New and little-known species of Didemnidae (Ascidiacea,Tunicata) from Australia (part I)

Continuing examination of colonial ascidians in museum collections is revealing further diversity in the family Didemnidae, which abounds in the tropical Indo-West Pacific and around the Australian continent (Kott, 2001). From the present work, it is apparent that much remains to be learnt about this fauna. Of the 45 species discussed in this paper, 16 are new. Larvae are described for the first time for Polysyncraton pedunculatum Kott, 2001 and P. rica Kott, 2001. Amongst the synonymy established in this paper Didemnoides tropicum Sluiter, 1909 is found to be a junior synonym of Lissoclinum patella (Gottschaldt, 1898) and Trididemnum vermiforme Kott, 2001 a junior synonym of T. nobile Kott, 2001. Didemnum nekozita Tokioka, 1967 is found to be a valid species distinct from Polysyncraton cuculliferum (Sluiter, 1909). Prolific replication rates, rapid colony growth, flexibility in growth form and a viviparous habit result in convergence tending to small zooid size, and similar large, increasingly complex colonies found in this family contribute to species diversity around the whole of the Australian continent.     

Taxonomic revision of Ascidiacea (Tunicata) from the upper continental slope off north-western Australia

A collection of ascidians from 100–1000 m deep off the north-western coast of Australia has yielded 19 species, including one new, two possibly endemic to the north-western coast of Australia, four well-known Indo-west Pacific tropical species and 12 species known from the deeper waters of the western Pacific, of which 11 had not previously been recorded from off the western Australian coast or from other parts of the Indian Ocean. A third of these 12 species displays adaptations for a reduction in filter-feeding capacity, as do other known species from deeper slope and abyssal habitats. Nevertheless a connection with fauna of deep ocean basins of the Indian Ocean is not apparent at this stage. The full range of characters associated with species, genera and families are discussed, and those contributing to the identification of immature or mutilated specimens, as well as those relevant to an assessment of phylogenetic relationships, are emphasized.     

The colonial ascidian fauna of Fiordland,New Zealand,with a description of two new species

A total of 17 species from the families Styelidae, Polyclinidae, Polycitoridae, Pseudodistomidae, Ritterellidae and Didemnidae are described for the first time in collections from remote fiords with steep-sided walls, high rainfall and high tidal flow on the south-west coast of New Zealand. The Fiordland ascidian assemblages are composed of endemic species, species with trans-Tasman affinities, species found in southern New Zealand and species found New Zealand wide, some of which have global distributions. Two Australian native species, Diplosoma velatum Kott, 2001 and Didemnum jucundum Kott, 2001 from South Australia are new records to New Zealand and a further eight species remain undescribed. Two new colonial ascidians Aplidium coronum sp. nov. and Trididemnum shawi sp. nov. are described in this paper.

http://zoobank.org/urn:lsid:zoobank.org:pub:5ADC2C9D-28AC-4348-8B4D-F26-2A43DEA66     

Novel Australian Polyzoinae (Styelidae,Tunicata)

Species in the colonial subfamily Polyzoinae demonstrate a range of colonial organisations. Colony form appears to be significant at species level but not to have a phylogenetic significance at genus level, species in both speciose genera Polyandrocarpa and Stolonica having colonies either of separate zooids joined by basal stolons or they have completely embedded zooids. Polyandrocarpa and Oculinaria have characters that indicate a close affinity with solitary styelinid genera Polycarpa and Cnemidocarpa, respectively, and suggest that the subfamily is polyphyletic. Stolonica and other genera in the Polyzoinae, in which zooids and body organs are small and simplified, also appear to be polyphyletic assemblages of taxa but their relationships are masked by parallel evolution and convergence associated with replication and colony development. Previously overlooked in the siphonal linings of Oculinaria australis are overlapping spines possibly analagous with the rounded scales (see Kott 1985 Kott, P. 1985. The Australian Ascidiacea Pt 1, Phlebobranchia and Stolidobranchia.. Memoirs of the Queensland Museum, 23: 1–440.  [Google Scholar]) in siphons of Stolonica diptycha (Hartmeyer, 1919 Hartmeyer, R. 1919. Ascidien. In: Results of Dr E. Mjöberg's Swedish scientific expeditions to Australia 1910–13.. Kungliga Svenska Vetenskapsakademiens Handlingar, 60(4): 1–150.  [Google Scholar]). Similar armature appears to be significant at species level in Pyuridae and occasionally Styelidae and it may be further evidence of polyphyly in Polyzoinae. One of the seven species reported (Stolonica vermiculata sp. nov. from Lord Howe I.) is new; one (Oculinaria australis from a range of locations around the southern half of the Australian continent) is recorded often; and five (Polyandrocarpa colemani known only from the Queensland–New South Wales border, P. colligata, Stolonica styeliformis and S. duploplicata all from the tropical western Pacific and Botryllocarpa elongata from Tasmania) are seldom recorded.     

A primitive representative of the Parabathynellidae (Bathynellacea,Syncarida) from the Yilgarn Craton of Western Australia

Billibathynella humphreysi gen. et sp. nov. is described from calcrete aquifers located in the Yilgarn Craton of north‐western Australia. This is the first parabathynellid known from the Australian Precambrian shields, which have never been inundated by the sea. A comparison of the primitive species so far known from Australia and other continents points to the new species as being the most primitive among the parabathynellids. It further suggests that the new genus has an affinity to Notobathynella Schminke, but differs in having a six‐segmented antenna and a large epipod of the male thoracopod VIII. An attempt to relate the primitiveness of the new species to the historiogeological characteristics of the region has led to the conclusion that the recent parabathynellids could have emerged from freshwater epigean ancestors. It is further assumed that the transition of their ancestors to groundwaters happened in Notogaea.     

New species of Brodskius,Rythabis, and Omorius (Crustacea: Calanoida) from deep Antarctic waters

Three new species of rare benthopelagic clausocalanoidean genera with sensory setae on the maxilla are described from female specimens collected during the German Antarctic expeditions ANDEEP I–III in 2002 and 2005, mainly from abyssal depths close to the sea bed. Brodskius abyssalis sp. nov. differs from congeners by the lack of rostral filaments, two setae on the second segment of antenna exopod, thread‐like tips of maxillary worm‐like sensory setae, and the length of spines of P5 exopod. Rythabis assymmetrica sp. nov. is distinguished from other species in the genus by asymmetrical posterior corners of the prosome, the shape of spermathecae, and setal numbers on the maxillulary distal basal endite plus endopod. Omorius curvispinus sp. nov. is characterized by strongly curved setae of the maxillipedal syncoxa, a comparatively long seta on the basis of antenna, a slightly swollen genital double‐somite, and the shape of spermathecae. The genera Brodskius, Omorius, and Rythabis are recorded for the first time from the southern hemisphere.     

Some benthic Tunicata from the southern Indo-Pacific Ocean

Forty one species of benthic Tunicata are recorded in the material collected from 87–5760m from the Coral Sea, Tasman Sea and the waters south of Australia and New Zealand, up to 65°S. Several species, recorded for the first time from the region, were previously known from the central and western Indian Ocean. Seven new species are described.     

The carcinofauna found in stomach contents of the flying gurnard (Dactylopterus volitans) on the continental shelf of the Campos Basin,Brazil

A total of 3109 crustaceans belonging to 50 taxa distributed in 42 families were found in 117 analysed stomachs of flying gurnard (Dactylopterus volitans). Samples were obtained in April 2008 by the R/V Gyre using a bottom trawl towed in 12 stations at 14–100 m depth on the continental shelf of the Campos Basin, Brazil. The carcinofauna was analysed and the order Calanoida (Copepoda) found to be the most important item in terms of relative abundance and frequency of occurrence, followed by the order Amphipoda (Peracarida), the infraorder Brachyura (Decapoda), the order Stomatopoda and the subclass Myodocopa (Ostracoda). In the order Calanoida, the species Pontellopsis cf. villosa (Pontellidae) represented 98.04% of total crustacean abundance. The diet of Dactylopterus volitans varied according to fish size, with higher diversity of Crustacea at smaller size classes, decreasing in larger fishes. A similar pattern regarding depth was obtained, with greater diversity of taxa in gurnard stomachs caught at shallower depths. Flying gurnard is considered a generalized carnivore of invertebrates, eating mobile macrobenthic organisms, such as crustaceans, and its diet varies with its life stage, without any specific group as its main food source.     

Colonial ascidians from the Foveaux Strait region of New Zealand

Colonial ascidians collected from wharf piles and natural substrata from Bluff Harbour and Stewart Island in the South Island of New Zealand are described in this paper. Two species, Lissoclinum violaceum sp. nov. and Didemnum marineae sp. nov. are new to science and described for the first time. The ascidian fauna in this region is a mixed assemblage of southern species, species with a New Zealand-wide distribution, and two species with trans-Tasman affinities.

www.zoobank.org/urn:lsid:zoobank.org:pub:37DC0D4B-8FB9-4F1D-A5A0-E9CAB3203447     

A new genus and six new species of the Parabathynellidae (Bathynellacea,Syncarida) from the Kimberley region,Western Australia

Six new species of a new genus of the Parabathynellidae are described from the Kimberley Region, Western Australia. The erection of the new genus, Kimberleybathynella gen. nov., is based on the two‐segmented antenna, the partial fusion of the second and third segments of the maxilla, and the setal condition of the uropodal exopodite, where the outer seta is longer than the inner one. The one‐segmented exopodite of thoracopods I–VII and hemispherical form of male thoracopod VIII suggest the close relationship of Kimberleybathynella to the genus Atopobathynella.     

The peracarid epifauna associated with the ascidian Pyura chilensis (Molina, 1782) (Ascidiacea: Pyuridae)

Epifaunal peracarids inhabit a variety of biogenic substrata, including ascidians. Herein we examined the peracarid fauna living on the tunica of the sublittoral ascidian Pyura chilensis growing in offshore and nearshore conditions in Bahía San Vicente, Chile. From a total of 38 samples we collected 17 species of Amphipoda, five Isopoda and two Tanaidacea. The similarity between the sites was high (73.8%, Sorensen's index). Species diversity (H') was 2.8 and 2.6, evenness (J) was 0.7 and 0.6 at the offshore and nearshore site, respectively. Both species and individual number increased significantly with the size (volume) of the ascidian samples, and these relationships did not differ between the sites. Many species, in particular the most abundant ones, occurred at both sites, but some species were restricted either to the offshore (three species) or to the nearshore site (seven species). Amphipods and tanaids were the most abundant taxa at both sites. The peracarid fauna at both sites was dominated by suspension-feeding peracarids (>80% of the individuals), which utilize the ascidians primarily as shelter, feeding on allochthonous material, i.e. not originating from the ascidians. It is suggested that the high percentage of suspension-feeding species among the epifaunal peracarids is due to the fact that ascidians settle and grow at sites that provide optimal feeding conditions for these organisms.     

Two new Sarsiellinae (Ostracoda: Myodocopa) from Ningaloo Reef (Western Australia), with a cladistic analysis of the subfamily and keys to genera

Two new Sarsiellinae from Ningaloo Reef, Spinacopia ningalooi sp. nov., and Metasarsiella caleyi sp. nov. are described. Spinacopia ningalooi is the first representative of the genus collected from a coral reef. It differs from the other species by its odd looking posterior infold. Metasarsiella caleyi sp. nov. is the first species of the genus reported from Australia. Keys to species of Spinacopia Kornicker, 1969 Kornicker, LS. 1969. Morphology, Ontogeny, and Intraspecific Variation of Spinacopia, a new genus of myodocopid ostracod (Sarsiellidae). Smith Contr Zool., 8: 50 [Google Scholar] and Metasarsiella Kornicker, 1991 Kornicker, LS. 1991. Myodocopid Ostracoda from Enewetak and Bikini Atolls. Smith Contr Zool., 505: 140 [Google Scholar], and to all the genera of Sarsiellinae are given here, together with an inventory of all the species and information on their distributions and biology. The results of two cladistic analyses (with unweighted and with weighted characters) of the subfamily based on 138 species and 34 morphological characters are presented. The first analysis resulted in seven equally parsimonious trees and the second in just one. The majority rule of the first group of trees and the tree from the second analysis are presented here.     

Notes on astogeny of some Petraliellidae (Bryozoa) from Australia

Members of the bryozoan family Petraliellidae share the capacity to develop basal rhizoids, which anchor the unilaminar, semi-repent parts of the colonies above the substratum, and enable them to overgrow other, competing sessile forms. Little is known of the larval behaviour and settlement, or the early astogeny of species. Ancestrulate colonies of the Australian Tertiary lunulitiform species Smittia biincisa are referred to the genus Riscodopa, and together with Riscodopa paucipora sp. nov. are described and compared with the Recent species R. cotyla and R. parva from New Zealand, and with R. hyalina sp. nov. from New South Wales, Australia. All the Recent species are known to develop basal rhizoids, and an early astogeny similar to that of many other small, rooted bryozoans, comprising the post-metamorphosis development of a binary complex, including rhizoid and feeding elements, is inferred for Riscodopa. Observations on living Hippopetraliella magna from Queensland suggest that both the ancestrular morphology and early astogeny show a capacity for semi-repent growth, even though they do not include rhizoid development. Larvae metamorphose without direct attachment, and the ancestrula develops elongated, partially calcified supporting processes, which raise the early stages of growth above the substratum. A similar kind of ancestrula has been found in preserved specimens of Mucropetraliella ellerii.     

Description of a new genus and species of the subfamily Arcoscalpellinae Zevina, 1978 (Cirripedia: Thoracica: Scalpellidae) from deep waters of the South China Sea

A deep-sea pedunculate barnacle of the family Scalpellidae, subfamily Arcoscalpellinae, collected from deep waters of the South China Sea is studied. Sinoscalpellum gen. nov. is erected to accommodate Sinoscalpellum sinensis sp. nov. The new genus differs from the other genera by the inframedian latus narrow and long, umbo at basi-rostral angle and protruded to below rostrum. A key to genera of the subfamily Arcoscalpellinae is provided.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:061A3277-012E-4808-B7BA-3180CF910CD7