Island Taxa Research Articles

Osteological and historical data on extinct island night herons (Aves: Ardeidae), with special reference to Ascension Island, the Mascarenes and Bonin Islands

Night herons of the genus Nycticorax and Nyctanassa are adept island colonisers, occurring on a number of oceanic islands and island archipelagos. Continental species and those inhabiting large islands are generally not considered threatened, whereas night herons restricted to small, oceanic islands are particularly vulnerable to human interference. As a result, six out of nine described species and one subspecies, all derived from Nycticorax nycticorax, Nycticorax caledonicus or Nyctanassa violacea, are now extinct whereas a further three extinct species await description. The extinct island endemics generally exhibit morphological adaptations to an insular environment and diet, such as an increase or decrease in size, robust jaws and legs, and smaller wings with associated reduced flying ability than founding stock. Here I present an osteological comparison along with historical descriptions of the extinct, oceanic island night herons, with special reference to the Mascarene and Ascension fossil species, and Bonin Island subspecies, and show the degree of morphological changes between the founding and island taxa. I further discuss the reasons why they became extinct.

Lineage diversity in a widely distributed New World passerine bird, the House Wren

Abstract We explored the evolutionary radiation in the House Wren complex (Troglodytes aedon and allies), the New World’s most widely distributed passerine species. The complex has been the source of ongoing taxonomic debate. To evaluate phenotypic variation in the House Wren complex, we collected 81,182 single-nucleotide polymorphisms (SNPs) from restriction site associated loci (RADseq) and mitochondrial DNA (mtDNA) from samples representing the taxonomic and geographic diversity of the complex. Both datasets reveal deep phylogeographic structuring, with several topological discrepancies. The trees highlight the evolutionary distinctiveness of eastern and western T. aedon, which were sister taxa in the SNP tree and paraphyletic on the mtDNA tree. The RADseq data reveal a distinct T. a. brunneicollis group, although STRUCTURE plots suggest admixture between western T. aedon and northern Mexican samples of T. a. brunneicollis. MtDNA data show a paraphyletic arrangement of T. a. musculus on the tree, whereas the SNP tree portrays them as monophyletic. Island taxa are distinct in both datasets, including T. a. beani (Isla Cozumel), which appears derived from T. a. musculus in eastern Mexico, and T. sissonii (Isla Socorro) and T. tanneri (Isla Clarión) although the 2 datasets disagree on their overall phylogenetic placement. Although we had only mtDNA data for T. a. martinicensis from the Lesser Antilles, we found at least 4 distinct and paraphyletic taxa from Trinidad, Granada, St. Vincent islands, and Dominica. The House Wren complex showed strong differentiation in mtDNA and RADseq datasets, with conflicting patterns likely arising from some combination of sex-biased dispersal, incomplete lineage sorting, or selection on mtDNA. The most glaring discrepancies between these 2 datasets, such as the paraphyly of eastern and western North American House Wrens in the mtDNA tree, present excellent opportunities for follow-up studies on evolutionary mechanisms that underpin phylogeographic patterns.

Genetic structure of the Japanese Robin (Larvivora akahige) endemic to East Asian islands

Geographical isolation is a key factor in allopatric speciation although divergence with gene flow has been detected in an increasing number of studies, even in island systems. To understand the divergence in island taxa, it is necessary to examine historical gene flow with mainland sister groups, which largely differ due to the various geological and ecological characteristics of each region. The Izu Islands are a chain of young and active volcanic islands in a warm‐temperate climate zone that branch off from the middle of the Japanese mainland. Despite the chain's relatively limited isolation, given its proximity to the mainland, the Izu Islands feature endemic bird species and subspecies. The Japanese Robin Larvivora akahige is an endemic breeder on East Asian islands, and there is also a subspecies on the Izu Islands that is different in feather coloration and ecological traits. The population genetic structure of this robin was investigated using nine nuclear microsatellite markers and mitochondrial cytochrome b region sequences. Distinct and recent differentiation between the groups from the Izu Islands and mainland was detected from nuclear loci, although the genetic structure within the mainland group was unclear over the 1900‐km habitat chain. The mitochondrial haplotypes were divided into two distant clades, one dominated throughout the robin's range and the other coexisting only on the Izu Islands as a minor type. Those clades were inferred to have diverged independent of the recent differentiation of the two nuclear clusters, although their origins and the mechanism underlying their distribution remain unclear. The geographical characteristics of the Izu Islands may have formed a moderate but long‐lasting barrier for gene flow and promoted speciation, as well as serving as refugia for the preservation of relict lineages, particularly for migratory species, which usually move along the mainland chain.

Largest-known fossil penguin provides insight into the early evolution of sphenisciform body size and flipper anatomy

AbstractRecent fossil discoveries from New Zealand have revealed a remarkably diverse assemblage of Paleocene stem group penguins. Here, we add to this growing record by describing nine new penguin specimens from the late Paleocene (upper Teurian local stage; 55.5–59.5 Ma) Moeraki Formation of the South Island, New Zealand. The largest specimen is assigned to a new species, Kumimanu fordycei n. sp., which may have been the largest penguin ever to have lived. Allometric regressions based on humerus length and humerus proximal width of extant penguins yield mean estimates of a live body mass in the range of 148.0 kg (95% CI: 132.5 kg–165.3 kg) and 159.7 kg (95% CI: 142.6 kg–178.8 kg), respectively, for Kumimanu fordycei. A second new species, Petradyptes stonehousei n. gen. n. sp., is represented by five specimens and was slightly larger than the extant emperor penguin Aptenodytes forsteri. Two small humeri represent an additional smaller unnamed penguin species. Parsimony and Bayesian phylogenetic analyses recover Kumimanu and Petradyptes crownward of the early Paleocene mainland NZ taxa Waimanu and Muriwaimanu, but stemward of the Chatham Island taxon Kupoupou. These analyses differ, however, in the placement of these two taxa relative to Sequiwaimanu, Crossvallia, and Kaiika. The massive size and placement of Kumimanu fordycei close to the root of the penguin tree provide additional support for a scenario in which penguins reached the upper limit of sphenisciform body size very early in their evolutionary history, while still retaining numerous plesiomorphic features of the flipper.UUID: https://zoobank.org/15b1d5b2-a5a0-4aa5-ba0a-8ef3b8461730

The Atlantic connection: coastal habitat favoured long distance dispersal and colonization of Azores and Madeira by Dysdera spiders (Araneae: Dysderidae)

The woodlouse hunter Dysdera spiders have colonized all Macaronesian archipelagos. We report here for the first time an evolutionary connection between the Iberian Peninsula, Madeira, and the remote archipelago of Azores. Based on museum specimens from the 1950s, we describe the first endemic Dysdera species from the Azores. Additionally, we report the recent collection of immature individuals related yet probably not conspecific to the new species, rejecting previous suggestions that the endemic lineage had gone extinct. A multi-locus target phylogeny revealed that an undescribed species from Madeira was the closest relative to the Azores lineage, and that both island taxa were in turn sister to an Iberian endemic species, within a mostly Iberian clade. Interestingly, the Madeiran relative was not closely related to the remaining endemic species reported in the archipelago, suggesting an independent colonization. A divergence time estimation analysis unravelled that Dysdera colonized both archipelagos early after their emergence. The colonization pathway remains ambiguous, but the Iberian Peninsula acted as the ultimate source of the ancestral colonizers. Finally, we describe the new species Dysdera cetophonorum Crespo & Arnedo sp. nov. from Pico and Dysdera citauca Crespo & Arnedo, sp. nov. from Ilhéu de Cima (Porto Santo) and redescribe and illustrate the female genitalia for the first time of their poorly known closest relative, Dysdera flavitarsis Simon, 1882 from the north-western Iberian Peninsula. http://zoobank.org/urn:lsid:zoobank.org:pub:1E75CCEC-1632-4581-93A5-E61721970022

Systematics and conservation of an endemic radiation ofAccipiterhawks in the Caribbean islands

AbstractMore than one-third of the bird species found in the Caribbean are endemic to a set of neighboring islands or a single island. However, we have little knowledge of the evolutionary history of the Caribbean avifauna, and the lack of phylogenetic studies limits our understanding of the extent of endemism in the region. The Sharp-shinned Hawk (Accipiter striatus) occurs widely across the Americas and includes 3 endemic Caribbean taxa: venator on Puerto Rico, striatus on Hispaniola, and fringilloides on Cuba. These island populations have undergone extreme declines presumably due to ecosystem changes caused by anthropogenic factors, as well as due to severe hurricanes. Sharp-shinned Hawks, in general, and Caribbean Sharp-shinned Hawks, in particular, have not been placed in a modern phylogenetic context. However, the island taxa have historically been presumed to have some ongoing gene flow with mainland populations. Here we sequenced ultraconserved elements (UCEs) and their flanking regions from 38 samples, focusing on Caribbean taxa. Using a combination of UCEs, mitochondrial genome sequences, and single-nucleotide polymorphisms, we investigated the phylogenetic relationships among Caribbean lineages and their relationships to mainland taxa. We found that Caribbean Sharp-shinned Hawks are reciprocally monophyletic in all datasets with regard to mainland populations and among island taxa (with no shared mtDNA haplotypes) and that divergence in the NADH dehydrogenase 2 gene (ND2) between these mainland and island groups averaged 1.83%. Furthermore, sparse non-negative matrix factorization (sNMF) analysis indicated that Hispaniola, Puerto Rico, and mainland samples each form separate populations with limited admixture. We argue that our findings are consistent with the recognition of the 3 resident Caribbean populations as species-level taxa because nuclear and mitochondrial genetic data indicate reciprocal monophyly and have species-level divergences, there is no sharing of mitochondrial haplotypes among or between island taxa and those on the mainland; and they are diagnosable by plumage.

Studies on Neotropical crickets: The continental Otteiini taxa (Orthoptera: Phalangopsidae), those cave crickets are not confined to the West Indies.

The tribe Otteiini is a group of cave crickets, that were believed only to inhabit the Greater Antilles (Cuba, Cayman Islands, and Hispaniola). However, when reviewing and studying similar cave crickets in Mexico, their relationship was proven with island taxa, expanding their distribution to the continental area, from the Yucatan Peninsula to the Gulf and Northeast of Mexico. Herein, the genus Paracophus is divided, and three additional genera are described: Hubbellcophus n. gen., Venegascophus n. gen. and Hortacophus n. gen. Also, two additional species for Paracophus are described (P. victoriensis n. sp. and P. velazquezi n. sp.). Diagnoses for all genera and dichotomous keys for genera and species are provided. Finally, the taxonomic relationships between the insular and continental taxa of the tribe are discussed, and the different taxonomic placements they had over time, with some genera located in Phalangopsinae and Luzarinae (Phalangopsidae) and Pentacentrinae (Gryllidae).

Identification of the type locality of the South Island Brown Kiwi Apteryx australis

New Zealand’s iconic, flightless and endangered species of kiwi (Apterygidae) are at risk of extinction on the mainland due to predation by introduced mammals. In order to provide effective conservation management a robust understanding of genetic variation in the group is needed. Recent genomic analyses of kiwi suggest that several cryptic and as yet undescribed lineages occur in the South Island, most notably within a taxon that has until now been called Apteryx australis australis, the South Island Brown Kiwi or Tokoeka. In order for these lineages to be formally described and treated as separate conservation units it is first necessary to determine from which lineage of Tokoeka the holotype was collected. To determine this, we generated a near complete mitochondrial genome and nuclear SNP dataset for the holotype and compared these with living kiwi populations. Our results definitively assign the holotype to the Stewart Island population of brown kiwi which until now was recognized as a distinct subspecies Apteryx australis lawyri (Rothschild, 1893). This leads us to synonymize Apteryx lawryi Rothschild, 1893 within Apteryx australis Shaw, 1813. As the holotype was collected by sealers in the early 19th century, the result also provides a novel insight into the activities of early sealers in New Zealand. New names for taxa will need to be erected for any mainland South Island taxa described, because there are no scientific names available for taxonomy.

Echolocation call frequency variation in horseshoe bats: molecular basis revealed by comparative transcriptomics.

Recently diverged taxa with contrasting phenotypes offer opportunities for unravelling the genetic basis of phenotypic variation in nature. Horseshoe bats are a speciose group that exhibit a derived form of high-duty cycle echolocation in which the inner ear is finely tuned to echoes of the narrowband call frequency. Here, by focusing on three recently diverged subspecies of the intermediate horseshoe bat (Rhinolophus affinis) that display divergent echolocation call frequencies, we aim to identify candidate loci putatively involved in hearing frequency variation. We used de novo transcriptome sequencing of two mainland taxa (himalayanus and macrurus) and one island taxon (hainanus) to compare expression profiles of thousands of genes. By comparing taxa with divergent call frequencies (around 15 kHz difference), we identified 252 differentially expressed genes, of which six have been shown to be involved in hearing or deafness in human/mouse. To obtain further validation of these results, we applied quantitative reverse transcription-PCR to the candidate gene FBXL15 and found a broad association between the level of expression and call frequency across taxa. The genes identified here represent strong candidate loci associated with hearing frequency variation in bats.

Fostering Conservation via an Integrated Use of Conventional Approaches and High-Throughput SPET Genotyping: A Case Study Using the Endangered Canarian Endemics Solanum lidii and S. vespertilio (Solanaceae).

Islands provide unique opportunities to integrated research approaches to study evolution and conservation because boundaries are circumscribed, geological ages are often precise, and many taxa are greatly imperiled. We combined morphological and hybridization studies with high-throughput genotyping platforms to streamline relationships in the endangered monophyletic and highly diverse lineage of Solanum in the Canarian archipelago, where three endemic taxa are currently recognized. Inter-taxa hybridizations were performed, and morphological expression was assessed with a common-garden approach. Using the eggplant Single Primer Enrichment Technology (SPET) platform with 5,093 probes, 74 individuals of three endemic taxa (Solanum lidii, S. vespertilio subsp. vespertilio, and S. vespertilio subsp. doramae) were sampled for SNPs. While morphological and breeding studies showed clear distinctions and some continuous variation, inter-taxon hybrids were fertile and heterotic for vigor traits. SPET genotyping revealed 1,421 high-quality SNPs and supported four, not three, distinct taxonomic entities associated with post-emergence geological, ecological and geographic factors of the islands. Given the lack of barriers to hybridization among all the taxa and their molecular differences, great care must be taken in population management. Conservation strategies must take account of the sexual and breeding systems and genotypic distribution among populations to successfully conserve and restore threatened/endangered island taxa, as exemplified by Solanum on the Canary Islands.

Floral Trait Evolution of Angiosperms on Pacific Islands.

Animals frequently evolve unique suites of traits on islands, but whether plants evolve comparable island syndromes remains unresolved. Here, we test the prediction on the basis of natural history observations that insect-pollinated plants evolve smaller flowers on islands than on mainland communities. We examined 556 plant species representing 136 phylogenetically independent contrasts between island and mainland sister taxa. We focused on endemic taxa originating from the Americas associated with seven tropical and subtropical islands of the Pacific Ocean. Contrary to conventional wisdom, flowers were not on average smaller on islands than on the mainland. On specific archipelagos (the Galápagos Islands and Revillagigedo Islands), however, island taxa did evolve smaller flowers. Divergence in flower size between island and mainland taxa also varied among taxonomic families, such that some plant families evolved smaller flowers on islands, other families evolved larger flowers on islands, and some families exhibited no divergence in flower size between island and mainland taxa. Overall, our results show that there is no general island syndrome for flower size, but instead that the evolution of floral morphology is complex and context dependent, depending on variation among islands and plant families. Our results also suggest that if island floras are typically dominated by small flowered species, as suggested by natural history observations, then ecological filtering is a more likely explanation of this pattern than evolutionary divergence postcolonization. We propose future studies that could disentangle the relative roles of ecological filtering and evolution in the distribution of floral traits on islands.

On the taxonomy and distribution of Varanus salvator andamanensis Deraniyagala, 1944 (Reptilia: Varanidae), including a redescription of the type specimens and a discussion about its allopatric co-occurrence with V. s. macromaculatus on the Nicobar Islands.

We provide a detailed redescription of the two original type specimens of the little-known, endemic Andaman water monitor, Varanus salvator andamanensis Deraniyagala, 1944. Examination of further voucher specimens allows for an expanded morphological diagnosis of this island taxon and comparison with other currently recognized subspecies of the wide-spread Southeast Asian water monitor. Based on the specimens examined, V. s andamanensis is characterized by a homogenous black dorsal background colour, with five to seven, more or less distinctive transverse rows of small spots or ocelli, light yellowish dots arranged sporadically between transverse spot/ocelli rows on the body, light yellowish coloured spots distributed sporadically throughout both forelimbs and hind limbs; 17-18 prominent rows of light spots continuing from base of tail to its tip dorsally with sporadically arranged dots on lateral sides of tail; and higher scale counts in transverse dorsal scale rows. Based on photographic evidence and examination of museum specimens, V. s. andamanensis inhabits both the Andaman and southern Nicobar Islands, which politically belong to the Republic ofIndia. In addition, we confirm the presence of V. s. macromaculatus in the northern and central Nicobar Islands, thus providing evidence for the allopatric co-occurrence of two different water monitor subspecies in these remote archipelagos.

Does Channel Island Acmispon (Fabaceae) form cohesive evolutionary groups?

The California Channel Islands are unique relative to other island chains due to their close proximity to the California mainland and the fact that individual islands, or groups of islands, vary in their distance to the mainland and other islands. This orientation raises questions about whether island taxa with widespread distributions form cohesive evolutionary units, or if they are actually composed of several distinct evolutionary entities, either derived from independent mainland-to-island colonization events or divergence due to prolonged allopatric isolation. The 4 northern islands are clustered in a line (6–8 km separation among islands), while the 4 southern islands are widely spaced (34–45 km separation among islands), which should impact the amount of gene flow and genetic connectivity among islands. We used nuclear microsatellite markers to examine the genetic structure and cohesion of 2 island shrubs, Acmispon dendroideus and A. argophyllus, which are widely distributed across the California Channel Islands. Both focal species contain varieties with multi-island distributions, with A. dendroideus exhibiting a greater distribution on the northern islands and A. argophyllus exhibiting a greater distribution on the southern islands. Substantial genetic divergence was observed for 2 single-island endemic varieties, A. dendroideus var. traskiae and A. agrophyllus var. niveus, confirming that allopatric isolation can lead to genetic divergence. The widespread Acmispon dendroideus var. dendroideus and single-island endemic A. dendroideus var. veatchii formed a cohesive evolutionary group that spans all 4 northern islands and 1 southern island, Santa Catalina, indicating that the northern and southern islands have been genetically linked in the past but do not display evidence of contemporary gene flow. In contrast, widespread A. argophyllus var. argenteus was composed of moderately distinct genetic groups on each of the 4 southern islands, with no evidence of recent gene flow among islands. These results demonstrate that isolation among islands has led to significant divergence among the southern islands, but that the commonly recognized split between northern and southern islands does not impact all taxa equally.

A striking new species of leaf warbler from the Lesser Sundas as uncovered through morphology and genomics

Leaf warblers (Aves; Phylloscopidae) are a diverse clade of insectivorous, canopy-dwelling songbirds widespread across the Old World. The taxonomy of Australasian leaf warblers is particularly complex, with multiple species-level divergences between island taxa in the region requiring further scrutiny. We use a combination of morphology, bioacoustics, and analysis of thousands of genome-wide markers to investigate and describe a new species of Phylloscopus leaf warbler from the island of Rote in the Lesser Sundas, Indonesia. We show that this new Rote Leaf Warbler is morphologically and genomically highly distinct from its congenerics, but do not find vocal differentiation between different island taxa. We discuss the behaviour and ecology of this highly distinctive new species, and make recommendations about its conservation status. We believe this constitutes the first description of a novel bird species that is partly based on insights from massive amounts of genome-wide DNA markers.

Colonization and divergence: phylogeography and population genetics of the Atlantic coast beach mice

Barrier island taxa provide an opportunity to investigate recent evolutionary processes, such as colonization and isolation of recently diverged taxa, and provide important insights into understanding contemporary diversity and the assessment of conservation units. Using rapidly evolving genetic markers (mitochondrial DNA and microsatellites), we studied the Atlantic coast beach mouse subspecies (Peromyscus polionotus decoloratus, P. p. niveiventris, and P. p. phasma). Our data indicate that each of the extant coastal subspecies (P. p. niveiventris and P. p. phasma) is comprised of unique haplotypes indicative of their isolation, while the extinct subspecies, P. p. decoloratus, contain a single haplotype, which was shared with P. p. phasma. Moreover, all the coastal haplotypes originate from a single mainland haplotype found in central Florida, USA. The microsatellite data indicated high levels of genetic structure among our sampled populations. Additionally, these data group the populations into three distinct genetic clusters, with each of the extant coastal subspecies belonging to their own cluster and the mainland individuals forming a separate cluster. The extant Atlantic coast beach mice are on separate evolutionary trajectories, thus representative of separate taxonomic units. Therefore, the data support that two extant subspecies on the Florida Atlantic coast fit the Distinct Population Segment designation and should be managed and conserved as two separate independent units.

Island biodiversity conservation needs palaeoecology.

The discovery and colonization of islands by humans has invariably resulted in their widespread ecological transformation. The small and isolated populations of many island taxa, and their evolution in the absence of humans and their introduced taxa, mean that they are particularly vulnerable to human activities. Consequently, even the most degraded islands are a focus for restoration, eradication, and monitoring programmes to protect the remaining endemic and/or relict populations. Here, we build a framework that incorporates an assessment of the degree of change from multiple baseline reference periods using long-term ecological data. The use of multiple reference points may provide information on both the variability of natural systems and responses to successive waves of cultural transformation of island ecosystems, involving, for example, the alteration of fire and grazing regimes and the introduction of non-native species. We provide exemplification of how such approaches can provide valuable information for biodiversity conservation managers of island ecosystems.

Orangutans, enamel defects, and developmental health: A comparison of Borneo and Sumatra.

Orangutans (Pongo sp.) show among the highest occurrence of three types of developmental enamel defect. Two are attributed to nutritional factors that reduce bone growth in the infant's face early in development. Their timing and prevalence indicate that Sumatra provides a better habitat than does Borneo. The third type, repetitive linear enamel hypoplasia (rLEH) is very common but its etiology is not understood. Our objective is to draw attention to this enigmatic, episodic stressor in the lives of orangutans. We are concerned that neglect of this possible marker of ill health may be contributing, through inaction, to their alarming decline in numbers. Width and depth of an LEH are considered proxies for duration and intensity of stress. The hypothesis that Bornean orangutans would exhibit relatively wider and deeper LEH was tested on 163 independent episodes of LEH from 9 Sumatran and 26 Bornean orangutans measured with a NanoFocus AG "µsurf Mobile Plus" scanner. Non-normally distributed data (depths) were converted to natural logs. No difference was found in width of LEH among the two island taxa; nor are their differences in width or depth between the sexes. After controlling for significant differences in LEH depths between incisors and canines, defects are, contrary to prediction, significantly deeper in Sumatran than Bornean animals (median = 28, 18 µm, respectively). It is concluded that repetitive LEH records an unknown but significant stressor present in both Sumatra and Borneo, with an average periodicity of 6 months (or multiples thereof) that lasts about 6-8 weeks. It is worse in Sumatra. Given this patterning, shared with apes from a wide range of ecological and temporal sources, rLEH is more likely attributable to disease than to malnutrition.

Influences of oceanic islands and the Pleistocene on the biogeography and evolution of two groups of Australasian parrots (Aves: Psittaciformes: Eclectus roratus, Trichoglossus haematodus complex). Rapid evolution and implications for taxonomy and conservation

AbstractThe Australasian region is a centre of biodiversity and endemism, mainly based on the tropical climate in combination with the large amount of islands. During the Pleistocene, islands of the Sahul Shelf (Australia, New Guinea, Aru Islands) had been part of the same land mass, while islands within the Wallacea (Lesser Sunda Islands, Moluccas, Sulawesi etc.) remained isolated. We investigated biogeographical avian diversification patterns of two species complexes across the Wallacea and the Sahul Shelf: the Eclectus Parrot Eclectus roratus Wagler, 1832, and the Rainbow Lorikeet Trichoglossus haematodus Linnaeus, 1771. Both species are represented by a large number of described geographical subspecies. We used mitochondrial cytochrome b (cyt b) sequences for phylogenetic and network analysis to detect biogeographic roles of islands and avian diversification patterns. The number of threatened taxa in this region is increasing rapidly and there is an urgent need for (sub-)species conservation in this region. Our study provides first genetic evidence for treating several island taxa as distinct species. In both species complexes similar genetic patterns were detected. Genetic diversification was higher across the islands of the Wallacea than across the islands of the Sahul Shelf. Divergence in E. roratus can be dated back about 1.38 million years ago, whereas in the younger T. haematodus it was 0.80 million years ago. Long distance dispersal was the most likely event for distribution patterns across the Wallacea and Sahul Shelf. The geographic origin of the species-complex Eclectus roratus spp. is supposed to be Wallacean, but for the species-complex Trichoglossus haematodus spp. it is supposed to be non-Wallacean. Trichoglossus euteles, so far considered a distinct species, clearly belongs to the Trichoglossus-haematodus-complex. The only case of sympatry in the complex is the distribution of T. (h.) euteles and T. h. capistratus on Timor, which means a rapid evolution from one ancestor into two distinct species within only 800,000 years. For all other taxa a Checkerboard distribution pattern is present. In this complex, 8 taxa are already treated as separate species (del Hoyo et al. 2014). Based on genetic evidence, the following populations are supported to represent phylogenetic units: (1) N New Guinea (haematodus) incl. Biak (rosenbergii), Bismarck Archipelago (massena), and New Caledonia (deplanchii); (2) Flores (weberi); (3) E Australia (moluccanus) incl. Aru Islands (nigrogularis) and S New Guinea (caeruleiceps); (4) N Australia (rubritorquis); (5) Timor 1st lineage (capistratus) incl. Sumba (fortis); (6) Bali and Lombok (mitchellii); (7) Sumbawa (forsteni); (8) Timor 2nd lineage (euteles). Those 8 phylogenetic units are not identical to the 8 species listed by del Hoyo et al. (2014). Several populations on smaller islands are under decline, a separate species status may lead to a higher conservation status in both species complexes, which are currently listed as “Least Concern”. Eclectus roratus is currently treated as monospecific. Based on genetic evidence, the following populations are suggested being treated as valid species: (1) Sumba (Eclectus cornelia), (2) Tanimbar Islands (E. riedeli), (3) Moluccas (E. roratus), and (4) New Guinea (E. polychloros incl. Aru Islands (E. aruensis), and Solomon Island (E. solomonensis).

A REMARKABLE FEATURE OF BIODIVERSITY OF THE COASTAL, MARINE AND ISLAND ECOSYSTEMS OF THE CASPIAN SEA. A NEW LOOK AT THE AGE OF ISLANDS AND LEVEL MODE

Aim. During the 2009-13 period of time joint efforts of eco-eographical faculty of Dagestan State University and the Institute of Applied Ecology of the Republic of Dagestan made large-scale comprehensive studies of flora and fauna of coastal and island ecosystems of the Middle Caspian. The program of the expedition involves the establishment of species diversity of animal and plant life of the population of the study area. The main purpose of this article is to establish the reasons for the high proportion of the indigenous component of the aquatic biota and causal interpretation discovered during research expeditions of the endemism among taxa of an island fauna and flora. Methods. Expedition research covered the western and eastern coast of the Middle Caspian, and the major islands (Chechen Island, Tyleniy, Nordova, Kulaly) of this part of the sea. In faunal studies traditional methods, such as hand-picking, mowing, light traps with quartzemitters, ground traps were used. A new version of the field collecting entomological material was tested: Barber trapsin combination with LED lamps. The last only switched on at night. Location of traps recorded by GPS-navigator. Traps Barbera functioned throughout the expedition period. Removal of the collected material was performed at intervals of 3 days. The need for a causal interpretation of the contemporary configuration of habitat in the species composition of the biota of the study area, has led us to develop a hydrodynamic GIS model of the Middle and North of the Caspian sea. To solve this problem prepared three-dimensional model of the bottom of the Middle and North of the Caspian sea in GIS "Map 2011". The base level of the Caspian sea in this simulation adopted the mark -28 m Matrix, ensuring the functioning of the hydrodynamic GIS model based on approximately twenty thousand marks depths. Results. According to the results of pre-processing of field data set, the General picture of the floristic (higher plants) and fauna (some groups of invertebrates) species diversity (table. 1). It should be emphasized that the biota of the Islands of the Middle Caspian, in General, consists of taxa widely distributed in the Eastern and, to a lesser extent, the Western coast. There are also species the area which goes far beyond the region of the Caspian sea. However, in table 1 preliminary faunal and floral evidence suggests that in the modern biota of the Islands of the Caspian sea found also new to science species, at present unknown in the continental part of the Caspian sea. It taxa species or subspecies rank. That said, modern faunistic or floristic status of this group of species should be considered endemic. Main conclusions . Kind of part of the Caspian autochthonous fauna is largely because of its complex origins. A catastrophic reduction in the area of water surface of the sea takes place with a gradual decrease of its level before -39 m Middle Caspian, since the level of -39 m and -50 m retains approximately the same configuration of the water surface. The decline -100 m and even up to -150 m not accompanied by a catastrophic decline in water surface area of the Middle Caspian sea. Therefore, it should be recognized that the conservation and co-evolutionary development of the unique fauna of the Caspian sea, an important buffer role played by the Middle Caspian. Thus, a causal interpretation of the autochthonous trends and, as a consequence, a high level of endemism taxa of aquatic biota is not straightforward. A different situation with understanding and explanation of the pattern of endemism coastal and especially island taxa. Modern faunistic or floristic status of the new species should be considered endemic. In this group of species identified taxa of species and subspecies rank. The formation and evolutionary stabilization of these taxa requires a time sufficient to cause diagnostically significant features. And this is possible only with the existence in the waters of the Middle and North of the Caspian sea island sushi throughout the Holocene (even during periods of high sea level). Of course that modern configuration of habitat taxa island biota of the Middle Caspian sea due to the magnitude and time duration of transgressive-regressive cycles of the sea and the reasons that determine the direction of these events. In accordance with the nature of these cycles has been a change in the species composition and structural organization of coastal and island communities.

Patterns of genetic diversity in Phoenix canariensis, a widespread oceanic palm (species) endemic from the Canarian archipelago

Understanding how genetic diversity is structured on oceanic island taxa requires the integration of physical, biological and anthropomorphic factors. Founder effects coupled with limited dispersal over sea barriers typically result in low levels of genetic variation in island populations. In widespread species, restriction in gene flow across large areas leads to patterns of isolation by distance (IBD), but recent population-based studies indicate that genetic structure on islands can be complex even at local scales. Here, we investigated the patterns of genetic variation in a widespread island palm (Phoenix canariensis) displaying reproductive syndromes associated with extensive dispersal (wind pollination and zoochory). Genetic variation was assessed at eight nuclear microsatellite loci in 330 individuals of 15 Canarian populations. Our results showed that levels of within-population genetic diversity in P. canariensis depend on the island considered, with a strong decreasing pattern from the easternmost and oldest island to the westernmost and youngest islands. A Mantel test supported a stepping-stone model of differentiation across the archipelago that fits the sequence of island emergence, and results from ABC and clustering analyses also corresponded with this progression rule. In addition, our analyses were congruent with the idea that the only large population found on Lanzarote has an anthropogenic origin. Despite the high dispersal potential of P. canariensis, our analyses suggest that the geographical configuration of the Canary Islands and a relatively recent pattern of differentiation across islands appear to have had a primary influence on the genetic structure of this island taxon.