Molecular phylogeny of the Athetini–Lomechusini–Ecitocharini clade of aleocharine rove beetles (Insecta)

Elven, E., Bachmann, L. & Gusarov V. I. (2012) Molecular phylogeny of the Athetini–Lomechusini–Ecitocharini clade of aleocharine rove beetles (Insecta). —Zoologica Scripta, 41, 617–636. It has previously been shown that the Aleocharinae tribes Athetini and Lomechusini form a well‐supported clade, which also includes the small Neotropical tribe Ecitocharini. However, neither Athetini nor Lomechusini were recovered as monophyletic. In this study, we addressed the basal phylogenetic relationships among the three tribes using sequence data from (i) a mitochondrial fragment covering the COI, Leu2 and COII genes; (ii) a mitochondrial fragment covering part of the 16S gene, the Leu1 gene and part of the NADH 1 gene; and (iii) a part of the nuclear 18S gene, for 68 Athetini, 33 Lomechusini and 2 Ecitocharini species, plus representatives from 10 other tribes. The athetine subtribe Geostibina was recovered as sister group to the ‘true Lomechusini’, which included the type genus Lomechusa. The two clades formed a sister group to the main Athetini clade, which also included Ecitocharini and the ‘false Lomechusini’, a group of New World genera normally placed in Lomechusini. The following changes in classification are proposed: (i) Geostibina Seevers, 1978 is raised to tribal rank, and 13 Athetini genera are placed in Geostibini; (ii) Ecitodonia Seevers, 1965; Ecitopora Wasmann, 1887, and Tetradonia Wasmann, 1894 are moved from Lomechusini to Athetini; (iii) Ecitocharini Seevers, 1965 is placed in synonymy with Athetini; (iv) Discerota Mulsant & Rey, 1874 is tentatively included in Oxypodini; (v) Actocharina Bernhauer, 1907 is placed in synonymy with Hydrosmecta Thomson, 1858.     

Molecular phylogeny of the beetle tribe Oxypodini (Coleoptera: Staphylinidae: Aleocharinae)

This is the first study to comprehensively address the phylogeny of the tribe Oxypodini Thomson and its phylogenetic relationships to other tribes within the staphylinid subfamily Aleocharinae. Using the hitherto largest molecular dataset of Aleocharinae comprising of 4599 bp for representatives of 22 tribes, the Oxypodini are recovered as non‐monophyletic. Members of the tribe belong to three distantly related lineages within the Aleocharinae: (i) the Amarochara group as sister clade to the tribe Aleocharini, (ii) the subtribe Tachyusina within a clade that also includes the tribes Athetini and Hygronomini, (iii) all other Oxypodini in a clade that also includes the tribes Placusini, Hoplandriini and Liparocephalini. Based on the inferred phylogeny, five subtribes of the Oxypodini are recognized: Dinardina Mulsant & Rey, Meoticina Seevers, Microglottina Fenyes, Oxypodina Thomson and Phloeoporina Thomson. The following changes in the classification of the Aleocharinae are proposed: (i) Amarochara Thomson is removed from the Oxypodini and placed in the tribe Aleocharini; (ii) the subtribe Taxicerina Lohse of the Athetini is reinstated as tribe Taxicerini to include Discerota Mulsant & Rey, Halobrecta Thomson (both removed from the Oxypodini) and Taxicera Mulsant & Rey; (iii) the subtribe Tachyusina Thomson is excluded from the Oxypodini and provisionally treated as tribe Tachyusini; (iv) the oxypodine subtribe name Blepharhymenina Klimaszewski & Peck is placed in synonymy with the subtribe name Dinardina Mulsant & Rey.     

Two coastal Athetini (Coleoptera: Staphylinidae: Aleocharinae) species new to Korea

Two coastal species in the tribe Athetini, Osakatheta yasukoae Maruyama, Klimaszewski and Gusarov, and Psammostiba hilleri (Weise), are newly discovered from the Korean fauna. Diagnoses, habitus photographs and line drawings of median lobe are provided.     

Phylogeny and evolution of Mesozoic and extant lineages of Histeridae (Coleoptera), with discovery of a new subfamily Antigracilinae from the Lower Cretaceous

In order to place a newly discovered species Antigracilus costatus gen. sp. n. from the Lower Cretaceous Yixian Formation (China) and to assess previously unplaced fossil taxa, we investigated the relationships of extant and extinct lineages of Histeridae based on three data sets: (i) 69 morphological characters belonging to 48 taxa (representing all 11 subfamilies and 15 of 17 tribes of modern Histeridae); (ii) partitioned alignment of 6030 bp from downloaded nucleotide sequences (28S, CAD, COI, 18S) of 50 taxa (representing 10 subfamilies and 15 of 17 tribes of modern Histeridae); and (iii) a combined morphological and molecular dataset for 75 taxa. Phylogenetic analyses of the morphology and combined matrices recovered the new Lower Cretaceous taxon as a sister group to remaining Histeridae and it is placed in †Antigracilinae subfam. n. †Antigracilinae constitutes the earliest record of Histeridae from the Lower Cretaceous Yixian Formation (∼125 Myr), backdating the minimum age of the family by 25 Myr from the earliest Cenomanian (~99 Myr) to the Barremian of the Cretaceous Period. Our molecular phylogeny supports Histeridae to be divided into seven different clades, with currently recognised subfamilies Abraeinae (sensu lato), Saprininae, Chlamydopsinae, and Histerinae (sensu lato) recovered as monophyletic, while Dendrophilinae, Onthophilinae, and Tribalinae are polyphyletic taxa. The Burmese amber species †Pantostictus burmanicus Poinar & Brown is placed as a sister group to the tribe Plegaderini (Abraeinae) and was assigned as a new tribe Pantostictini trib. n. Both molecular and combined phylogenies recovered the subfamilies Trypanaeinae and Trypeticinae deeply within the subfamily Abraeinae (sensu lato), and they are downgraded into Trypanaeini stat. n. and Trypeticini stat. n.     

Morphological and Molecular Characterization of a New Species of Stephanopogon,Stephanopogon pattersoni n. sp.

Stephanopogon is a taxon of multiciliated protists that is now known to belong to Heterolobosea. Small subunit ribosomal DNA (SSU rDNA) phylogenies indicate that Stephanopogon is closely related to or descended from Percolomonas, a small tetraflagellate with a different feeding structure, thus these morphologically dissimilar taxa are of ongoing evolutionary interest. A new strain of Stephanopogon, KM041, was cultured, then characterized by light microscopy, electron microscopy, and SSU rDNA sequencing. KM041 is 18–35 μm (mean 26.8 μm) long, with six main ventral ciliary rows, one ventro‐lateral ciliary row, and three anterior barbs. It closely resembles Stephanopogon minuta Lei et al. 1999 in morphology, and is very closely related to an extinct culture “S. aff. minuta”, yet is markedly dissimilar in SSU rDNA sequence from a different isolate identified as S. minuta. This confirms that there are at least two distinct lineages of S. minuta‐like cells, and we describe KM041 as a new species, Stephanopogon pattersoni n. sp. The ultrastructure of KM041 resembles that of previously studied Stephanopogon species, though it has a novel paraxonemal structure in a few cilia. We note that a sub‐basal‐body pad and bulbous axosome are unlikely to be apomorphies for the Stephanopogon–Percolomonas clade.     

Phylogeny of Mesoamerican freshwater mussels and a revised tribe‐level classification of the Ambleminae

Evolutionary and ecological hypotheses of the freshwater mussel subfamily Ambleminae are intensely geographically biased—a consequence of the complete exclusion of Mesoamerican taxa in phylogenetic reconstructions of the clade. We set out to integrate a portion of the Mesoamerican freshwater mussel assemblage into existing hypotheses of amblemine classification and evolution by generating a molecular phylogeny that includes four previously unsampled Mesoamerican genera and nine species endemic to that region. Given the traditionally hypothesized affinity to Nearctic mussels and the understanding that classification should reflect common ancestry, we predicted that (a) Mesoamerican genera would be recovered as members of the recognized tribes of the Ambleminae, and (b) genera would be supported as monophyletic. The mutilocus phylogeny (COI + 28S + 16S) reported herein does not fully support either of those hypotheses. Neither Cyrtonaias nor Psorula were supported as monophyletic and we predict several other Mesoamerica genera are also non‐monophyletic. The reconstructed phylogeny recovered four independent lineages of Mesoamerican freshwater mussels and these clades are distributed across the phylogeny of the Ambleminae, including the tribe Quadrulini (Megalonaias), Lampsilini (two lineages: Cyrtonaias explicata/Sphenonaias microdon, and Pachynaias), and a previously unrecognized, exclusively Mesoamerican and Rio Grande clade consisting of the genera Psoronaias, Psorula and Popenaias. The latter clade possesses several morphological characteristics that distinguish it from its sister taxon, tribe Lampsilini, and we recognize this newly identified Mesoamerican clade as a fifth tribe of the Ambleminae attributable to the Popenaiadini Heard & Guckert, 1970. This revised classification more completely recognizes the suprageneric diversity of the Ambleminae.     

Three littoral Athetini (Coleoptera: Staphylinidae: Aleocharinae) species new to Korea

Three littoral Athetini species –Adota magnipennis (Bernhauer), Atheta ririkoae Sawada and Atheta tokiokai (Sawada) – are reported for the first time in Korea. Diagnoses, illustrations of the habitus and line drawings of diagnostic characters are provided.     

Spatial and temporal variation in the diet of the sandy beach gastropod Olivella minuta

Marine gastropods exert a strong influence on the structure of marine ecosystems through their foraging activities, yet little is known about how environmental differences in space and time may affect their feeding behavior. To enhance the knowledge about the trophic ecology of coastal benthic species, we investigated temporal and spatial variations in the diet of the sandy beach gastropod Olivella minuta. We collected individuals of O. minuta seasonally, over 1 year, at two sandy beaches with different morphodynamic characteristics (Araçá Bay, an ultra‐dissipative tidal flat, and Barequeçaba Beach, a dissipative beach) and analyzed the stomach contents of specimens of O. minuta. We identified approximately 15,000 food items, which we grouped into 14 categories. Thirteen food categories were found at each area, but significant differences in diet were observed between sites and sampling periods. Individuals from Araçá consumed an overall larger quantity and diversity of food items, which consisted mainly of foraminiferans, polychaetes, and crustaceans. At Barequeçaba, diatoms were the most important item, followed by crustaceans and polychaetes. Temporal variation depended on sites: the number of food items in the stomachs of individuals of O. minuta and dietary composition was roughly constant over time at Araçá, whereas larger variations were observed at Barequeçaba. Although O. minuta has been previously characterized as a carnivore/scavenger, our results show that the diet of this species varies in space and time and comprises a large variety of food resources. The species thus plays a role in the cycling of both vegetal and animal organic matter. This generalist behavior may allow individuals to shift their diet according to habitat alterations and food availability, thereby enhancing the persistence and resilience of O. minuta in different environments or future climate change scenarios.     

Phylogeny of the parasitic wasp subfamily Euphorinae (Braconidae) and evolution of its host preferences

The braconid subfamily Euphorinae is a large, cosmopolitan group of endoparasitoid wasps. The majority of species attack adult hosts, a strategy that is rare among parasitic wasps, but there are also many species that attack nymphs and larval stages. Euphorine hosts may belong to a variety of insect orders (Coleoptera, Hemiptera, Hymenoptera, Neuroptera, Psocoptera, Orthoptera and Lepidoptera) although most euphorine tribes are confined to Coleoptera. Here we investigate the phylogenetic relationships of the Euphorinae based on molecular data (3 kb of nucleotide data from four markers: 18S, 28S, CAD and COI) and propose a higher‐level classification based upon the resulting phylogeny. We also infer the evolution of host associations and discuss the diversification of the Euphorinae. Results from both Bayesian inference and maximum‐likelihood analysis show that the subfamily, as previously circumscribed, is paraphyletic. We propose that the subfamily be expanded to include the tribes Meteorini and Planitorini (Mannokeraia + Planitorus), so that it corresponds to a clade that is strongly supported as monophyletic in our analyses. Based on our results, a revised higher classification of the Euphorinae is proposed, in which 52 extant genera and 14 tribes are recognized. We reinstate the genus Microctonus belonging to the tribe Perilitini, and synonymize Ussuraridelus with Holdawayella, Sinuatophorus with Eucosmophorus. Furthermore, we propose the following tribal rearrangements: Spathicopis and Stenothremma are transferred to Perilitini; Tuberidelus, Eucosmophorus and Plynops to Cosmophorini; Ecclitura to Dinocampini; Chrysopophthorus, Holdawayella and Wesmaelia to Helorimorphini; Proclithroporus and Heia to Townesilitini. The monotypic tribe Cryptoxilonini is synonymized with Cosmophorini. The genera Pygostolus and Litostolus are placed in a separate tribe, Pygostolini, previously recognized as a subtribe among the Centistini. Parsimony‐based ancestral state reconstructions suggest that the ancestor of Euphorinae was a parasitoid of lepidopteran larvae, and that a host shift to larval Coleoptera occurred only in one clade of the Meteorini, some members of which secondarily shifted back to larval lepidopteran hosts. In the remainder of the subfamily, there was an initial shift from larval to adult coleopterans, followed by subsequent shifts to adults or larvae of Hemiptera, Hymenoptera, Neuroptera, Orthoptera and Psocoptera.     

Free‐living calamyzin chrysopetalids (Annelida) from methane seeps,anoxic basins,and whale falls

Members of Calamyzinae, a clade of free‐living and ectoparasitic chrysopetalids, are mainly associated with deep‐sea chemosynthetic environments. The three currently known free‐living calamyzin species are placed in Vigtorniella. A new free‐living calamyzin species similar to these is described here. Phylogenetic analyses of Calamyzinae using mitochondrial (cytochrome c oxidase subunit I and 16S rDNA) and nuclear (Histone H3 and 18S rDNA) loci showed that Vigtorniella and the new species form a grade with respect to an ectoparasitic clade, requiring two new genera to be erected. All free‐living calamyzins show a similar anterior end and chaetal morphology. Micospina auribohnorum gen. et sp. nov. is described for the small‐bodied new species from deep‐sea whale falls off California and methane seeps off Costa Rica. The maximum‐likelihood and Bayesian analyses show Micospina gen. nov. as sister to the ectoparasitic clade. Boudemos gen. nov. is named for the clade of two larger‐bodied species: Boudemos flokati gen. et comb. nov. and Boudemos ardabilia gen. et comb. nov., which is sister group to all other Calamyzinae. Vigtorniella is retained for the type species, Vigtorniella zaikai (Kiseleva, 1992), with the adults found amongst bacterial mats at the boundary of the hydrogen sulphide zone in the Black Sea. Micospina gen. nov., Boudemos gen. nov., and Vigtorniella form a grade of free‐living taxa that is associated with feeding on organic‐enriched sediments, and the latter two taxa display ontogenetic jaw change. Jaws are absent in Micospina auribohnorum gen. et sp. nov. and most of the calamyzin clade of parasitic forms.     

Phylogenetics,delimitation and historical biogeography of the pantropical tree genus Thespesia (Malvaceae,Gossypieae)

Thespesia consists of 16 species of trees and shrubs from Southeast Asia–Oceania, Africa and America, the most well known being T. populnea, a small tree of tropical coastal areas around the world. Phylogenetic relationships in the genus and among its allies in tribe Gossypieae were inferred using three plastid and two nuclear regions to ascertain its generic delimitation and explore its biogeographical history. Maximum‐likelihood and Bayesian analyses confirmed that Thespesia is not monophyletic and, based on these results, Azanza is reinstated to accommodate the two species previously placed in Thespesia section Lampas. Dating analyses and ancestral range estimation indicated that Thespesia s.s. most likely originated in Southeast Asia–Oceania c. 30 Mya, but extant species did not begin to differentiate until the late Miocene. Two dispersal events, one into Africa c. 11 Mya and another into America (Antilles) c. 9 Mya, gave rise to the African and the Greater Antillean endemics, respectively. The two most widespread hydrochorous species, T. populnea and T. populneoides, originated in Southeast Asia–Oceania from where they spread to other parts of the world. Our analysis also indicated a much earlier origin than previously reported for the eumalvoid clade and its tribes Gossypieae, Malveae and Hibisceae suggesting that vicariance might have had an important role early in the history of these groups.     

Species trees,temporal divergence and historical biogeography of coastal rove beetles (Coleoptera: Staphylinidae) reveal their early Miocene origin and show that most divergence events occurred in the early Pliocene along the Pacific coasts

We investigated the species trees, temporal divergence and historical biogeography of Emplenota Casey and Triochara Bernhauer (ET clade hereafter), subgenera of the Aleochara coastal staphylinid beetles, to determine their place of origin. We explored a multilocus dataset to infer gene trees and species trees based on traditional concatenated and multispecies coalescent‐based approaches using both model‐ (maximum likelihood and Bayesian) and parsimony‐based methods. The multilocus dataset comprised DNA sequences from five nuclear genes (ArgK, CAD, EF1‐α, wg and 28S) and three mitochondrial genes (COI, COII and 16S). *BEAST analysis according to a coalescent‐based approach resolved the following phylogenetic relationships: ((A. trisulcata (A. nubis + A. zerchei)) (A. obscurella ((A. pacifica (A. curtidens + A. litoralis)) (A. hayamai (A. yamato (A. fucicola (A. segregata + A. puetzi))))))). Using a relaxed molecular clock, we reconstructed a time‐calibrated phylogeny for this group. Furthermore, to account for the historical biogeography of the ET clade at the ages of major divergences, we investigated the ancestral area based on a time‐calibrated phylogeny. Biogeographical analyses suggested that the ancestor of the ET clade was widely distributed along the eastern and western Palearctic and the western Nearctic coasts in the early Miocene. According to reconstruction of the ancestral area, one dispersal and three vicariance events were required, and the analyses indicated that vicariance events were important in shaping its current distribution patterns. Most of the divergence events occurred in the late Miocene and early Pliocene along the Pacific coasts, and the East Asian seacoasts harboured the most species‐rich fauna, including eight of the 13 species in the ET clade.     

Phylogeny and historical biogeography of leafhopper subfamily Iassinae (Hemiptera: Cicadellidae) with a revised tribal classification based on morphological and molecular data

Phylogenetic relationships among major lineages of the leafhopper subfamily Iassinae were explored by analysing a dataset of 91 discrete morphological characters and DNA sequence data from nuclear 28S rDNA and histone H3 genes and mitochondrial 12S rDNA. Bayesian, maximum‐likelihood and maximum parsimony analyses yielded similar tree topologies that were well resolved with strong branch support except at the base of the tree, resulting in equivocal support for inclusion of Bythoniini as a tribe of Iassinae but strong support for the monophyly of Iassinae (excluding Bythoniini) and most previously recognized iassine tribes. Divergence times for recovered nodes were estimated using a Bayesian relaxed clock method with two fossil calibration points. The results suggest that the deepest divergences coincided with Gondwanan vicariant events but that more recent divergences resulted from long‐range dispersal and colonization. Biogeographical analyses suggest that the group most likely has a Neotropical origin. The following changes to the taxonomic classification are proposed: establishment of three new tribes, Batracomorphini trib.n. (based on type genus Batracomorphus Lewis), Hoplojassini trib.n. (based on type genus Hoplojassus Dietrich and including one other South American genus), Lipokrisnini trib.n. (based on type genus Lipokrisna Freytag and including two other endemic Caribbean genera); Krisnini is redefined to include only the Old World genera Krisna and Gessius; Iassini is redefined to include only the type genus and four endemic Afrotropical genera; Bascarrhinus Fowler and Platyhynna Berg, recently treated as genera incertae sedis, are placed in Hyalojassini; Thalattoscopus Kirkaldy is added to the previously monobasic tribe Trocnadini. Iassinae now includes 12 tribes, all of which appear to be monophyletic. Revised morphological diagnoses of the subfamily and each of the included tribes are provided and a key to tribes is also given. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:41295B68‐2DAB‐4C4F‐B260‐F7C054922173 .     

The status of Eurostus dussumierii and Hypsirhina chinensis (Reptilia,Squamata, Serpentes): with comments on the origin of salt tolerance in homalopsid snakes

The Kerala mud snake, Enhydris dussumierii Duméril, Bibron & Duméril, has long been known only from syntypes collected in the nineteenth century, but more recent specimens have provided the opportunity for molecular work. Using Bayesian phylogenetic analysis of 2200 base pairs of cytb, 16S, and c-mos, we recovered the Kerala mud snake as the sister species to the Chinese mud snake, Enhydris chinensis (Chinese–Vietnamese endemic). The DNA results establish the position of dussumierii and chinensis as separate from the Enhydris clade, and together they form the sister group to most of the other fanged homalopsids ((Bitia+Cantoria) + (Erpeton+Gerarda+Fordonia) + (Myron+Pseudoferania) + (Enhydris punctata) + (Homalopsis+Enhydris bocourti) + (Cerberus)). Here we resurrect Ferania Gray for Enhydris sieboldii Gray, establish a new genus for the E. chinensis clade (bennettii+chinensis), and apply the generic replacement name Dieurostus Berg to E. dussumierii Duméril, Bibron & Duméril. A biogeographic scenario is proposed based on the ecology, distribution and salt tolerance of the species composing a hypothesized (not supported with molecular evidence) Asian coastal lineage that is distributed from Pakistan's Indus River delta to temperate coastal China.     

Phylogeny of Adramini (Diptera,Tephritidae) based on integrative evidence

Species of the tribe Adramini (Tephritidae: Trypetinae) are usually slender, and some specific species have eyes borne at the ends of their long stalks. This tribe is mainly distributed in the tropics and subtropics of the Afrotropical, Oriental and Australasian Regions; relatively few species occur in the Palearctic and Nearctic Regions. The phylogeny of the tribe Adramini is presented here based on analysis of morphological and molecular information (DNA sequences of nuclear 28S rDNA, mitochondrial COI and COII, and 16S rDNA genes) for its representative species in most genera. Three monophyletic groups (Adrama‐com‐group, Pelmatops‐com‐group and Dimeringophrys‐com‐group) were discovered in the combined morphological and molecular tree. The results showed moderate support for the monophyly of Adramini and strong support for most of its genera. However, Euphranta appears to be polyphyletic. Sapadrama, Celidodacus and Euphranta are basal taxon, and Coelopacidia, Soita and Trypanophion are closely related to the stalk‐eyed fruit flies (Pelmatops + Pseudopelmatops). A hypothesis regarding the morphology–function relationships for two main groups of Adramini (Adrama‐group and Pelmatops‐group) with different evolving probabilities is inferred. Sapadrama is proposed be removed from Adramini; a new genus, Ichneumonomacula Chen gen. n. and a new species Ichneumonmacula wangyongi Chen sp. n., are recognized and described, and a key to recognize the genera of Adramini around the world is provided.     

Corema album: unbiased dioecy in a competitive environment

• Corema album is a dioecious coastal shrub. Dioecious plants growing in these resource‐limited habitats may present spatial segregation of the sexes (SSS) or demographic biases because of the different reproductive effort between sexes. In these environments facilitation is a more common interaction between plants than competition. To assess factors determining the distribution of C. album male and female plants, we investigated the influence of habitat type (sand dunes and coastal woodlands), assessed the occurrence of SSS or demographic biases and also a possible role of these shrubs as nurse plants.
• We selected three C. album populations with the two habitat types. All C. album individuals were sexed, mapped and measured in three plots (20 m × 20 m) per population/habitat type. Presence and abundance of all plant species were recorded under five female and five male C. album plants as well as in equivalent open ground area in each of 15 plots.
• According to Ripley's K function result, C. album did not display SSS. Generalised linear mixed models (GLMM) show that differences in plant size were not related to plant sex. Plant inventory correspondence analysis showed that species composition and abundance were influenced by habitat type, population and the presence of a C. album individual, but not by its sex. GLMM indicated a detrimental effect of C. album on the co‐occurring plants.
• Our results show that sexual dimorphism has allowed C. album to adapt to the environment avoiding SSS or significant demographic bias, suggesting a positive outlook for its conservation.

     

A molecular and morphological reassessment of the phylogeny of the subfamily Ophioninae (Hymenoptera: Ichneumonidae)

The phylogeny of the subfamily Ophioninae (Hymenoptera: Ichneumonidae) is investigated using molecular markers and morphological characters. We analysed the mitochondrial DNA CO1 and the nuclear 28S D2–D3 gene fragments for 74 species of Ophioninae from 25 out of the 32 recognized genera, which collectively represent 98% of described species diversity of the subfamily. Molecular markers were analysed separately and combined, with or without the adjunction of a matrix of 62 morphological characters using Bayesian inference. Our results reveal three distinct lineages, each including one of most speciose genera: Ophion, Enicospilus and Thyreodon. The comparison of the molecular data, and combined molecular plus morphological data led to the definition of the three tribes: Ophionini stat. rev. (Ophion + Alophophion + Rhopalophion + Xylophion + Afrophion); Enicospilini stat. rev. (Enicospilus + Laticoleus + Dicamptus + Hellwigiella); and Thyreodonini tribe nov. (Thyreodon + Dictyonotus + Rhynchophion). The possible association of other genera to one or another of these lineages is discussed. Ophion is a polyphyletic assemblage and requires a further revision to define the delimitation with close genera. The enigmatic Old World genus Skiapus is strongly supported as belonging to the Ophioninae, although its placement within the subfamily is ambiguous as a result of its derived genotype and phenotype. Finally, we propose a biogeographical scenario supported by this phylogeny and based on the limited available fossil data.     

Phylogenetic study of benthic, spine-bearing prorocentroids, including Prorocentrum fukuyoi sp. nov.

Species of prorocentroid dinoflagellates are common in marine benthic sediment and epibenthic habitats, as well as in planktonic habitats. Marine planktonic prorocentroids typically possess a small spine in the apical region. In this study, we describe a new, potentially widely distributed benthic species of Prorocentrum, P. fukuyoi sp. nov., from tidal sand habitats in several sites in Australia and from central Japan. This species was found to possess an apical spine or flange and was sister species to P. emarginatum. We analyzed the phylogeny of the group including this new species, based on large subunit (LSU) rDNA sequences. The genus contained a high level of divergence in LSU rDNA, in some cases among sister taxa. P. fukuyoi and P. emarginatum were found to be most closely related to a clade of generally planktonic taxa. Several morphological features may constitute more informative synapomorphies than habitat in distinguishing clades of prorocentroid species.