Reconstructing the species phylogeny of Pseudopanax (Araliaceae), a genus of hybridising trees

Pseudopanax (Araliaceae) comprises 12 tree species of diverse morphology and ecology, and is endemic to New Zealand. It is notable for the hybridisation that occurs between P. crassifolius and P. lessonii, which have very different leaves and habits. To provide context for the study of this hybridisation and other investigations, we examined the phylogeny of Pseudopanax using chloroplast DNA sequences (c.5900 base-pairs) and AFLP DNA-fingerprinting. Both approaches resolve two principal groups within Pseudopanax – the Arboreus group and the Crassifolius + Lessonii union – but how they are related to other genera remains unclear. There is, nevertheless, little compelling evidence against the monophyly of Pseudopanax, making unnecessary the recent re-segregation of the Arboreus group as Neopanax. The chloroplast data provided minimal additional resolution, although the position of P. linearis was discordant compared to other data. Analyses of the AFLP data strongly recovered each species, aside from the morphologically heterogeneous P. colensoi, and the two mainland species (P. arboreus and P. crassifolius) that each contained a nested island-endemic (P. kermadecensis and P. chathamicus, respectively). However, relationships amongst species within the two principal groups were poorly resolved. An example was the uncertainty of whether P. crassifolius grouped with P. lessonii and its allies, or the morphologically similar species it had been previously placed with. This in turn raises the issue of how hybridisation might affect phylogenies and the ability to reconstruct them, even when using multiple, independent markers.     

Morphological and molecular characteristics of selected species of Minidiscus (Bacillariophyta,Thalassiosiraceae)

We report on taxonomically distinguishing morphological features of six diatom taxa from the marine, nanoplanktonic genus, Minidiscus, found in Eastern Canada and neighbouring waters. Four of the six were also investigated using genetic approaches. We found that the culture deposited in the Provasoli-Guillard National Center for Culture of Marine Phytoplankton (CCMP) as CCMP 496 was morphologically closest to the published type image of M. trioculatus, whereas other isolates were morphologically and/or genetically divergent. Consequently, we propose three new taxa. One monoclonal line isolated from the Bay of Fundy is proposed as a new variety, M. trioculatus var. monoculatus. The well-studied nanoplanktonic diatom strain, CCMP 495, currently considered to be ‘M. trioculatus’ was morphologically and genetically divergent from CCMP 496 and we propose specific status for it, M. variabilis. We isolated a new strain from the Gulf of St Lawrence that was nearly genetically identical in 18S and ITS regions to CCMP 495, but showed distinct morphological differences and we propose a new form for this strain. Culture-based data were supplemented by those from natural seawater whenever possible. Two species (M. comicus, M. chilensis) known from our region, but unavailable in culture, are presented for comparison.     

Nematode lungworms of two species of anuran amphibians: evidence for co-adaptation

Genetic studies have indicated that some parasite species formerly thought to be generalists are complexes of morphologically similar species, each appearing to specialize on different host species. Studies on such species are needed to obtain ecological and parasitological data to address whether there are fitness costs in parasitizing atypical host species. We examined whether lungworms from two anuran host species, Lithobates sylvaticus and Lithobates pipiens, differed in measures of infection success in L. pipiens recipient hosts. We also determined if the worms from the two host species were sources of genetically resolvable species of morphologically similar nematodes. Sequences of internal transcribed spacer and lsrDNA regions of adult lungworms from each host species indicated that worms from L. sylvaticus matched Rhabdias bakeri, whereas worms from L. pipiens matched Rhabdias ranae. Our work suggested that these morphologically similar species are distant non-sibling taxa. We infected male and female metamorphs experimentally with lungworm larvae of the two species. We observed higher penetration, higher prevalence and higher mean abundance of adult worms in lungs of male and female metamorphs exposed to R. ranae larvae than in lungs of metamorphs exposed to R. bakeri larvae. Furthermore, metamorphs exposed to R. ranae larvae carried larger adult female worms in their lungs. Some variation in infection measures depended on host sex, but only for one parasite species considered. Overall, the differential establishment and reproductive potential of R. ranae and R. bakeri in L. pipiens suggests co-adaptation.     

Craniodental Characters in the Taxonomy of Propithecus

The indriid genus Propithecus comprises the sifakas, medium-sized lemurs endemic to the forests of Madagascar. Traditionally, scientists divided the genus into only 2 or 3 species —Propithecus diadema, P. verreauxi, and, since 1988, P. tattersalli— with 4 or 5 subspecies in each of the first 2 taxa, but recent authors have suggested that many more distinct species should be recognized. We draw from quantitative and qualitative studies of craniodental traits to evaluate further the phenetic distinctiveness and taxonomic status of each named form of Propithecus. We recognize 9–10 species in the genus. The 4 or 5 species of the Propithecus diadema group —P. diadema, P. candidus, P. perrieri, P. edwardsi, and perhaps P. holomelas, if distinct— share several derived features, including large average body size and a mandible specialized for rotational chewing, and clearly comprise a closely related complex. The 5 species of the Propithecus verreauxi group —P. verreauxi, P. coquereli, P. deckenii, P. coronatus, P. tattersalli— are each highly distinctive morphologically and likely do not comprise a monophyletic group. In particular, we point out the highly distinctive cranial features of Propithecus coronatus, which researchers have traditionally largely overlooked.     

A BIOSYSTEMATIC STUDY OF THE POLYGONUM HYDROPIPEROIDES (POLYGONACEAE) COMPLEX

The Polygonum hydropiperoides complex includes P. hydropiperoides Michx., P. opelousanum Riddell ex Small, P. setaceum Baldwin ex Ell., and P. hisutum Walter. Studies of morphology, cytology, and crossing compatibility were conducted with specimens from North Carolina, South Carolina, Georgia, and Florida. A multivariate cluster analysis using 212 specimens and 34 characters indicated that P. hirsutum and P. setaceum are each morphologically distinct while P. hydropiperoides and P. opelousanum are morphologically indistinct from one another. The chromosome counts of 2n = 20 for P. setaceum and P. hirsutum, and 2n = 40 for P. hydropiperoides and P. opelousanum are the first reported for the respective species. Experimental hybridizations produced the fertile hybrids P. hydropiperoides x opelousanum and P. setaceum × hirsutum. Results of these studies and population structure, habitat, and pollination studies suggest that P. hydropiperoides, P. setaceum, and P. hirsutum are each distinct species while P. opelousanum is indistinct and should be merged with P. hydropiperoides.     

Morphotypes or distinct species? A multilocus assessment of two East Asian scimitar babblers (Aves,Timaliidae)

In birds, widespread species complexes often exhibit dramatic plumage differences across their distribution, which can give rise to discordance between morphotypes and phylogroups. Accurate identification of species diversity may require an integrated approach in which multilocus genetic data are used for inference and further corroborated by ecological, morphometric or behavioural data. Pomatorhinus gravivox and P. swinhoei, which were formerly considered component races of P. erythrogenys, were recently split using a delimitation system that mainly relied on the quantification of differences in phenotypic traits. We therefore carried out a reassessment of this taxonomic recommendation by conducting phylogenetic and population genetic analyses with multilocus genetic data. A deep mitochondrial split with a Kimura 2-parameter distance of 0.061 was observed, mainly corresponding to the two morphologically defined species. However, one individual from P. swinhoei harboured a haplotype of P. gravivox. Individual-based analyses of nuclear loci identified two distinct clusters that were exactly congruent with the two species. BPP delimitation also provided support for the separation. These congruencies support the notion that these two taxa are best regarded as two separate species. The presence of the P. gravivox mitochondrial haplotype in P. swinhoei was most likely a result of hybridization, due to the clear separation of nuclear loci. The speciation might be attributed to paleoclimatic changes but requires further evaluation due to the likelihood of ecological speciation. This study was in accordance with the results inferred from the quantitative system but highlighted the importance of sampling various data, especially in contact zones, in the study of taxonomy and speciation history.     

The physiological arms race: Exploring thermal acclimation among interacting species

Thermal acclimation is often expected to increase performance during survival-related interactions, such as prey-capture and predator escape. However, few studies have examined acclimation responses in the context of the organism's ecology: namely, considering interactions among different species. In this study, we investigated the acclimation responses of three species of aquatic organisms from the same environment that simultaneously interact across different seasons. We predicted that the crimson spotted rainbowfish (Melanotaenia duboulayi) and the freshwater shrimp (Paratya australiensis), which are involved in a predator–prey relationship, would exhibit similar thermal acclimation responses due to an arms race in physiological responses. In contrast, we expected that the backswimmer (Enithares sp.) species from the same environment, which is not commonly preyed upon due to their hard chitinous exterior, would display a limited acclimation response. We found that acute increases in temperature resulted in improved locomotor performance for all three species and an improved prey capture performance for M. duboulayi. Acclimation to 15 °C or 25 °C for 6 weeks did not affect the prey-capture performance of M. duboulayi or the locomotor performance of either M. duboulayi or Enithares sp. However, acclimation to cool temperatures improved the locomotor performance of P. australiensis at both cool and warm temperatures. Thus, the interaction between M. duboulayi (predator) and P. australiensis (prey) is likely to change across seasons via differences in acclimation responses, which could directly affect their behavioural strategies and population dynamics.     

In situ video monitoring of by-catch interactions within commercial rock lobster (Jasus edwardsii) fishing traps

The incidental capture of non-target and undersized target species during commercial fishing operations has been identified as a major issue and ongoing challenge for fisheries management. In the Northern Zone rock lobster (Jasus edwardsii) fishery (NZRLF) of South Australia, escape gaps have been mandatory in all commercial fishing traps since 2002 to reduce non-target species (by-catch) catch rates and juvenile lobster mortality. This study used in situ video monitoring of by-catch species in traps with and without escape gaps to understand how by-catch species interact within commercial fishing traps. Twenty-two different by-catch species were observed entering commercial rock lobster traps, 20 of which were temperate reef finfish. Overall, on-board by-catch rates were significantly higher in hauled traps without escape gaps and were dominated by reef-dwelling finfish species, particularly Meuschenia hippocrepis and Notolabrus tetricus. However, in situ video monitoring within traps showed no difference in the maximum number of finfish by-catch (MaxN) in traps with or without escape gaps. We suggest that the difference in by-catch rates between hauled traps with and without escape gaps may be driven by species-specific behavioural interactions within traps prior to hauling. Overall, this study shows that the implementation of escape gaps in the NZRLF has considerably reduced fishery by-catch rates. Furthermore, the use of in situ video monitoring has provided a better understanding of by-catch behavioural interactions within traps, not previously identified in on-board sampling research, which may partly explain the mechanisms underpinning escape gap effectiveness.     

Comparative Feeding Ecology of Sympatric <Emphasis Type="Italic">Microcebus berthae and M. murinus</Emphasis>

Most Malagasy primate communities harbor a diverse assemblage of omnivorous species. The mechanisms allowing the coexistence of closely related species are poorly understood, partly because only preliminary data on the feeding ecology of most species are available. We provide an exemplary feeding ecology data set to illuminate coexistence mechanisms between sympatric gray and Madame Berthe’s mouse lemurs (Microcebus murinus, M. berthae). We studied their feeding ecology in Kirindy Forest/CFPF, a highly seasonal dry deciduous forest in western Madagascar. Between August 2002 and December 2007, we regularly (re-)captured, marked, and radiotracked females of both species. A combination of direct behavioral observations and fecal analyses revealed that both Microcebus species used fruit, arthropods, gum, insect secretions, and small vertebrates as food sources. However, Microcebus berthae and M. murinus differed in both composition and seasonal variation of their diets. Whereas the diet of Microcebus murinus varied seasonally and was generally more diverse, M. berthae relied mainly on insect secretions supplemented by animal matter. The differences were also reflected in a very narrow feeding niche of Microcebus berthae and a comparatively broad feeding niche of M. murinus. Resource use patterns of Madame Berthe’s and more so of opportunistic gray mouse lemurs broadly followed resource availability within the strongly seasonal dry forest. Feeding niche overlap between the 2 sympatric species was high, indicating that food resource usage patterns did not reflect niche partitioning, but can instead be explained by constraints due to food availability.     

The biology and ecology of the ocean sunfish <Emphasis Type="Italic">Mola mola</Emphasis>: a review of current knowledge and future research perspectives

Relatively little is known about the biology and ecology of the world’s largest (heaviest) bony fish, the ocean sunfish Mola mola, despite its worldwide occurrence in temperate and tropical seas. Studies are now emerging that require many common perceptions about sunfish behaviour and ecology to be re-examined. Indeed, the long-held view that ocean sunfish are an inactive, passively drifting species seems to be entirely misplaced. Technological advances in marine telemetry are revealing distinct behavioural patterns and protracted seasonal movements. Extensive forays by ocean sunfish into the deep ocean have been documented and broad-scale surveys, together with molecular and laboratory based techniques, are addressing the connectivity and trophic role of these animals. These emerging molecular and movement studies suggest that local distinct populations may be prone to depletion through bycatch in commercial fisheries. Rising interest in ocean sunfish, highlighted by the increase in recent publications, warrants a thorough review of the biology and ecology of this species. Here we review the taxonomy, morphology, geography, diet, locomotion, vision, movements, foraging ecology, reproduction and species interactions of M. mola. We present a summary of current conservation issues and suggest methods for addressing fundamental gaps in our knowledge.     

Symbiodinium population genetics: testing for species boundaries and analysing samples with mixed genotypes

Population genetic markers are increasingly being used to study the diversity, ecology and evolution of Symbiodinium, a group of eukaryotic microbes that are often mutualistic with reef‐building corals. Population genetic markers can resolve individual clones, or strains, from samples of host tissue; however, samples may comprise different species that may confound interpretations of gene flow and genetic structure. Here, we propose a method for resolving species from population genetic data using tests for genetic recombination. Assigning individuals to genetically recombining populations prior to further analyses avoids critical errors in the interpretation of gene flow and dispersal. To demonstrate the effectiveness of the approach, we first apply this method to a simulated data set. We then use the method to resolve two species of host generalist Symbiodinium that commonly co‐occur in reef‐building corals collected from Indo‐West Pacific reefs. We demonstrate that the method is robust even when some hosts contain genotypes from two distinct species. Finally, we examine population genetic data sets from two recently published papers in Molecular Ecology. We show that each strongly supports a two species interpretation, which significantly changes the original conclusions presented in these studies. When combined with available phylogenetic and ecological evidence, the use of population genetic data offers a robust method for unambiguously delimiting morphologically cryptic species.     

A revision of West Palaearctic species of the Micropsectra atrofasciata species group (Diptera: Chironomidae)

Phylogenetic relations among selected Micropsectra (Diptera: Chironomidae) species are inferred using mitochondrial COII gene sequences and morphological characters. Both maximum parsimony and Bayesian analyses indicate a monophyletic atrofasciata species group. However, some species morphologically similar to M. atrofasciata (Kieffer) in the adult male, i.e. M. appendica sp. nov. and M. logani (Johannsen), are placed outside the atrofasciata group in the gene trees. The phylogenetic hypotheses based on parsimony analyses of the combined molecular and morphological data sets weakly support a monophyletic atrofasciata group including M. appendica sp. nov. and M. logani if third positions in the COII gene sequences are excluded. In the taxonomic part of this study, adult males, pupae and larvae of Micropsectra aristata Pinder, M. atrofasciata, M. bavarica sp. nov., M. klinki sp. nov., M. logani, M. pallidula (Meigen) and M. schrankelae sp. nov. , and adult males and pupae of M. appendica sp. nov. and M. sofiae sp. nov. as well as adult males of M. andalusiaca Marcuzzi, M. calcifontis sp. nov., M. freyi Storå, M. longicrista sp. nov., M. robusta sp. nov. , and M. zernyi Marcuzzi are described and diagnosed. Micropsectra bidentata (Goetghebuer), M. jokaquarta Sasa & Ogata, M. miki Marcuzzi, M. pallida Goetghebuer, M. subnitens Goetghebuer, M. suecica (Kieffer) and M. shouharasima Sasa are new junior synonyms of M. atrofasciata; Micropsectra groenlandica Andersen and M. utonaitertia Sasa are new junior synonyms of M. logani; Micropsectra candida Chaudhuri & Datta, M. franzi Goetghebuer and M. viridiscutellata Goetghebuer are new junior synonyms of M. pallidula. Comments on the ecology, distribution and systematics of each species are provided. Keys to all known life stages are presented, as well as an annotated list of species morphologically similar to species in the atrofasciata group and nomina dubia in the atrofasciata group. Chironomus mimulus Holmgren is transferred to the genus Micropsectra. © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society, 2006, 146 , 165–225.     

A multiple‐gene phylogeny reveals polyphyly among eastern North American Aphaenogaster species (Hymenoptera: Formicidae)

Twenty‐three Aphaenogaster species (Hymenoptera: Formicidae) occur in North America. While morphology and ecology define most species, the species limits of a group in the Eastern United States are unclear. In particular, the morphological and behavioural characters of A. carolinensis, A. picea and A. rudis overlap. These observations suggest that these three species are not monophyletic. We therefore tested the monophyly of Aphaenogaster in the context of molecular phylogenetic analyses. We used DNA data from five genes: CO1, CAD, EF1αF2, long‐wavelength rhodopsin and wingless, to reconstruct phylogenies for 44 Aphaenogaster and outgroup species. In the resulting trees, reconstructed using parsimony and Bayesian inference, species boundaries associated with well‐supported monophyletic clades of individuals in most of the 23 North American Aphaenogaster collected from multiple locations. However, some clades were unresolved, and both A. picea and A. rudis were not monophyletic. Although this may indicate that clades of multiple species represent fewer but morphologically varied species, given the short branch lengths, the lack of resolution may reflect the fact that these ants have recently radiated, and a lack of gene lineage sorting explains the non‐monophyly of species. Additional biological information concerning pre‐ and postmating barriers is needed before a complete revision of species boundaries for Aphaenogaster.     

Habitat requirements and niche selection of Maculinea nausithous and M. teleius (Lepidoptera: Lycaenidae) within a large sympatric metapopulation

Identifying the factors determining the distribution and abundance of species is a fundamental question in population ecology. Based on habitat characteristics, we sought to identify factors affecting the abundance of two vulnerable large blue butterflies, Maculinea teleius and Maculinea nausithous. Both species often occur in sympatry and thus seem to have very similar requirements with regard to their wetland habitats. Even though, M. nausithous is usually far more widespread and abundant than M. teleius in Central Europe. For understanding this difference despite a similar ecology, more data is needed on the niche selection of both species. We have recorded Maculinea numbers, vegetation structure, food-plant abundance and ant community for 120 patches within a large sympatric metapopulation of both species in the Westerwald area (Germany). Unexpectedly (based on previous data), both species were equally common in the study area, reaching high densities of up to 61 (M. teleius) and 58 (M. nausithous) individuals per 50 m2. In 116 out of 120 patches both species occurred sympatrically. The preferred habitat was extensively managed grassland, being mown or grazed twice a year. The abundance of both Maculinea species was positively related to vegetation height, food-plant and Myrmica rubra abundance. There was no association between M. teleius and its putative main host-ant Myrmica scabrinodis, indicating that M. rubra may serve as an important host in the Westerwald area. The positive effect of food-plant abundance was more pronounced for M. teleius, coinciding with a higher food-plant abundance at sites dominated by M. teleius compared to those dominated by M. nausithous. Thus, M. teleius seems to be slightly more demanding than M. nausithous in terms of food-plant availability.     

Feeding and oviposition preference of the Sakhalin pine sawyer Monochamus saltuarius (Coleoptera: Cerambycidae) for various tree species

Monochamus saltuarius was recently identified as an important vector of Bursaphelenchus xylophilus, the cause of pine wilt disease. In this study, M. saltuarius adults preferred different species of tree based on the longevity, ingested amount and wounded area that were determined for 90 d. Among eight tree species, the longevity of feeding by M. saltuarius was not significantly different except when feeding in Sciadopitys verticillata. However, the highest ingested amounts with the largest wounded areas were associated with Pinus koraiensis. The highest oviposition preference was in P. densiflora for the first 20 d. However, after 40 d, the oviposition highest preference was noted in P. koraiensis. For oviposition activities, M. saltuarius preferred the tree species in the following order: P. densiflora > P. koraiensis > P. rigida > Larix leptolepis. Although many oviposition scars were observed, M. saltuarius laid fewer eggs in P. rigida than other species of pine, which was related to the bark thickness. The oviposition frequencies were highest with bark 2.0–2.5 mm thick and with tree diameters of 110–130 mm. The current study increased understanding of the ecology of M. saltuarius by identifying specific tree preferences.     

A new Ceratium species (Dinophyceae) from Lake Doïrani,Macedonia, Greece

A new taxon of Ceratium is described from Lake Doïrani, Greece. It is proposed as a new species and named Ceratium monoceras. It differs morphologically from known species of Ceratium by having only one horn, the apical horn. Accordingly, the vegetative cells form cysts that have only one spine. Details of its ecology and occurence are given.     

Associations in the midwater zone: The penaeid shrimp funchalia sagamiensis fujino 1975 and pelagic tunicates (order: Pyrosomatida)

An association between the penaeid shrimp Funchalia sagamiensis FUJINO 1975 and pelagic tunicates of the Order Pyrosomatida was confirmed through in situ submersible and shipboard observations. Information on this association, including behavioural, morphological and distributional data is presented. The association is “strong”;, possibly obligate for the shrimp during this life‐history phase, and does not appear to be species‐specific. Further information is presented on the taxonomic standing within the genus Funchalia of the enigmatic species F. sagamiensis. The utility of submersibles for in situ behavioural research is discussed.     

A review of the biology and ecology of the Robber Crab, Birgus latro (Linnaeus, 1767) (Anomura: Coenobitidae)

Birgus latro (L.) is the largest terrestrial hermit crab in the world. The species is widely distributed on remote Indo-Pacific islands of the tropics, but it is rapidly declining and is currently classified as data deficient on the IUCN red list. This review provides a synopsis of both published and unpublished data on the biology and ecology of B. latro. It highlights the lack of robust biological information on the species’ basic biology, particularly in the juvenile and reproductive phases, while behavioural ecology studies are few and report conflicting data between populations. Population studies indicate that B. latro may have limited recruitment events throughout its range, emphasising the need for more systematic research to clearly identify factors that influence successful recruitment events. The review highlights the paucity of substantiated peer reviewed studies on this species and emphasises the need for further systematic research.     

Phylogenetic relationships on 14 morphologically similar species of Pucciniastrum in Japan based on rDNA sequence data

We analyzed the phylogenetic relationships of 49 specimens comprising 14 morphologically similar species of Pucciniastrum distributed in Japan based on the sequence data of the large subunit rDNA (D1/D2), 5.8S rDNA, and internal transcribed spacer (ITS) regions. Neighbor-joining and parsimony analyses generated six major groups for both the D1/D2 and ITS regions. Pucciniastrum circaeae and P. epilobii formed a single group. P. hydrangeae-petiolaris, P. coryli, P. fagi, P. hikosanense, P. tiliae, and P. boehmeriae were each a distinct clade, and P. fagi formed a close relationship with P. hikosanense. However, these analyses did not support the monophyly of the following species: P. kusanoi, P. actinidiae, P. corni, P. styracinum, P. yoshinagai, and P. miyabeanum. Contribution no. 201, Laboratory of Plant Parasitic Mycology, Graduate School of Life and Environmental Sciences, University of Tsukuba, Japan