ecological generalists and tolerant of low oxygen concentrations.     

A new species of the deep-sea fish genusParabrotula (Parabrotulidae) from Sagami Bay with notes on its ecology

Parabrotula tanseimaru sp. nov. (Zoarcoidei: Parabrotulidae) is described from Sagami Bay, central Japan, as the second species of the genus. The new species is readily distinguished from the known species,P. plagiophthalma, by dorsal fin ray counts (44–50 vs. 37–43) and higher total vertebral counts (64–73 vs. 54–64).P. tanseimaru is viviparous, occurring in pseudoceanic meso-/bathypelagic depths and feeding primarily on copepods.     

Three new deep-sea species of Sphaerodoridae (Annelida,Polychaeta) from the eastern tropical South Pacific*

Three sphaerodorid species new to science are described from a manganese nodule area in abyssal depths of around 4150 m in the Peru Basin in the eastern South Pacific. Sphaerodoridium campanulata sp. n. is isolated within the genus, having, apart from spherical macrotubercles, additional dorsal stalked bell-shaped papillae, not previously described. Sphaerodoropsis discolis sp. n. is a species with four rows of dorsal macrotubercles and two pairs of lateral antennae. Sphaerodoropsis translucida sp. n. has six to seven rows of dorsal macrotubercles arrayed in two transverse rows per segment and two pairs of lateral antennae. A brief discussion points to the close relationship between Clavodorum and Sphaerodoridium, and to the present state of Sphaerodoropsis, being inhomogeneous in the characters of the arrangement of the dorsal macrotubercles and the numbers of the lateral antennae. An overview on the latter genus, with an attempt to subdivide it, is given.     

<Emphasis Type="Italic">Melanostigma kharini</Emphasis> sp. nov. (Zoarcidae), a New Species of Pelagic Eelpout from the Ridge of Hercules (Pacific-Antarctic Rise)

A new species Melanostigma kharini sp. n. is described from the underwater Ridge of Hercules (Pacific-Antarctic Rise). The specimens of the new species were collected in the marine expeditions of the Pacific Scientific Research Institute of Fishery and Oceanography (TINRO) (1977?1978) on the Southern Bank at depths between 240 and 780 m. The new species differs from the other species of the genus in an original combination of the characters, in particular, in the structure of the lateral line canals on the head, axial skeleton, and coloration. Vertebral asymmetry and the features of rational (purposive) development of the seismosensory system on the head of Melanostigma are described in detail.     

Revision of the bathyal fish genusHomostolus (Ophidiiformes,Ophidiidae)

The ophidiid fish genusHomostolus is revised on the basis of 44 specimens. Meristic and morphometric characters strongly indicate that the genus as presently known contains a single species,Homostolus acer Smith et Radcliffe, 1913, withHomostolus japonicus Matsubara, 1943, reduced to synonymy. Geographical variations found in certain meristic characters indicate thatH. acer expanded its range from Philippine waters into both northern and southern waters. The species is distributed on deep-sea floors from the Pacific Ocean off central Japan, to the Indian Ocean off northern Western Australia, and to the Tasman Sea off New South Wales, at bathyal depths from about 400 to 700 m.     

Temporal and spatial patterns of water mites in Lake Maarsseveen I

The paper analyses the distribution and seasonal changes in numbers of the water mite fauna of Lake Maarsseveen I. Water mites were collected from 1977 until 1986 by dipnet, underwater light trap, hydraulic lift sampler and by frame net. Fifty-two species belonging to the Hydrachnellae and one to the Halacaridae were sampled. The faunal picture obtained is characteristic of mesotrophic to eutrophic lakes.Arrenurus nobilis. Piona paucipora andP. imminuta can be characterised as lake species. The dominant species in the littoral sand flat areHygrobates nigromaculatus andH. trigonicus, at a depth of 0.5–1 m, andMideopsis orbicularis at depths of 2–7 m.Limnesia maculata is also very common on depths between 2 and 7 m. In early summer, however, they prefer shallow water up to 1 m depth. Some species likeHygrobates nigromaculatus andH. trigonicus were not captured by the underwater light trap. The hydraulic lift sampler gave underestimations of the densisty of certain speciese.g. Hygrobates spp. andLimnesia maculata. Unionicola spp. even can avoid this sampler. Sampling by frame net gave the most realistic data. The highest number of water mites was observed in the littoral sand flat, generally up to 1000 ind. m⁻². The genusHygrobates was represented with an average of 800 adult ind. m⁻² throughout the year, and appeared to be the main invertebrate predator in this habitat.     

Five new species of dicyemid mesozoans (Dicyemida: Dicyemidae) from two Australian cuttlefish species, with comments on dicyemid fauna composition

Five new species of dicyemid mesozoans in two genera are described from two Australian cuttlefish species, Sepia apama Gray (giant Australian cuttlefish) and S. novaehollandiae Hoyle (nova cuttlefish): Dicyema coffinense n. sp. from S. apama collected from Coffin Bay, South Australia (SA), Australia; D. koinonum n. sp. from S. apama and S. novaehollandiae collected from Gulf St Vincent (GSV) and Spencer Gulf (SG), SA, Australia; D. multimegalum n. sp. from S. apama collected from Cronulla and North Bondi, New South Wales, Australia; D. vincentense n. sp. from S. novaehollandiae collected from GSV, SA, Australia; and Dicyemennea spencerense n. sp. from S. novaehollandiae and S. apama collected from SG, SA, Australia. Totals of 51 S. apama and 27 S. novaehollandiae individuals were examined, of which all except for four S. apama were infected by at least one dicyemid species. Dicyemid parasites were also observed in host individuals that were held in tanks for 2–3 months prior to examination, including nematogen-exclusive infections, leading to questions about persistence of dicyemids after host death and the mechanism responsible for the switch between a nematogen phase and a rhombogen phase. Variations in host size, calotte shape and collection locality are explored as predictors of differences in observed composition of the parasite fauna. In particular, dicyemid parasite fauna varied with host collection locality. As these parasites are highly host-species specific, their use as biological tags to assess cephalopod population structure using a combined morphological and molecular approach is discussed. This study increases the number of dicyemid species described from Australian cephalopods from five to ten, and from 117 to 122 species described worldwide.     

The Potential of Bacterial Isolates for Emulsification with a Range of Hydrocarbons

A study was undertaken to investigate the distribution of biosurfactant producing and crude oil degrading bacteria in the oil contaminated environment. This research revealed that hydrocarbon contaminated sites are the potent sources for oil degraders. Among 32 oil degrading bacteria isolated from ten different oil contaminated sites of gasoline and diesel fuel stations, 80% exhibited biosurfactant production. The quantity and emulsification activity of the biosurfactants varied. Pseudomonas sp. DS10‐129 produced a maximum of 7.5 ± 0.4 g/l of biosurfactant with a corresponding reduction in surface tension from 68 mN/m to 29.4 ± 0.7 mN/m at 84 h incubation. The isolates Micrococcus sp. GS2‐22, Bacillus sp. DS6‐86, Corynebacterium sp. GS5‐66, Flavobacterium sp. DS5‐73, Pseudomonas sp. DS10‐129, Pseudomonas sp. DS9‐119 and Acinetobacter sp. DS5‐74 emulsified xylene, benzene, n‐hexane, Bombay High crude oil, kerosene, gasoline, diesel fuel and olive oil. The first five of the above isolates had the highest emulsification activity and crude oil degradation ability and were selected for the preparation of a mixed bacterial consortium, which was also an efficient biosurfactant producing oil emulsifying and degrading culture. During this study, biosurfactant production and emulsification activity were detected in Moraxella sp., Flavobacterium sp. and in a mixed bacterial consortium, which have not been reported before.