Mosaics in the mangroves: allopatric diversification of tree‐climbing mudwhelks (Gastropoda: Potamididae: Cerithidea) in the Indo‐West Pacific

The Indo‐Australian Archipelago (IAA) is the richest area of biodiversity in the marine realm, yet the processes that generate and maintain this diversity are poorly understood and have hardly been studied in the mangrove biotope. Cerithidea is a genus of marine and brackish‐water snails restricted to mangrove habitats in the Indo‐West Pacific, and its species are believed to have a short pelagic larval life. Using molecular and morphological techniques, we demonstrate the existence of 15 species, reconstruct their phylogeny and plot their geographical ranges. Sister species show a pattern of narrowly allopatric ranges across the IAA, with overlap only between clades that show evidence of ecological differentiation. These allopatric mosaic distributions suggest that speciation may have been driven by isolation during low sea‐level stands, during episodes preceding the Plio‐Pleistocene glaciations. The Makassar Strait forms a biogeographical barrier hindering eastward dispersal, corresponding to part of Wallace's Line in the terrestrial realm. Areas of maximum diversity of mangrove plants and their associated molluscs do not coincide closely. © 2013 The Natural History Museum. Biological Journal of the Linnean Society © 2013 The Linnean Society of London, 2013, 110 , 564–580.     

Molecular systematics of Vetigastropoda: Trochidae, Turbinidae and Trochoidea redefined

Trochoidea are a large superfamily of morphologically and ecologically diverse marine gastropods. We present here an appraisal of the composition and relationships among trochoidean families based on molecular data, with an especial focus on the family Trochidae. Bayesian analyses of sequences from three genes (18S rRNA, 28S rRNA and COI) including data from 162 vetigastropod species show that the gastropod family Trochidae (sensu  Hickman & McLean (1990 ), Natural History Museum Los Angeles County Science Series, 35, 1–169) is not monophyletic. Recognition of Chilodontidae, Solariellidae and Calliostomatidae at the family level is supported. Our new, more limited, definition of Trochidae includes the subfamilies Stomatellinae, Lirulariinae and Umboniinae and redefined Trochinae, Cantharidinae and Monodontinae. Halistylinae are provisionally retained in the Trochidae based on previous morphological studies. As redefined, Trochidae are a predominantly shallow‐water radiation in the tropics and subtropics. Some subfamilies and genera previously included in Trochidae have been moved to an enlarged family Turbinidae. The family Turbinidae has been redefined to include Turbininae, Skeneinae, Margaritinae, Tegulinae, Prisogasterinae and most surprisingly the commercially important genus Tectus Montfort, 1810. The new definition of Turbinidae means that the family includes both predominantly shallow and deep‐water clades as well as genera that are distributed across the globe from the poles to the tropics. A greater range of habitat is now seen in Turbinidae than in Trochidae. The redefined Trochidae and Turbinidae, together with Solariellidae, Calliostomatidae and Liotiidae, make up the superfamily Trochoidea. Phasianellidae and Colloniidae are recognized as belonging in a new superfamily, Phasianelloidea, and Angaria Röding, 1798 is recognized as belonging in a new superfamily, Angarioidea. Placement of Areneidae into a superfamily awaits further work.     

Tethyan relicts on continental coastlines of the northwestern Pacific Ocean and Australasia: molecular phylogeny and fossil record of batillariid gastropods (Caenogastropoda, Cerithioidea)

The Batillariidae are a family of cerithioidean gastropods consisting of 14 living species, classified in six to eight genera. They are abundant on sandy mudflats and sometimes on rocky shores, on continental margins in the warm-temperate to tropical regions of the northwestern Pacific Ocean, Australasia and the Americas. Using samples from all 14 nominal batillariid species, we present a molecular phylogenetic hypothesis constructed from two genes, mitochondrial 16S rRNA and nuclear 28S rRNA, with taxa from four marine cerithioidean families as outgroups (Cerithiidae, Modulidae, Planaxidae, Potamididae). The Batillariidae as traditionally conceived are not monophyletic, because the Neotropical 'batillariids' Lampanella and Rhinocoryne are sister to the Planaxidae. The monophyletic Batillariidae sensu stricto are restricted to the northwestern Pacific and Australasia; we suggest a revised generic classification consistent with our phylogenetic hypothesis and recognize the four genera Batillaria , Pyrazus , Velacumantus and Zeacumantus . We propose a definition of the family using shell characters, as a basis for a review of the extensive fossil record. Batillariids appeared in the Late Cretaceous or Palaeocene, and the extinct genera Pyrazopsis , Vicinocerithium and Granulolabium became diverse in the Tethyan realm before the group disappeared from Europe at the end of the Miocene. The Batillariidae s. s. reached Australia and New Zealand by the Late Oligocene, and the genera Pyrazus , Velacumantus and Zeacumantus still survive in this refugium of Tethyan fauna. Two lineages, Batillaria and the extinct Tateiwaia , migrated north to China and Japan in the Early Miocene, to establish the present disjunct distribution of this relictual group in southern Australasia and the Oriental region.     

Phylogenetic Position of Mammoth and Steller's Sea Cow Within Tethytheria Demonstrated by Mitochondrial DNA Sequences

Here we report DNA sequences from mitochondrial cytochrome b gene segments (1,005 base pairs per species) for the extinct woolly mammoth (Mammuthus primigenius) and Steller's sea cow (Hydrodamalis gigas) and the extant Asian elephant (Elephas maximus), the Western Indian manatee (Trichechus manatus), and the hyrax (Procavia capensis). These molecular data have allowed us to construct the phylogeny for the Tethytheria. Our molecular data resolve the trichotomy between the two species of living elephants and the mammoth and confirm that the mammoth was more closely related to the Asian elephant than to the African elephant. Our data also suggest that the sea cow–dugong divergence was likely as ancient as the dugong–manatee split, and it appears to have been much earlier (22 million years ago) than had been previously estimated (4–8 million years ago) by immunological comparison. Received: 8 August 1996 / Accepted: 30 September 1996     

Milankovitch 41 000-year cycles in lithofacies and molluscan content in the tropical Middle Miocene Nyalindung Formation, Jawa, Indonesia

Nine cyclothems based on changes in sedimentary facies and molluscan fossil associations are identified in the Middle Miocene (± 12 Ma) lower part of Nyalindung Formation, Cijarian River section, Sukabumi, West Jawa Province, Indonesia. Molluscan associations were studied in 75 blocks collected through the succession; 47 species of autochthonous molluscs, belonging to 38 genera, were separated from the blocks. Five molluscan associations were recognized through comparison of these species with their closest living analogues. A sedimentary cycle consists of two conformable lithologic units: in ascending order, a gravelly shellbed or gravelly/conglomeratic sandstone and a muddy fine to medium-grained sandstone. The exception is the basal cycle, which has an intercalation of limestone. The systematic change in the molluscan fossil associations within individual cycles indicates that lithological changes correspond to changes in water depth with an amplitude of about 30 m. The short time period represented by the section and the thin units (many not more than 2 m thick) indicates that the main cause of the cyclicity was orbitally induced climate change, representing Milankovitch-scale cycles of 41 000 years. This appears to be the first time Milankovitch sea-level cycles have been reported from the tropical regions of the Earth.     

Worldwide phylogeography of limpets of the order Patellogastropoda: molecular, morphological and palaeontological evidence

A molecular phylogeny, based on sequence data from three mitochondrial(12S rRNA, 16S rRNA and COI) genes, is presented for the Patellogastropoda,including representatives of almost all genera belonging tothe Acmaeidae, Lepetidae, Lottiidae, Nacellidae and Patellidae.For comparison, a smaller dataset of sequences from two nuclear(18S rRNA and 28S rRNA) genes is presented. The mitochondrialgene phylogeny shows considerable disagreement with earlierhypotheses derived from morphological data. The Patellidae,Nacellidae and Lepetidae are monophyletic, but the Acmaeidaeand Lottiidae are polyphyletic. The family Acmaeidae is dividedinto two clades corresponding to the subfamilies Acmaeinae andPectinodontinae, but these two do not form a clade. The Acmaeinaeare synonymized with the Lottiidae, and the Pectinodontinaeare elevated to familial rank. Our results suggest that thePatelloida profunda group (formerly assigned to the Lottiidae)is the most basal group within the Patellogastropoda. We assignthis group to a new genus, Eoacmaea, in the new family Eoacmaeidae.We used a Bayesian Markov-Chain Monte Carlo approach togetherwith the fossil record to estimate divergence times from thecombined DNA sequence data. The lineage of extant Patellogastropodais estimated to have originated as long ago as Late Jurassic.The phylogeny also suggests that the principal clades and antitropicaldistribution pattern of the Patellogastropoda formed duringthe Mesozoic to early Cenozoic, in association with the disruptionof Pangea and following the establishment and decline of thecircumglobal equatorial current. (Received 6 November 2006; accepted 19 December 2006)     

Light-Sensitive Vertical Migration of the Japanese Eel Anguilla japonica Revealed by Real-Time Tracking and Its Utilization for Geolocation

Short-time tracking (one to eight days) of the Japanese eel (Anguilla japonica) using ultrasonic transmitter was performed in the tropical-subtropical area adjacent to the spawning area and temperate area off the Japanese Archipelago. Of 16 eels (11 wild and five farmed) used, 10 wild eels displayed clear diel vertical migration (DVM) from the beginning, while the other five farmed eels tracked for 19 to 66 hours did not. During daytime, a significantly positive correlation between migration depth and light intensity recorded on the vessel was observed in the 10 wild eels, indicating that the eels were sensitive to sunlight even at the middle to lower mesopelagic zone (500 to 800 m). During nighttime, the eel migration depth was observed to be associated with the phase, rising and setting of the moon, indicating that the eels were sensitive to moonlight at the upper mesopelagic zone (<300 m). Two of 10 wild eels were in the yellow stage but shared similar DVM with the silver stage eels. Swimbladders of three silver stage eels were punctured before releasing, but very little effect on DVM was observed. The eels very punctually initiated descent upon nautical dawn and ascent upon sunset, enabling us to determine local times for sunrise and sunset, and hence this behavior may be used for geolocating eels. In fact, estimated positions of eels based on the depth trajectory data were comparable or even better than those obtained by light-based archival tag in other fish species.     

Modulation of the immune response to tumors by a novel synthetic compound, (4R)-3-benzoyl-N-[(1R)-1-phenylethyl]-4-thiazolidinecarboxamide (RS-0481)

Summary RS-0481, (4R)-3-benzoyl-N-[(1R)-phenylethyl]-4-thiazolidinecarboxamide, is a compound that can re-establish the function of certain lymphoid cell populations impaired by the presence of a growing tumor in an animal. The compound markedly augmented the tumorspecific cytotoxic T lymphocytes,Tdth (delayed-type hypersensitivity T cells), and the nonspecific lymphokine-activated-killer-cell-like cell responses. It also enhanced the tumor-inhibitory effect of macrophages in tumor-bearing mice, but not in normal mice, indicating that it enhances the antitumor immune responses. Lymphocytes from RS-0481-treated tumor-bearing mice released significantly higher amounts of macrophage-activating factor(s) (MAF) and interleukin-2(IL-2)-like factors in culture compared with lymphocytes from untreated animals. Also, sera from treated tumor bearers showed elevated colony-stimulating factor (CSF) activity. Although the compound did not influence the factor-producing activity in mice without tumor, it enhanced the responsiveness of their bone marrow cells, T cells, and macrophages to CSF, IL-2, and MAF. It seems therefore possible that the compound enhances the responsiveness of immunocompetent cells to cytokines, resulting in a marked augmentation of antitumor T cell responses in tumor-bearing mice. Consistently it inhibited the development of lymph node metastasis of transplanted X5563 plasmacytoma, and we showed that T cells play a decisive role in this inhibition. The compound also counteracted the development of suppressor T cell activity in the spleen of tumor-bearing mice.     

Speciation and dispersal along continental coastlines and island arcs in the Indo-West Pacific turbinid gastropod genus Lunella

Species trees were produced for the Indo-West Pacific (IWP) gastropod genus Lunella using MrBayes, BEAST, and *BEAST with sequence data from four genes. Three fossil records were used to calibrate a molecular clock. Eight cryptic species were recognized using statistical methods for species delimitation in combination with morphological differences. However, our results suggest caution in interpreting ESUs defined solely by the general mixed Yule Coalescent model in genera like Lunella, with lower dispersal abilities. Four almost entirely allopatric species groups were recovered that differ in ecology and distribution. Three groups occur predominantly along continental coastlines and one occurs on island arrays. Sympatric species occur only in the torquata and coronata groups along coastlines, whereas species in the cinerea group, distributed in two-dimensional island arrays, occur in complete allopatry. Dispersal along island arcs has been important in the maintenance of species distributions and gene flow among populations in the cinerea group. The emergence of new islands and their eventual subsidence over geological time has had important consequences for the isolation of populations and the eventual rise of new species in Lunella.