DNA‐based species delimitation separates highly divergent populations within morphologically coherent clades of poorly dispersing beetles

We compared species‐level entities recovered using distance, tree‐based, and DNA‐character based methods with morphologically defined species in poorly dispersing lyponiine net‐winged beetles. The phylogenetic relationships were investigated using the cytochrome c oxidase 1–2 mtDNA fragment. We identified 31 species using a morphology‐based concept and additional candidate species were delimited by the general mixed Yule‐coalescent method and barcoding threshold within the morphologically coherent lineages owing to high genetic divergence (up to 10.97% within morphologically defined species, highest density 2.5–6.5%). Genetic divergence was positively correlated with geographical distance: lower in continental China where no apparent dispersal barriers are present (r² = 0.172, P ≤ 0.001, average increase of genetic distance of 0.32% per 100 km) and much higher in Japan (r² = 0.490, P ≤ 0.001, 1.81% per 100 km). We hypothesize that low dispersal propensity contributed to the high level of intraspecific, geographically structured divergence. DNA‐based methods suggested a high number of morphologically undistinguishable species. The observed patterns agree with the model of neutral evolution. The poor dispersers produce gradually divergent populations across the range of the morphologically coherent lineages. We pose the question of what size of range and level of genetic difference justify formal acceptance of a species without morphological divergence from both the taxonomical and conservation management view points. © 2015 The Linnean Society of London     

Disentangling relationships within the disjunctly distributed Alyssum ovirense/A. wulfenianum group (Brassicaceae), including description of a novel species from the north‐eastern Alps

Alyssum ovirense (Brassicaceae) is disjunctly distributed in the eastern Alps, predominantly occurring in the southern limestone Alps, but with one isolated population on the Hochschwab massif in the northern limestone Alps. The closely related rare and narrow endemic A. wulfenianum is restricted to gravel beds in a few rivers in the southern Alps draining the distribution area of A. ovirense. Applying molecular (amplified fragment length polymorphism fingerprinting and sequencing of plastid and nuclear DNA), karyological (flow cytometry and chromosome counts) and morphometric methods to a set of populations sampled throughout the distribution range, we evaluated the status of the population on the Hochschwab massif and the relationship between high‐elevation A. ovirense and low‐elevation A. wulfenianum. The population on Hochschwab massif is hexaploid, morphologically clearly divergent and grows in vegetation patches and dense alpine grasslands, whereas southern Alpine A. ovirense inhabits sparsely vegetated limestone screes. Molecular data show that the former represents a genetically isolated lineage which is formally described as A . neglectum sp. nov. All populations from the southern limestone Alps, including A. wulfenianum, are diploid. Although A. wulfenianum is genetically nested in A. ovirense, its morphological and ecological differentiation justifies recognition at the subspecific level. As A. wulfenianum has priority over A. ovirense, the correct names are A. wulfenianum subsp. wulfenianum and A. wulfenianum subsp. ovirense. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 176 , 486–505.     

云南东南部苦苣苔科植物一新种——南溪蛛毛苣苔

中越边境的石灰岩地区不仅具有较丰富的植物多样性,而且特有现象十分突出。该文描述了中越边境石灰岩地区位于云南东南部河口境内的苦苣苔科一个植物新种——南溪蛛毛苣苔(Paraboea nanxiensis Lei Cai & Gui L. Zhang)。该新种在叶片的形状和毛被、花的颜色、花序短于叶片以及雌蕊无毛等性状上与产自广西那坡的垂花蛛毛苣苔(P. nutans D. Fang & D. H. Qin)最为相似。两者的主要区别在于:该新种的花萼裂片先端最宽且光滑无毛,花冠浅宽钟形、花冠筒不明显、花冠管内面基部白色,花丝无毛以及蒴果稍微扭曲; 该新种生于云南海拔530～610 m的河口及马关一带,而垂花蛛毛苣苔产于广西那坡的海拔900～1 150 m段的石灰山。此外还讨论了该新种与蛛毛苣苔属其他几种基生叶类型的近缘种[如三萼蛛毛苣苔(P. trisepala W. H. Chen & Y. M. Shui)、蔓耗蛛毛苣苔(P. manhaoensis Y. M. Shui & W. H. Chen)及河口蛛毛苣苔(P. hekouensis Y. M. Shui & W. H. Chen)]的区别,并提供了相关物种的彩色图片及区分说明,主模式标本存放于中国科学院昆明植物研究所标本馆(KUN)中。近年来,由于中越边境的石灰岩地区不断有新分类群或新记录物种的发现,所以很有必要加强对该区域的植物多样性考察。     

Intercontinental dispersal: The origin of the widespread South American plant speciesGilia laciniata (Polemoniaceae) from a rare California and Oregon coastal endemic

Although separated by 7000-km,Gilia millefoliata, a rare annual plant from California and Oregon coastal dunes andG. valdiviensis, a rare Chilean coastal endemic are morphologically and ecologically quite similar. Their disjunct distribution was proposed to result from recent, birdmediated, intercontinental long-distance dispersal. Both species are morphologically similar to the abundant and ecologically diverse South American taxonG. laciniata. The relationship among these three taxa was investigated using DNA sequence from the nuclear ribosomal (ITS) and chloroplasttrnL regions, as well as isozyme and morphological variation to determine the roles of long-distance dispersal and ecological adaptation in the evolution of the group. These data suggest that aG. millefoliata-like ancestor underwent long-distance dispersal to South America, and there gave rise to the narrow endemicG. valdiviensis and the widespreadG. laciniata.     

Metapopulation structure of the marine isopod <Emphasis Type="Italic">Idotea metallica</Emphasis>, a species associated with drifting habitat patches

The neustonic isopod Idotea metallica inhabits objects drifting at the sea surface. Animals found on floating patches represent not just ephemeral assemblages but persistent local populations. Drift material collected in the Mediterranean, the North Atlantic, and the North Sea harboured populations of up to about 50 animals including all developmental stages. In laboratory experiments the species proved to be able to establish populations on spatially limited, isolated substrates. The capacity of 5-litre-microcosms for I. metallica was about 130 animals. In the presence of the coastally distributed congener Idotea baltica, however, laboratory populations of I. metallica went extinct within 12 weeks. Even though high colonisation rates can be expected in coastal waters because of high patch densities, metapopulation persistence is mostly restricted to the open sea. In coastal waters extinction rate of local populations increases because of patch destruction and the species' inferiority to coastally distributed competitors. Due to high uncertainties in estimating patch densities, it is difficult to determine the parameters underlying metapopulation dynamics such as the migration rate and the rate of patch occupancy. Electronic Publication     

The giant cryptic amphipod species of the subterranean genus Niphargus (Crustacea,Amphipoda)

Amphipods from the genus Niphargus represent an important part of the Western Palearctic subterranean fauna. The genus is morphologically diverse, comprising several distinct ecomorphs bound to microhabitats in the subterranean environment. The most impressive among them are “lake giants,” a series of massive, large‐bodied species. These range from morphologically distinct to morphologically cryptic taxa. We analysed the taxonomic structure of the Niphargus arbiter–Niphargus salonitanus species complex, belonging to “lake giants” from the Dinaric Karst (West Balkans), and assessed their phylogenetic, morphological and ecological diversity. Multilocus phylogeny suggested that the complex is monophyletic and nested within other cave lake ecomorphs. Unilocus and multilocus coalescence species delimitations indicated that the complex totals nine species. These species substantially overlap in morphology and cannot be unambiguously told apart without the use of molecular markers. An analysis of splitting events within a palaeogeological context, and modelling of environmental characteristics on the phylogeny unveiled a complex history of diversification. Part of this diversification might have been influenced by ecological divergence along the altitudinal gradient reaching from the Adriatic coast to inland Dinaric mountain chains and Poljes. Other splits coincide with the marine regression–transgression cycles during Pliocene. We describe Niphargus alpheus sp. n., Niphargus anchialinus sp. n., Niphargus antipodes sp. n., Niphargus arethusa sp. n., Niphargus doli sp. n., Niphargus fjakae sp. n. and Niphargus pincinovae sp. n., and by doing so hope to prompt their further research.     

Daphnia (Ctenodaphnia) hispanica sp. nov., a new daphnid (Cladocera) from Spain

Daphnia (C.) hispanica n. sp. has thoracic limbs of A D. (C.) atkinsoni type and is very similar toD. chevreuxi Richard, 1896. With this speciesD. (C.) hispanica shares the presence of a soft accessory seta on the outer side of the trunk of the first thoracic limb, apparently unique among the genusDaphnia. Although other morphological characteristics are very similar in this two species, a detailed comparison reveals that they can easily be separated as different species. The most useful features in differentiating both species are:D. (C.) hispanica has a dorsal crest in the head, its rostrum is longer, its accesory seta of the first thoracic limb is more developed, the juveniles are not helmeted and its male postabdomen lacks individual denticles on the anal and preanal margin.The new species is, up to now, restricted to Spain and inhabits the temporary and low mineralized waters of the steppe regions.     

A new species ofNeosartorya from Taiwan soil

A new species ofNeosartorya, N. multiplicata (anam.Aspergillus multiplicatus), isolated from soil collected at Houli, Taichung, in Taiwan, is described and illustrated. The species is characterized by its restricted growth on Czapek agar, white ascomata, nearly globose ascospores with ribbed surface ornamentation of several linear ridges, and a limited development of conidia on common media. A key to all accepted species of the genus is provided.     

On the habitats,distribution and life-cycles of the Western European species of the genus Helochares Mulsant (Coleoptera: Hydrophilidae)

Adult water beetles were collected from 841 localities in the Netherlands. The distribution maps of the three species of the genus Helochares (Coleoptera; Hydrophilidae) in the Netherlands are given. They are based on specimens from museum collections and this investigation. H. lividus occurs all over the Netherlands, except for the north-east. This northern limit of its European distribution area coincides with the 8.5°C isotherm for the mean year temperature. H. obscurus is limited in its distribution to clay and peat-bog, but in the sandy coastal dune area H. obscurus replaces H. punctatus. H. punctatus is limited in its distribution to soils consisting of peat-moor or sand, but it is absent from the coastal dune area.Co-existence of H. lividus with either H. obscurus or H. punctatus occurs regularly. Co-existence of H. obscurus and H. punctatus has been observed only once, these species exclude each other by different ecological requirements. H. lividus and H. obscurus show two optima in abundance during the year which corresponds with a univoltine life-cycle. H. punctatus shows no clear maximum in abundance. However, on the basis of the presence of females carrying egg-cases and the presence of teneral adults a univoltine life-cycle for all three Helochares spp. can be deduced. A small proportion of the beetles hibernates either as larva or as pupa and emerges in spring.The distribution of Helochares spp. has been related to some environmental variables using the Index of Representation. H. lividus has a clear preference for waters with a high pH, high conductivity and high chlorinity with a luxurious vegetation of floating leaved and submerged plants on mineral soils. Occasionally running waters or waters with a low current velocity are preferred. Preferred habitats are regulated lowland streams, clay- and sand-ditches, and clay- and sand-canals. H. obscurus has a clear preference for stagnant waters with a high pH, high conductivity and high chlorinity (but the optimum is lower than for H. lividus) with a luxurious vegetation of floating leaved and submerged plants. Preferred habitats are clay- and sand-ditches. H. punctatus has a very clear preference for waters with a low pH, low conductivity and low chlorinity. With respect to vegetation and type of current the species shows no significant preferences or aversions. Preferred habitats are moorland pools, peat-canals and peat-cuttings.     

A new species of Castilleja (Orobanchaceae) from central Hidalgo, Mexico

Castilleja hidalgensis is described from several collections from xeric limestone sites in central Hidalgo, Mexico. The new species belongs to a small complex of poorly known and uncommon species within sect.Euchroma, sharing important characteristics withC. macrostigma, the first-described taxon in this assemblage. The new species appears to be rare and highly restricted both geographically and ecologically. A key to the species of theC. macrostigma group is provided.     

Cardamine apennina: a new endemic diploid species of the C. pratensis group (Brassicaceae) from Italy

Italian representatives of the Cardamine pratensis group were investigated using morphometric, karyological, and molecular (AFLP-fingerprinting) analyses. Focus was on resolving the taxonomic and evolutionary position of C. granulosa from Piemonte (NW Italy) and of populations from central Italy, previously included in C. granulosa or C. pratensis s. str. Results show that C. granulosa is a morphologically and genetically well defined diploid species, but is extremely rare and restricted to a small area in Piemonte. Central Italian populations differ from both C. granulosa and C. pratensis s. str., and, although the morphological differentiation is not strongly pronounced, they show marked molecular divergence, suggesting recognition as a new species, Cardamine apennina. Because of their restricted distribution and diploid chromosomal level, C. apennina and C. granulosa may represent basal and quite isolated lineages, whereas reticulation on diploid and polyploid level has affected remaining lineages of the C. pratensis group. Both Italian endemics are endangered due to rarity and habitat loss. A key for identification of the Italian taxa of the C. pratensis group is also provided.     

Genetic variation in Simocephalus (Anomopoda: Daphniidae) in North America: patterns and consequences

The presumption of intercontinental distributions of many species of Anomopoda has been reinforced by their considerable morphological uniformity and ease of passive dispersal via ephippial eggs. To test the validity of this dogma, genetic variation among taxa in the cladoceran genus Simocephalus was examined on a continental scale. Genetic variability (percentage polymorphic loci = 8.8%, individual heterozygosity = 3.4%) was comparable to that determined on a local scale in Simocephalus and somewhat less than for other zooplankton groups. Four species complexes were distinguished allozymically with unique allelic substitutions found for at least two loci between these taxa. Eight species in North America were differentiated within these complexes (Nei s genetic distance, D>0.30), all of which were clearly separated from two European species. Both S. cf. vetulus and S. cf. serrulatus are broadly distributed in North America, and intraspecific divergence is relatively low. In contrast, S. cf. congener and S. cf. exspinosus represent species complexes, both consisting of several species, differentiated allozymically and morphologically. The concept of generalist species with moderate genetic variation throughout a broad range and specialist species, genetically depauperate, with restricted distributions, is explored.     

Hierarchical population structure and habitat differences in a highly mobile marine species: the Atlantic spotted dolphin

Recent molecular studies have shown that highly mobile species with continuous distributions can exhibit fine‐scale population structure. In this context, we assessed genetic structure within a marine species with high dispersal potential, the Atlantic spotted dolphin (Stenella frontalis). Using 19 microsatellite loci and mitochondrial control region sequences, population structure was investigated in the western North Atlantic, the Gulf of Mexico and the Azores Islands. Analyses of the microsatellite data identified four distinct genetic clusters, which were supported by the control region sequences. The highest level of divergence was seen between two clusters corresponding to previously described morphotypes that inhabit oceanic and shelf waters. The combined morphological and genetic evidence suggests these two lineages are on distinct evolutionary trajectories and could be considered distinct subspecies despite their parapatry. Further analysis of the continental shelf cluster resulted in three groups: animals inhabiting shelf waters in the western North Atlantic, the eastern Gulf of Mexico and the western Gulf of Mexico. Analyses of environmental data indicate the four genetic clusters inhabit distinct habitats in terms of depth and sea surface temperature. Contemporary dispersal rate estimates suggest all of these populations should be considered as distinct management units. Conversely, no significant genetic differentiation was observed between S. frontalis from offshore waters of the western North Atlantic and the Azores, which are separated by approximately 4500 km. Overall, the hierarchical structure observed within the Atlantic spotted dolphin shows that the biogeography of the species is complex because it is not shaped solely by geographic distance.     

Branchipodopsis species — specialists of ephemeral rock pools

The anostracan Branchipodopsis genus is widespread throughout southern Africa and is the second most speciose anostracan taxon in this sub-continent. Branchipodopsis species are particularly dominant in small short-lived and clear rock pools, to the vagaries of which they are extremely well adapted. Such rock pools were studied in the Drakensberg region, in the eastern Free State and in south-eastern Botswana. Common features of Branchipodopsis-inhabited rock pools are the transparency of the water and the very low conductivity values (generally below 50μScm^?1, often less than 10μScm^?1). These shallow (usually less than 50cm) water bodies with limited buffering capacity show major fluctuations in pH values (often between about pH 4 and 11), depending on the time of the day and the stage in the hydrocycle. Rock pools also closely follow ambient air temperatures with resulting fluctuations of values between 10 and 40°C. Depending on local climatic conditions, small rock pools are usually short-lived and have several wet/dry cycles during one rainy season. Branchipodopsis species are the record-holders in this race against time with maturation usually being reached within the first week after inundation. Broods of resting eggs are generally small (less than 80 eggs) but are produced almost daily. Often (in 30% of cases in south-eastern Botswana), erratic rainfall does not allow sufficient time for successful maturation and reproduction. As a safe-guarding mechanism in B. wolfi in south-eastern Botswana, only some of the eggs hatch on each occasion, depending on environmental conditions, thus extending the chances for successful recruitment. While short-range dispersal of floating eggs by overflows is common, long-range dispersal (e.g. by wind) seems to be rare and to be restricted to shallow pools with little vegetation. Limited effective dispersal may explain the high number of endemic species (e.g. four in the Drakensberg region) and the large morphological variation in some widespread species such as B. wolfi.     

Spatial structure and genetic diversity of three tropical tree species with different habitat preferences within a natural forest

Analyses of the spatial distribution pattern, spatial genetic structure and genetic diversity were carried out using a 33-ha plot in a hill dipterocarp forest for three dipterocarps with different habitat preferences, i.e. Shorea curtisii on the ridges, Shorea leprosula in the valleys and Shorea macroptera both on the ridges and in the valleys. The significant spatial aggregation in small-diameter trees of all the three species was explained by limited seed dispersal. At the large-diameter trees, only S. macroptera showed random distribution and this might further prove that S. macroptera is habitat generalist, whilst S. curtisii and S. leprosula are habitat specific. The levels of genetic diversity estimated based on five microsatellite loci were high and comparable in all the three studied species. As the three studied species reproduced mainly through outcrossing, the observed high levels of genetic diversity might support the fact that the plant mating system can be used as guideline to infer the levels of genetic diversity, regardless of whether the species is habitat specific or habitat generalist. The lack of spatial genetic structure but significant aggregation in the small-diameter trees of all the three species might indicate limited seed dispersal but extensive pollen flow. Hence, if seed dispersal is restricted but pollen flow is extensive, significant spatial aggregation but no spatial genetic structure will be observed at the small-diameter trees, regardless of whether the species is habitat specific or habitat generalist. The inferred extensive pollen flow might indicate that energetic pollinators are involved in the pollination of Shorea species in the hill dipterocarp forests.     

Serological relationships of Fraction I proteins from species in the genusNicotiana

The serological relationships of Fraction I proteins from 62 species of the genusNicotiana have been determined by qualitative double diffusion in agar gels, using antisera raised against crystalline Fraction I proteins from four species,N. glauca, N. glutinosa, N. gossei, andN. tabacum. The relationships obtained are, in most cases, similar to the relationships of the species based on morphological and cytogenetic criteria. In general, Fraction I proteins from species within the same section are serologically identical. However, serological examination of Fraction I proteins draws attention to certain species, for example,N. glauca, N. sylvestris, andN. acaulis, whose classification by traditional methods has been difficult.     

Morphological recognition of cryptic species in the planktonic foraminifer Orbulina universa

One of the key hypotheses of paleoceanography is that planktonic foraminiferal morphospecies record reasonably stable and homogeneous oceanographic and climatic characteristics over their geographic and stratigraphic ranges. The discovery of numerous genetically-defined cryptic species challenges the morphospecies concept in planktonic foraminifera and paleoceanographic interpretations based on them. Here, we present a combined genetic and biometric analysis of Orbulina universa specimens in the Atlantic, Indian and Pacific Oceans. Our study is based on shells retained after DNA extractions. On those genotyped shells, we perform biometric analyses (shell size and thickness, inner porosity and pore surface distribution). Our genetic data confirm the presence of three cryptic species of O. universa in the world ocean, whose distributions are primarily correlated to the productivity of the surface waters. The Mediterranean species of O. universa is most abundant in the vertically mixed and nutrient-rich areas of the low to mid-latitudes, whereas the Caribbean and Sargasso species occur in stratified and oligotrophic subtropical waters. Our biometric data show no correlation between shell size and inner porosity within each cryptic species of O. universa. Combining Principal Component Analyses with MANOVAs performed on shell pore surface distribution, we demonstrate that the three different cryptic species are characterized by significant morphological differentiation. The Caribbean species typically exhibits large pores and higher porosity values, while the Mediterranean and Sargasso species are characterized by smaller pore areas and shell porosity. A model based upon pore surface distribution correctly assigns 60% to 90% of the specimens to their corresponding genotype. Although the inner shell surface of the Sargasso species resembles that of the Mediterranean species, our model demonstrates that the pore surface distributions of these two cryptic species can be distinguished. Finally, the Sargasso species exhibits significantly thinner shells than the two other cryptic species.