Genetic differentiation across eastern Pacific oceanographic barriers in the threatened seahorse <Emphasis Type="Italic">Hippocampus ingens</Emphasis>

Understanding the population structure and evolutionary history of the eastern Pacific seahorse Hippocampus ingens is critical for the effective management of this threatened species. Life history characteristics of H. ingens (site fidelity and brooding of young) may limit gene flow and lead to population differentiation. A recent study analyzing conserved fragments of the mitochondrial cyt b and control region found no population structure. We re-assess this conclusion with a phylogeographic analysis of relationships among 115 individuals of H. ingens over a broader geographic range (San Diego Bay in California, Gulf of California, Central America, Ecuador, and Peru) based on a more variable 428 base pair fragment of the control region. This expanded analysis affirms low overall nucleotide diversity relative to other seahorses (θ_π = 0.004), and shows evidence of a recent bottleneck and population expansion since the middle Pleistocene. AMOVA analysis shows moderate overall population structure (Φ_ST = 0.10, P val = 0.00), and pairwise Φ_ST estimates indicate structure between the Gulf of California and all Pacific coast localities. Knowledge of population structure in H. ingens may improve conservation efforts by identifying evolutionarily important management units, and could determine source regions in the continuing trade of seahorses for traditional Chinese medicine. The level of genetic divergence observed between the Gulf of California and all other localities sampled may distinguish the Gulf as a separate management unit. Additional phylogeographic research with more quickly evolving genetic markers and targeted sampling at the mouth of the Gulf of California is warranted to inform strategies for conservation of this threatened seahorse.     

The tip of the tail: molecular identification of seahorses for sale in apothecary shops and curio stores in California

Millions of seahorses a year are traded internationally, with many eventually sold at retail shops as curios, as aquarium pets, and especially for use in traditional medicine. The entire genus is now protected by CITES, but conservation measures have been limited in part by difficulties with species identification and incomplete understanding of trade patterns. In this study, we use molecular techniques to make species- and population-level identifications of 56 seahorses sampled from both traditional medicine and curio shops in San Francisco and central California. Seahorses from medicinal sources included unexpectedly large numbers of the eastern Pacific Hippocampus ingens, a species poorly protected by current CITES export recommendations. Curio shops were dominated by H. barbouri, a spiny species that has been reportedly confused in trading records as H. histrix. Specific populations of origin could be inferred for several species through comparison with publicly available phylogeographic data. Our results underscore the strengths and weaknesses of current recommended export regulations, and we suggest that molecular forensics can help in verifying trade documentation and developing more effective conservation measures.     

Molecular evidence for the presence of cryptic evolutionary lineages in the freshwater copepod genus <Emphasis Type="Italic">Hemidiaptomus</Emphasis> G.O. Sars, 1903 (Calanoida,Diaptomidae)

The pattern of morphological and mtDNA cytochrome b diversity of three calanoid copepod species belonging to the diaptomid genus Hemidiaptomus has been investigated with the aim of checking the reliability of the morphological characters currently used for species identification, and the possible presence of cryptic taxa. A sharply different molecular structuring has been observed in the studied species: while Hemidiaptomus amblyodon exhibits a remarkable constancy throughout the European range of its distribution area (maximum inter-populations cytochrome b divergence of 3%), observed distances between presumed conspecific lineages of Hemidiaptomus gurneyi (maximum divergence of 21.5%) and Hemidiaptomus ingens (maximum 19.1%) suggest that under these binomens are in fact included complexes of cryptic, or currently just unrecognized, independent evolutionary lineages. The application of the “4x rule” shows that the two lineages singled out within H. ingens are in fact independent evolutionary units, while the complex molecular structure observed in H. gurneyi s.l. could not be resolved based on the currently available data. Applying standard crustacean mtDNA evolutionary rates to the observed divergence values, the separation of the main lineages within both H. ingens and H. gurneyi might dates back to the Miocene; however, it has also to be considered that the rate of mtDNA evolution might be accelerated in copepods, as already observed in other arthropod taxa. Present results gives further evidences of the high potential for copepod speciation with no or little morphological changes, and stress the need of a revision of the most controversial Palaearctic diaptomid genera.     

Distribution and biomass of two squid species off southern New Zealand: Nototodarus sloanii and Moroteuthis ingens

The distribution and biomass of two species of squid, the ommastrephid arrow squid Nototodarus sloanii and the onychoteuthid squid Moroteuthis ingens, were analysed off southern New Zealand. These two species are the most important and abundant species in this region of the South Pacific Ocean. Data were obtained from extensive NIWA research cruises over 10 years. There was a sharp demarcation between the distribution of the two species, with N. sloanii occurring predominantly shallower than 600 m, with the greatest biomass less than 300 m. In contrast, M. ingens had the highest biomass between 650 and 700 m and occurred down to 1400 m. The biomass of N. sloanii reached more than 3500 kg · km⁻², with an average catch rate of over 186 kg · km⁻². In contrast, the biomass of M. ingens was more than an order of magnitude less, with all catch weights less than 200 kg · km⁻² and an average catch rate less than 17 kg · km⁻². The separation of these two species appeared to be related to depth, temperature and, possibly, salinity. N. sloanii occurred predominantly in warmer, shallower subtropical waters while M. ingens occurred in deeper, cooler subantarctic and antarctic intermediate water masses. The Subtropical Front formed a major barrier between the distribution of these two squid species. Accepted: 1 April 2000     

Hydrologic and mechanical control for an invasive wetland plant, <Emphasis Type="Italic">Juncus ingens</Emphasis>, and implications for rehabilitating and managing Murray River floodplain wetlands,Australia

Wetlands are prone to increased invasion by plant species following changes in hydrologic regime, leading to shifts in plant community composition and potentially ecosystem function and health. In this paper, the ecology and potential control of Juncus ingens, a native wetland plant in the Murray-Darling Basin of south-eastern Australia, is investigated. J. ingens has benefited from altered Murray River hydrologic conditions by expanding its range and invading seasonally-flooded grassland and riparian habitats along the Murray River. Here results of complementary glasshouse and field research of seedling and mature J. ingens growth and resilience as influenced by hydrologic regime (moist, saturated, partial inundation and when possible, complete inundation) and mechanical control (i.e., clipping) are presented. A moist hydrologic regime (soil held at field capacity) resulted in the most vigorous seedlings (13.9–73.0% more total biomass), while saturated conditions (flooding maintained level with the soil surface) resulted in the most vigorous mature J. ingens (14.1–98.4% more total biomass). Seedling mortality was greatest under complete and prolonged inundation (60% fatal with remaining 40% showing severe stress), conditions suspected to have limited prior invasion but which currently occur infrequently as a result of reduced flooding magnitude. Clipping was fatal for nearly all seedlings regardless of hydrologic regime but was only fatal for mature plants if coupled with prolonged inundation. Coupling ground-level clipping with strategic flooding may be the most effective means for controlling current populations of J. ingens and limiting further invasion, promoting re-colonisation by displaced species and rehabilitating the health of Barmah Forest and similar Murray River floodplain wetlands.     

Preliminary results on the ichthyocidal properties of Euphorbia ingens (Euphorbiaceae)

Euphorbia ingens belongs to the family Euphorbiaceae, which includes a variety of latex-producing plants, the majority of them having ichthyocidal properties (Coates-Palgrave 2000). Tests to determine the degree of virulence of E. ingens latex used Cyprinus carpio and Xenopus laevis as the main test organisms. Fish and frogs were exposed to various concentrations of latex to determine the concentration lethal only to the fish. The same concentrations were then used to determine the stability of the latex, by exposing fish in tanks with and without biological filtration. The breakdown period varied, with it breaking down quicker with biological filtration than without it. Once the stability of the latex within a system was determined, crabs, aquatic snails, frogs and fish were all simultaneously tested in a tank at the same concentration as before. Within 12 hours all the fish and half the frogs died, whereas the crabs and snails appeared not to suffer any detrimental effects. The poison degraded and became harmless to fish within 48 hours. Thus, the latex of Euphorbia ingens is a temporarily effective ichthyocide when applied in the correct concentrations.     

The ecology of yeast flora associated with cactiphilic Drosophila and their host plants in the Sonoran desert

Yeasts were isolated from the rotting stems of 7 species of cereoid cacti and 4 species ofDrosophila which utilize them as host plants. The yeast most common among 132 nonidentical isolates from the cacti and 187 nonidentical isolates from the flies, respectively, were:Pichia membranaefaciens (59 and 126),Candida ingens (22 and 8),Torulopsis sonorensis (16 and 20), andCryptococcus cereanus (11 and 14). Isolates capable of utilizingd-xylose were recovered primarily fromD. pachea andL. schotti. Adult flies were present on the substrates whenP. membranaefaciens was at high concentrations. As the pH of the substrates increased, the percent ofC. ingens cells increased relative to other yeast species. Larvae were detected mainly in alkaline substrates, and since adults did not yieldC. ingens to the extent the substrates did,C. ingens may be important in larval nutrition.Torulopsis sonorensis was recovered mainly fromD. mojavensis and its host plants,M. gummosus andL. thurberi. The concentration ofT. sonorensis in the substrates was negatively correlated with the temperature of the substrate.Cryptococcus cereanus was found in high concentrations in suitable tissues for adult flies but most adults did not yield this species to any extent. The yeast habitat diversities from the substrates had the following order:L. thurberi > C. gigantea > C. gigantea soils M. gummosus > L. schotti > others. Habitat diversity is discussed in relation to the variation of the physical conditions and chemical composition of the substrates. The yeast habitat diversities from the flies had the orderD. pachea > D. mojavensis D. nigrospiracula > undescribed Species M. The degree of habitat diversity is possibly a function of the surface feeding behavior of the flies.Research supported in part by grants from the National Science Foundation to W. B. Heed and H. W. Kircher (GB-43644X and GB-28953X1).     

Distribution and abundance of the squid Moroteuthis ingens (Cephalopoda: Onychoteuthidae) in the Falkland Islands region of the South Atlantic

The distribution and abundance of the onychoteuthid squid Moroteuthis ingens were assessed for the Patagonian Shelf in the Falkland Islands region. Catch records from the commercial fishery and a research cruise were recorded from 1988 to 1996. Sampling included benthic, pelagic and semi-pelagic trawls and jigging. Moroteuthis ingens was recorded from 1,414 stations out of a total of 9,060 stations with 79.9% of all positive stations being from benthic trawls. Catch size ranged up to approximately 3,000 kg. The length frequency analysis and maturity indices suggested a major recruitment onto the shelf in September with a movement off the shelf during winter. There appears to be a lack of mature females on the Patagonian Shelf, indicating that females migrate into deeper offshore water to spawn. Observations of predation on Moroteuthis ingens on the Patagonian Shelf, along with a literature review, revealed that at least 4 mammal, 17 bird and 13 fish species prey on this squid. Received: 30 October 1997 / Accepted: 11 April 1998     

Water exchange pertaining to host attachment sites and stream preference in crayfish-associated branchiobdellids, <Emphasis Type="Italic">Cambarincola fallax</Emphasis> and <Emphasis Type="Italic">Cambarincola ingens</Emphasis> (Annelida: Clitellata)

Water balance profiles were constructed for adults of two branchiobdellid species (Cambarincola fallax and Cambarincola ingens) to examine how they are differentially adapted for a freshwater habitat on different crayfish hosts. Both exhibited a high (75%) body water content and high net transpiration rate, reflecting that they are hyperosmotic to freshwater and display a consistent strategy that emphasizes water loss. In contrast to C. ingens, C. fallax was 6× smaller in body size, lost water 2× faster, and had heightened activation energy (E _a) for water permeability. Thus, C. fallax relies on high net transpiration rate with a focus on elimination, whereas the larger C. ingens are modified for water retention and rely on their low activation energy to suppress the amount of water that enters the body. Neither species showed evidence of a critical transition temperature (CTT), as indicated by an uninterrupted Boltzmann temperature function of passive water loss rates. No influence on favoring water balance was apparent in relation to the crayfish host with regard to preferred attachment sites (subrostral or branchial chamber) or preference for occupying different regions (pool vs. riffle) of the stream. Thus, water balance strategies between the two species are complementary, reflecting trade-offs that adjust for body size to promote survival in similar freshwater habitats. The ability of C. ingens and C. fallax to survive with a low water content, down to nearly 1/2 their body mass, however, enables them to cope with the excess water by permitting a high rate of water loss. Handling editor: K. Martens     

Assessing the conservation status of the strict endemic Desertas wolf spider,Hogna ingens (Araneae,Lycosidae)

The Desertas Islands (Madeira, Portugal) are the sole home of one of the largest and rarest wolf spider species, Hogna ingens (Blackwall 1857) (Araneae, Lycosidae). Despite its size, it inhabits a single valley in the North of the Deserta Grande Island, Vale da Castanheira, currently invaded by the herb Phalaris aquatica. This invasive species competes with the native flora and was subject to several eradication experiments, namely through fire and chemicals. The objectives of this work were to: (1) estimate the current distribution and abundance of H. ingens and respective trends; (2) evaluate the impact of the invasive plant and eradication methods on the spider population; (3) suggest future measures for the recovery of the species; and (4) evaluate its conservation status according to the IUCN criteria.The current distribution of H. ingens covers 23 ha, a recent reduction from its original 83 ha, corresponding to the entire Vale da Castanheira. A total of 4447 and 4086 adults and 71,832 and 24,635 juveniles were estimated to live in the valley during 2011 and 2012, respectively. We found a significant negative impact of P. aquatica cover on the presence and abundance of H. ingens and that chemical treatment specifically directed towards the invasive plant species may be the only way to effectively recover the spider's habitat. We suggest (1) regular monitoring; (2) extend chemical treatments; (3) ex-situ conservation with future reintroduction of adults. Based on the current area of occupancy (AOO) of H. ingens and its recent decline in both AOO and number of individuals, it was recently classified as Critically Endangered by IUCN and we suggest its urgent inclusion in the Habitats Directive species lists.     

Megalocypris ingens Delorme (Ostracoda) in Saskatchewan saline lakes: osmoregulation and abundance

Results of freezing point depression determinations show that the haemolymph of the ostracod, Megalocypris ingens Delorme, remains hyperosmotic to the medium as the concentration of the medium increases. Even though M. ingens is poikilosmotic, the median lethal concentration (LC50) for this species exceeds the LC50 for an insect species living in the same lakes that is capable of hyposmotic regulation. The LC50 for M. ingens occurred in sulphate-saline lake water with a specific conductance of 48 000 µS cm^-1 (at 25 °C). The absence of vegetation may be more important than salinity in limiting the distribution of M. ingens in Saskatchewan saline lakes.     

Bump-head sunfish Mola alexandrini photographed in the north-west Pacific Ocean mesopelagic zone

We report a bump-head sunfish Mola alexandrini (120–130 cm estimated total length) photographed from a manned submersible at a depth of 220 m off Kagoshima Prefecture, Japan, in May 2004. Mola alexandrini is often misidentified as the ocean sunfish Mola mola. This individual represented three records for this species: first record by a manned submersible, second record from the mesopelagic zone in the north-west Pacific Ocean and a new distributional record from Kagoshima Prefecture, Japan.     

First record of Terpios fugax Duchassaing and Michelotti, 1864 (Demospongiae: Suberitidae) in the Eastern Pacific Ocean

ABSTRACT

The brightly blue shallow water species Terpios fugax Duchassaing and Michelotti, 1864 was originally described from the Caribbean and has been extensively recorded in the Atlantic Ocean, but rarely found in the Indian and Pacific Oceans. In the Pacific Ocean it has been only reported from Sulawesi, Indonesia and from the Caroline and Marshall Islands. Here we report the first record of Terpios in the Eastern Pacific, based on the presence of T. fugax at Caldera, Región de Atacama, northern Chile. Although this species may have been inadvertently introduced to the area by human activity, it should also be considered that the geographically distant populations of this sponge (from the Caribbean to the Eastern Pacific) may represent different species.     

Algal Parasite Herpodiscus durvillaeae (Phaeophyceae: Sphacelariales) Inferred to have Traversed the Pacific Ocean with its Buoyant Host

The parasitic phaeophycean endophyte Herpodiscus durvillaeae (Lindauer) G. R. South has previously only been recorded from New Zealand, in association with a single host species, Durvillaea antarctica (Chamisso) Hariot (southern bull‐kelp). Here we use DNA sequence data from plastid and nuclear markers (chloroplast rbcL, ribosomal LSU, and a nuclear pseudogene copy of COI) to test for the presence of H. durvillaeae beyond the New Zealand region, and on host species other than D. antarctica. Analyses of samples from the Falkland Islands confirm the first record of H. durvillaeae from the Atlantic Ocean. We report that Falkland Islands H. durvillaeae are genetically indistinguishable from samples of this species from New Zealand's sub‐Antarctic Campbell Island, suggesting recent dispersal of the parasite across the Pacific Ocean, presumably by rafting with its buoyant macroalgal host. We also here record H. durvillaeae from New Zealand endemics Durvillaea poha Fraser et al. and D. willana Lindauer.     

Assessing the trophic ecology of three sympatric squid in the marine ecosystem off the Patagonian Shelf by combining stomach content and stable isotopic analyses

Squid species are important components of the Southern Atlantic Ocean ecosystems, as they prey on a wide range of crustaceans, fish and cephalopods. As a result of this trophic interaction and their high abundance, they are considered reliable indicators of energy transfer and biomass in the food web. We identified Illex argentinus, Doryteuthis gahi and Onykia ingens as the most important squid species interacting on the Patagonian shelf, and used isotope analysis and stomach content identification to assess the feeding ecology and interaction of these squids in the ecosystem. Our results describe trophic interactions by direct predation of O. ingens and I. argentinus on D. gahi, and a trophic overlap of the three squid, and indicate a higher trophic level and differences in the foraging areas for mature and maturing D. gahi inferred through δ¹⁵N and δ¹³C concentrations. These differences were related to the segregation and different habitat of large mature D. gahi and suggest a food enrichment of C and N based on feeding sources other than those used by small maturing D. gahi and I. argentinus and O. ingens.     

Top-down and bottom-up influences on populations of a stream detritivore

1. Knowledge of the influence of predatory fish in detritus‐based stream food webs is poor. We tested whether larval abundance of the New Zealand leaf‐shredding caddisfly, Zelandopsyche ingens (family Oeconesidae), was affected by the presence of predatory brown trout, Salmo trutta and the abundance of their primary detrital resource (Nothofagus leaves). 2. The density of Z. ingens and the biomass of leaves were determined in seven fishless streams and four trout streams in the Cass region, central South Island, on four occasions spanning 5 years. 3. Physicochemical conditions were similar in trout and fishless streams, but ancova indicated that Z. ingens numbers were positively related to leaf biomass and that caddisfly numbers were significantly greater in fishless streams than trout streams for any given biomass of leaf. The cases of trout stream larvae were also heavier per unit length than those in fishless streams. 4. Our results provide evidence for both top‐down and bottom‐up influences on a detritus‐based stream food web. Although stream detritivores may benefit from a habitat that provides both food and a degree of protection from predators, top‐down effects of predators on detritivore population abundance were still important. Thus, detrital resource availability may determine maximum attainable population size, whereas predation is likely to reduce the population to a level below that.     

The use of beaks as tools for biomass estimation in the deepwater squid Moroteuthis ingens (Cephalopoda: Onychoteuthidae) in New Zealand waters

Beak lengths (lower rostral length and upper rostral length) were taken for a sample of Moroteuthis ingens which were captured on the Chatham Rise, New Zealand. Beak lengths were plotted against both mantle length and wet weight to determine the relationship between these parameters for future use in biomass estimates in predator analysis. Although M. ingens is markedly sexually dimorphic, with females reaching 5 times the weight of males, there was no obvious sexual dimorphism in either lower or upper rostral length. This resulted in sex-specific relationships between both LRL and mantle length, LRL and weight; and URL and mantle length, and URL and weight. Males appeared to have a curvilinear relationship between beak length and mantle length and beak length and weight (even for log-transformed data). There was also considerable spread in the data in the plot between beak length and weight for females of similar weight. These characteristics of the data makes biomass estimates based on rostral length measurements for this species difficult. Other beak parameters may prove more useful for estimating biomass of M. ingens.     

Munnogonium affinissp. n.: A New Species of Isopod (Asellota: Paramunnidae) from the Coast of Korea,Sea of Japan

The new species Munnogonium affinisfrom the coast of Korea (the Sea of Japan) is described. This is the first record of the genus Munnogoniumfrom the western Pacific. The new species differs considerably from the four eastern Pacific American species of this genus and is most similar to M. maltiniifrom the Mediterranean Sea.     

Age, growth and maturation of the deepwater squid Moroteuthis ingens (Cephalopoda: Onychoteuthidae) in New Zealand waters

 Individuals of the deepwater squid Moro- teuthis ingens were obtained from New Zealand waters at depths between 500 and 1452 m. Depth distribution suggested that there was an ontogenetic migration to deeper water by females in association with maturity. Males did not show any clear pattern in their depth distribution. Statolith increment analysis was also undertaken to obtain putative age and life span information. Based on statolith age estimates, M. ingens appears to be predominantly an annual species with the oldest individuals aged at 358 and 393 days for males and females respectively. The form of growth over the size range sampled was linear with females having a growth rate almost twice that of males. Back-calculated hatching dates revealed a peak in hatching in the austral winter between June and August. Maturation in males was more closely related to size rather than age whereas in females the pattern in ovary growth in relation to both mantle length and age was similar. Received: 23 January 1996/Accepted: 29 May 1996     

Individual assignment tests proved genetic boundaries in a species complex of Pacific abalone (genus <Emphasis Type="Italic">Haliotis</Emphasis>)

We conducted this study to find genetic evidence to distinguish the members of Pacific abalone species complex (Haliotis discus hannai, H. discus discus, H. madaka, and H. gigantea) based on microsatellite DNA markers, illustrating the potential of microsatellites for species-assignment. First, we addressed the transferability of H. discus hannai microsatellites to the three other members of Pacific abalone and five additional species (H. diversicolor aquatilis, H. midae, H. corrugata, H. fulgens, and H. rubra). Second, using the microsatellites we applied two types of individual assignment testing (the distance-based assignment and Bayesian model-based clustering) to individuals from the Pacific abalone species. A total of 24 microsatellites were subjected to PCR trials for nine Haliotis species, and the cross-species amplification performance of these markers turned out to drop precipitously even for less divergent congeners. Within the Pacific abalone species complex, four of the 24 markers were not transferable to H. gigantea, suggesting a solid genetic boundary between H. gigantea and H. discus hannai, H. discus discus, and H. madaka. Among the three latter abalones, both assignment tests achieved approximately 90% or more success rate of assignment. The feasibility of the microsatellite markers to classify species sheds light on the genetic management of the Pacific abalone species complex. Electronic Supplementary Material  Supplementary material is available in the online version of this article at and is accessible for authorized users.