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"Gershwin, Lisa-Ann"
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A New Dolphin Species, the Burrunan Dolphin Tursiops australis sp. nov., Endemic to Southern Australian Coastal Waters
Small coastal dolphins endemic to south-eastern Australia have variously been assigned to described species Tursiops truncatus, T. aduncus or T. maugeanus; however the specific affinities of these animals is controversial and have recently been questioned. Historically 'the southern Australian Tursiops' was identified as unique and was formally named Tursiops maugeanus but was later synonymised with T. truncatus. Morphologically, these coastal dolphins share some characters with both aforementioned recognised Tursiops species, but they also possess unique characters not found in either. Recent mtDNA and microsatellite genetic evidence indicates deep evolutionary divergence between this dolphin and the two currently recognised Tursiops species. However, in accordance with the recommendations of the Workshop on Cetacean Systematics, and the Unified Species Concept the use of molecular evidence alone is inadequate for describing new species. Here we describe the macro-morphological, colouration and cranial characters of these animals, assess the available and new genetic data, and conclude that multiple lines of evidence clearly indicate a new species of dolphin. We demonstrate that the syntype material of T. maugeanus comprises two different species, one of which is the historical 'southern form of Tursiops' most similar to T. truncatus, and the other is representative of the new species and requires formal classification. These dolphins are here described as Tursiops australis sp. nov., with the common name of 'Burrunan Dolphin' following Australian aboriginal narrative. The recognition of T. australis sp. nov. is particularly significant given the endemism of this new species to a small geographic region of southern and south-eastern Australia, where only two small resident populations in close proximity to a major urban and agricultural centre are known, giving them a high conservation value and making them susceptible to numerous anthropogenic threats.
Journal Article
Role of winds and tides in timing of beach strandings, occurrence, and significance of swarms of the jellyfish Crambione mastigophora Mass 1903 (Scyphozoa: Rhizostomeae: Catostylidae) in north-western Australia
Very large swarms of the red jellyfish Crambione mastigophora in north-western Australia disrupt swimming on tourist beaches causing economic impacts. In October 2012, jellyfish stranding on Cable Beach (density 2.20 ± 0.43 ind. m⁻²) was estimated at 52.8 million individuals or 14,172 t wet weight along 15 km of beach. Reports of strandings after this period and up to 250 km south of this location indicate even larger swarm biomass. Strandings of jellyfish were significantly associated with a 2-day lag in conditions of small tidal ranges (<5 m). More than 90% of strandings occurred 2 days after winds were blowing onshore, but with the small number of days when satellite wind data were available during the study period, this result was not statistically significant. Dedicated instrument measurements of meteorological parameters, rather than the indirect measures used in this study (satellite winds and modelled currents) may improve the predictability of such events and help authorities to plan for and manage swimming activity on beaches. We also show a high incidence of predation by C. mastigophora on bivalve larvae which may have a significant impact on the reproductive output of pearl oyster broodstock in the region.
Journal Article
Two new species of Hydromedusae from Queensland, Australia (Hydrozoa, Leptothecata)
Two new species of small hydromedusae were found during routine monitoring in coastal waters of eastern Australia and are here described. The first, Melicertissaantrichardsoni Uribe-Palomino & Gershwin, sp. n. , from Moreton Bay, Queensland, is placed in its genus because of its possession of both cordyli and eight-fold symmetry. It differs from its congeners in two conspicuous features: firstly, having small, oval split gonads located adjacent to the base of the stomach, and secondly, in its extremely small size at maturity (2 mm bell diameter, compared to the next smallest species at 7 mm). Moreover, it possesses a unique combination of other characters. This species appears to be endemic to Moreton Bay. The second new species, Paraloveniayongalensis Gershwin & Uribe-Palomino, sp. n. , from the Great Barrier Reef, Queensland, is placed in its genus because of its two opposite normal tentacles and two opposite marginal clusters of cirri. It differs from its congeners primarily in a more rounded body than the others; the shape, length, and position of its short spindle-shaped, distal gonads; possession of subumbrellar nematocyst clusters; and possession of statocysts. These discoveries bring the total number of Melicertissa species to eight and the total number of Paralovenia species to three. The discovery of these two micromedusae underscores the need for further examination of the often-ignored minute and/or gelatinous fauna.
Journal Article
Abundant box jellyfish, Chironex sp. (Cnidaria: Cubozoa: Chirodropidae), discovered at depths of over 50 m on western Australian coastal reefs
Box jellyfish cause human fatalities and have a life cycle and habit associated with shallow waters (<5 m) in mangrove creeks, coastal beaches, embayments. In north-western Australia, tow video and epibenthic sled surveys discovered large numbers (64 in a 1500 m tow or 0.05 m
−2
) of
Chironex
sp. very near to the benthos (<50 cm) at depths of 39–56 m. This is the first record of a population of box jellyfish closely associated with the benthos at such depths.
Chironex
were not widespread, occurring only in 2 of 33 tow videos and 3 of 41 epibenthic sleds spread over 2000 km
2
. All
Chironex
filmed or captured were on low to medium relief reefs with rich filter feeder communities. None were on soft sediment habitat despite these habitats comprising 49% of all sites. The importance of the reef habitat to
Chironex
remains unclear. Being associated with filter feeder communities might represent a hazard, and other studies have shown
C. fleckeri
avoid habitats which represent a risk of entanglement of their tentacles. Most of our observations were made during the period of lowest tidal current flow in the morning. This may represent a period favourable for active hunting for prey close to the seabed.
Journal Article
Cotylorhiza erythraea Stiasny, 1920 (Scyphozoa: Rhizostomeae: Cepheidae), yet another erythraean jellyfish from the Mediterranean coast of Israel
An unfamiliar scyphozoan jellyfish species has been observed along the Mediterranean coast of Israel since 2003. Morphological characters such as the densely anastomosed radial canals and the stalked cupped appendages on the oral arms identified it as closely allied to
Cotylorhiza
. Comparison with the type of
C. erythraea
, collected over a century ago in the Suez Canal, shows close similarity. Molecular analyses based on the mitochondrial barcoding gene cytochrome oxidase sub unit I (COI) and 28S ribosomal DNA support its placement among the Cepheidae. This is the fifth-introduced scyphozoan species recorded along the Mediterranean coast of Israel. The presence of sexually mature specimens detected as far back as 2003, and the occurrence of the species in the past summer at sites nearly 90 kms apart, indicate the existence of widespread, established populations.
Journal Article
Systematics and Biogeography of the Jellyfish Aurelia labiata (Cnidaria: Scyphozoa)
The hypothesis that the common eastern North Pacific Aurelia is A. aurita is falsified with morphological analysis. The name Aurelia labiata is resurrected, and the species is redescribed, to refer to medusae differing from A. aurita by a suite of characters related to a broad and elongated manubrium. Specifically, the oral arms are short, separated by and arising from the base of the fleshy manubrium, and the planulae are brooded upon the manubrium itself, rather than on the oral arms. Aurelia aurita possesses on corresponding enlarged structure. Furthermore, the number of radial canals is typically much greater in A. labiata, and thus the canals often appear more anastomosed than in A. aurita. Finally, most A. labiata medusae possess a 16-scalloped bell margin, whereas the margin is 8-scalloped in most A. aurita. Separation of the two forms has previously been noted on the basis of allozyme and isozyme analyses and on the histology of the neuromuscular system. Partial 18S rDNA sequencing corroborates these findings. Three distinct morphotypes of A. labiata, corresponding to separate marine bioprovinces, have been identified among 17 populations from San Diego, California, to Prince William Sound, Alaska. The long-undisputed species A. limbata may be simply a color morph of A. labiata, or a species within a yet-unelaborated A. labiata species complex. The first known introduction of Aurelia cf. aurita into southern California waters is documented. Although traditional jellyfish taxonomy tends to recognize many species as cosmopolitan or nearly so, these results indicate that coastal species, such as A. labiata, may experience rapid divergence among isolated populations, and that the taxonomy of such species should therefore be scrutinized with special care.
Journal Article
A new pygmy species of box jellyfish (Cubozoa: Chirodropida) from sub-tropical Australia
Tropical box jellyfish include some of the world's most venomous animals, leading researchers and the media to wonder whether changes in climate may drive these species into sub-tropical waters. The discovery, therefore, of small box jellyfish in the waterways of the Gold Coast and Sunshine Coast of south-east Queensland raised concern. This pygmy species proved to be new to science, separated from other species in the genus Chiropsella by its very small size; its semi-circular phacellae; very shallow, coalesced gastric saccules; its peculiar, long pedalia where the ‘palm’ is greatly reduced and the non-opposing ‘fingers’ branch off together at the same level; and a knee-like bend of the pedalial canal. The residential canal/river habitat of this species of chirodropid raises the question of whether this area is also suitable for habitation by the larger, more virulent chirodropids such as the so-called ‘deadly box jellyfish’, Chironex fleckeri. This new species, Chiropsella saxoni sp. nov., brings the total number of chirodropid species described from Australian waters to five.
Journal Article
Comparison of Eight Types of Protective Clothing against Irukandji Jellyfish Stings
Marine stingers hospitalize approximately 100 people annually in tropical Australian waters, and are known to have caused at least 73 fatalities. Elsewhere in the tropical and temperate seas of the world, marine stingers pose a similar threat to human safety, and reported sting numbers are on the rise. Lycra body suits (“stinger suits”) have been used for stinger protection since the early 1980s, but have not been formally tested as a barrier against Irukandji (Carukia barnesi) tentacles. Other products are being used and developed; however, no safety standards currently exist for this widely used form of protective equipment. Eight products were tested with live C. barnesi: a Lycra stinger suit used by Surf Life Saving, a product developed by ROBIS Pty. Ltd. and marketed as “The Stinger Suit”, three different styles of nylon pantyhose, two sport products designed to “wick away” moisture and keep the wearer cooler, and a 0.5-mm neoprene wetsuit. Products were evaluated for seven common concerns relating to safety and practical wearability. Primary concerns, i.e., those relating to performance of the fabric in preventing stings, include: ease of penetration by jellyfish tentacles, adherence of tentacles or body to fabric, and potential for crushing through the fabric. Secondary concerns, i.e., those relating to overall usage as stinger-preventative clothing, include: durability or integrity of the barrier, whether the product is available as a one-piece garment, heat-retention properties, and product cost. In general, the tighter the fabric weave, the better tentacle exclusion, and the smoother the fabric, the more resistant to adherence. Lycra is vulnerable to crushing of tentacles through the fabric, but appears to be the best choice for routine-use stinger-protective clothing. Recommendations are made for safe use of protective clothing, as a basis for development of an Australian Standard in protective clothing for marine stinger safety.
Journal Article
A modern description of Crambionella stuhlmanni (Scyphozoa: Rhizostomeae) from St Lucia Estuary, South Africa
A new record of Crambionella stuhlmanni is reported from the east coast of South Africa. The material is described using quantitative morphological data, and mitochondrial (CO1) and nuclear (ITS-1) sequence data. The species can be diagnosed by a combination of morphological features including the presence of conical projections on velar lappets, the absence of orbicular appendages among mouthlets and the short length of the terminal club on the oral arm. Mitochondrial sequence data unambiguously delineate C. stuhlmanni as a separate species from C. orsini, and phylogenetic analyses support its placement within the monophyletic genus, Crambionella.
Journal Article