Hawaiian Species Research Articles

The genusLobariella(Ascomycota:Lobariaceae) in Hawaii: late colonization, high inferred endemism and three new species resulting from “micro-radiation”

AbstractWe assessed the taxonomy and phylogenetic relationships of Hawaiian species of the neotropical genusLobariella. A single species was previously reported from the archipelago, the widespread neotropicalL. crenulata. We targeted three loci of the mitochondrial and nuclear ribosomal rDNA gene cistron (mtSSU, nuLSU, ITS) and also performed a molecular clock analysis. Our results show thatL. crenulatas. str. is seemingly present in the archipelago based on older herbarium collections. However, HawaiianLobariellaincludes three additional, presumably endemic, species unrelated toL. crenulataand new to science:L. flynnianaLücking, Moncada & C. W. Sm., with richly branched marginal phyllidia giving the thallus a fruticose appearance;L. robustaLücking, Moncada & C. W. Sm., with a rather thick thallus and abundant, large, laminal phyllidia; andL. sandwicensisLücking, Moncada & C. W. Sm., with a delicate thallus producing apothecia.Lobariella flynnianarepresents a novel morphotype within the genus, thus far known only from Hawaii. All three species are very closely related, forming a well-supported, monophyletic clade in spite of their morphological differences, suggesting local micro-radiation. Molecular clock analysis indicates that this clade colonized the islands between 1–8 mya and diverged between 0–2 mya. We interpret recent colonization as one of the main reasons why this clade has not diversified further.

The false click beetles (Coleoptera: Eucnemidae) of Hawai'i

The Hawaiian eucnemid fauna is reviewed. Each of the known species is redescribed along with descriptions of 20 new species. An overview of the distribution as well as any known aspects of natural history are provided for each species, and keys to identify the Hawaiian species are provided. The following 20 new taxa are described: Fornax muonai new species (type locality Hawai'i), Fornax swezeyi new species (Maui), Fornax yoshimotoi new species (Kaua'i), Dromaeolus acaciakoa new species (Kaua'i), Dromaeolus breviangularis new species (Kaua'i), Dromaeolus forbesi new species (Kaua'i), Dromaeolus halehakuensis new species (Maui), Dromaeolus hardyi new species (Maui), Dromaeolus harryi new species (Kaua'i), Dromaeolus kokeensis new species (Kaua'i) Dromaeolus leroyi new species (Kaua'i), Dromaeolus nualoloensis new species (Kaua'i), Dromaeolus oahuensis new species (O'ahu), Dromaeolus paulayi new species (Kaua'i), Dromaeolus ruffini new species (Hawai'i), Dromaeolus sandrae new species (Maui), Dromaeolus susanae new species (Kaua'i), Dromaeolus waikapuensis new species (Maui), Dromaeolus youngi new species (Kaua'i) and Dromaeolus zimmermani new species (Kaua'i). Dromaeolus pachyderes var. kauaiensis Sharp is elevated to D. kauaiensis Sharp, new status. Each species is illustrated with a dorsal habitus image and accompanied by a distribution map.

Two new endemic cave-living moths from Hawai‘i Island: a new species of <br />Pseudoschrankia (Erebidae), and a new species of Mestolobes Crambidae)

Two new endemic Hawaiian Lepidoptera species are herein described; both are associated with caves. The new species, Pseudoschrankia nohoana sp. nov. and Mestolobes olali sp. nov., have been found exclusively in caves or cave entrances on the Big Island of Hawai‘i, although neither species appears to possess any specializations for living in caves.

Movements of four native Hawaiian birds across a naturally fragmented landscape

Animals often increase their fitness by moving across space in response to temporal variation in habitat quality and resource availability, and as a result of intra and inter‐specific interactions. The long‐term persistence of populations and even whole species depends on the collective patterns of individual movements, yet animal movements have been poorly studied at the landscape level. We quantified movement behavior within four native species of Hawaiian forest birds in a complex lava‐fragmented landscape: Hawai‛i ‘amakihi Chlorodrepanis virens, ‘oma‘o Myadestes obscurus, ‘apapane Himatione sanguinea, and ‘i‘iwi Drepanis coccinea. We evaluated the relative importance of six potential intrinsic and extrinsic drivers of movement behavior and patch fidelity: 1) forest fragment size, 2) the presence or absence of invasive rats (Rattus sp.), 3) season, 4) species, 5) age, and 6) sex. The study was conducted across a landscape of 34 forest fragments varying in size from 0.07 to 12.37 ha, of which 16 had rats removed using a treatment‐control design. We found the largest movements in the nectivorous ‘apapane and ‘i‘iwi, intermediate levels in the generalist Hawai‛i ‘amakihi, and shortest average movement for the ‘oma‘o, a frugivore. We found evidence for larger patch sizes increasing patch fidelity only in the ‘oma‘o, and an effect of rat‐removal increasing patch fidelity of Hawai‛i ‘amakihi only after two years of rat‐removal. Greater movement during the non‐breeding season was observed in all species, and season was an important factor in explaining higher patch fidelity in the breeding season for ‘apapane and ‘i‘iwi. Sex was important in explaining patch fidelity in ‘oma‘o only, with males showing higher patch fidelity. Our results provide new insights into how these native Hawaiian species will respond to a changing environment, including habitat fragmentation and changing distribution of threats from climate change.

Type Specimens of Hawaiian Land Snails in the Smithsonian Institution, National Museum of Natural History, with Lectotype Designations

Pacific island land snail faunas are among the most threatened faunas in the world, having suffered a higher rate of extinction than any other major animal group. The Hawaiian land snails are among the most species-rich and most severely effected of these faunas, yet the current status of most of the Hawaiian species is unknown. Most of the major taxonomic studies on the fauna were undertaken 50–100 years ago and only certain groups were comprehensively studied. New research is uncovering undescribed species, both extant and extinct. The need for rigorous taxonomic treatment of the group is acute if the taxonomic and conservation status of the many species is to be ascertained, and the basis for such research is comprehensive study of type material. The Smithsonian's National Museum of Natural History holds type material of 39 nominal species-group taxa of Hawaiian land snails belonging to eight families; this annotated catalog provides details of this material. Of these taxa, 29 were described by Augustus Addison Gould from material collected by the U.S. Exploring Expedition of 1838–1842. For completeness, we also provide details for one lot of purported paralectotypes that are here inferred not to have been syntypes and one lot representing an unavailable infrasubspecific name. We designate lectotypes for 12 species-group taxa . Yeung, Norine W., Robert H. Cowie, Kenneth A. Hayes, and Ellen E. Strong. Type Specimens of Hawaiian Land Snails in the Smithsonian Institution, National Museum of Natural History, with Lectotype Designations. Smithsonian Contributions to Zoology, number 647 , vi + 34 pages, 11 figures, 2017.

Into Africa: Molecular phylogenetics and historical biogeography of sub-Saharan African woodferns (Dryopteris).

Our goal was to infer the phylogenetic relationships and historical biogeography of the genus Dryopteris with a focus on taxa in sub-Saharan Africa and neighboring islands. In general, little is known about the relationships between African fern species and their congeners in other geographic regions, and our aim was to determine whether the sub-Saharan African species of Dryopteris are monophyletic and evolved within Africa or arrived there via repeated dispersals into Africa from other regions. We obtained sequence data for five chloroplast markers from 214 species of Dryopteris and 18 outgroups. We performed phylogenetic and molecular dating analyses using a Bayesian relaxed clock method in BEAST with fossil and secondary calibration points and estimated ancestral ranges for the genus globally by comparing multiple models in BioGeoBEARS. We found that 22 of 27 accessions of sub-Saharan African Dryopteris belong to a large clade of 31 accessions that also includes taxa from Indian and Atlantic Ocean islands. Additional accessions of taxa from our regions of interest have Asian, Hawaiian, European, or North American species as their closest relatives. The majority of sub-Saharan African Dryopteris species are descended from a shared common ancestor that dispersed to Africa from Asia approximately 10 Ma. There have been subsequent dispersal events from the African mainland to islands in the Atlantic and Indian Oceans, including Madagascar. Several additional species are estimated to have descended from ancestors that reached Africa via separate events over the last roughly 20 million years.

The intersection of basic research and conservation: a 30-year study of the Critically Endangered Schiedea adamantis (Caryophyllaceae) on Lē‘ahi (Diamond Head Crater), Hawai‘i

AbstractWe report on how a long-term study of the reproductive biology of the Critically Endangered Schiedea adamantis (Caryophyllaceae), one of Hawai‘i's rarest plant species, was leveraged for conservation purposes. Our major goals were to provide seeds with the greatest genetic variation possible for reintroduction and to ensure that both female and hermaphroditic plants of this wind-pollinated species were reintroduced in a manner that maximized both outcrossing and seed production. Schiedea adamantis was one of the first Hawaiian plant species listed under the Endangered Species Act (USA). The species has been studied intensively to test hypotheses addressing the evolution of breeding systems. Information on outcrossing levels and the extent of inbreeding depression was integrated into ongoing reintroduction efforts. Population size peaked in 1994, when 267 flowering individuals were found on Lē‘ahi (Diamond Head Crater). By 2016 only 17 flowering individuals were present, with drought and invasive species being possible causes of this decline. Reintroduction attempts in 1998 using genetically diverse seeds were unsuccessful because of drought and a lack of sufficient supplemental irrigation. Additional reintroduction attempts in 2012 and 2014 were more successful because of increased supplemental irrigation. Plants used in reintroductions represent genotypes long since absent in the natural population, and may contain the genetic variability essential for evolutionary responses to climate change and the spread of invasive species. The destruction of many plants reintroduced in 2015 and 2016 by a fire in March 2016 highlights the need for additional restoration areas at Lē‘ahi and elsewhere, and storage of seeds for future use.

The carbon and nitrogen ecophysiologies of two endemic tropical orchids mirrors those of their temperate relatives and the local environment.

Orchids are one of the most widely distributed plant families. However, current research on the ecophysiology of terrestrial orchids is biased towards temperate species. Thus, it is currently unknown whether tropical terrestrial orchids belong to similar trophic guilds as their temperate relatives. To examine the ecophysiologies of two tropical terrestrial orchids, I analysed the carbon and nitrogen stable isotope compositions and nitrogen concentrations of the Hawaiian endemics Anoectochilus sandvicensis and Liparis hawaiensis. I compared these values with those of surrounding vegetation and their temperate relatives. I found that A. sandvicensis was consistently enriched in the heavy isotope of nitrogen (15N) and had higher nitrogen (N) concentrations than surrounding vegetation, and these values were even higher than those of its temperate relatives. Carbon stable isotope composition among populations of A. sandvicensis varied by island. These results point to local environment and evolutionary history determining the ecophysiology of this species. Whereas L.hawaiensis was also enriched in 15N and had on average higher N concentrations than surrounding vegetation, these values were not significantly different from temperate relatives, indicating that evolutionary history may be a stronger predictor of this orchid species' ecophysiology than environment. I suggest that both Hawaiian species are potentially partially mycoheterotrophic.

Mycorrhizal colonization is compatible with exponential fertilization to improve tree seedling quality

ABSTRACTThis study tested the ability of exponential fertilization to minimize the tradeoff of increased seedling size and nutrient concentration with good root colonization by mycorrhizae. Two native Hawaiian tree species were tested. Four rates of nitrogen (N) (0–3 g per seedling) were delivered by the method of exponential fertilization to seedlings with and without inoculation with a native strain of arbuscular mycorrhizal fungus. For both species, the highest growth and nutrient concentrations occurred with mycorrhizal colonization at 1–2 g N per seedling. Growth of inoculated seedlings was significantly lower at 3.0 g N per seedling, likely due to a large reduction in mycorrhizal colonization. Our results demonstrate that mycorrhizal colonization is not only compatible with exponential fertilization, combined they produce larger seedlings with higher nutrient content. This should improve outplanting success in degraded or challenging sites.

Spatial Scale, Genetic Structure, and Speciation of Hawaiian Endemic Yeasts 1

Two Hawaiian endemic yeast species, Metschnikowia hawaiiensis and Metschnikowia hamakuensis , were examined by means of multilocus characterization. In spite of their narrow range of distribution, restricted to the island of Hawai‘i, both species were found to be polymorphic at several loci. Alleles of different loci were distributed independently within local populations, confirming that sexual reproduction prevails among these facultatively asexual organisms. No alleles were shared across species, confirming their reproductive isolation. Although the sample size for the northern species, M. hamakuensis , is much less ( N = 7) than that for its southern relative, M. hawaiiensis ( N = 161), their genetic diversity is comparable. Genetic differentiation was detected in M. hawaiiensis populations at both regional (ca. 30–40 km) and local (ca. 1 km) scales. A single isolate recovered in a separate locality exhibited considerable allelic divergence from others, indicating that genetic isolation can occur over relatively short distances and suggesting a first step towards cessation of gene flow, which is required for speciation.

What to do when we can't bank on seeds: What botanic gardens can learn from the zoo community about conserving plants in living collections

What to do when we can't bank on seeds: What botanic gardens can learn from the zoo community about conserving plants in living collections

Patterns of Floral Visitation to Native Hawaiian Plants in Presence and Absence of Invasive Argentine Ants

Abstract: Invasive ants can influence abundance and diversity of insect pollinators, and this effect may be expected to be especially strong on oceanic islands. We examined abundance of native Hylaeus bees and patterns of flower visitation to three native Hawaiian plant species (Leptecophylla tameiameiae, Santalum haleakalae, and Geranium cuneatum) in presence and absence of invasive Argentine ants (Linepithema humile) in the subalpine shrubland of Haleakalā volcano. Native bees, nonnative honeybees, and microlepidoptera were responsible for the majority of visits to flowers of the three plant species. Ants visited flowers of S. haleakalae and G. cuneatum relatively commonly in ant-invaded zones but were less common or absent on flowers of L. tameiameiae in the same zones. Zones with ants had fewer Hylaeus bees in yellow pan traps than the zone without ants, and overall flower visitation rates to one plant species, G. cuneatum, were six times lower in sites containing ants. In one of two observation years...

Annotated catalogue of types of Hawaiian land and freshwater snails (Mollusca: Gastropoda) in the Muséum national d'Histoire naturelle, Paris, with lectotype designations

ABSTRACT Pacific island land snail faunas are among the most threatened faunas in the world, having suffered a higher rate of extinction than any other major animal group. The Hawaiian land snails are among the most species rich and most severely impacted of these faunas, yet the current status of most of the Hawaiian species is unknown. Most of the major taxonomic studies on the fauna were under-taken 50–100 years ago and only certain groups were comprehensively revised. New research is uncovering undescribed species, both extant and extinct. The need for rigorous taxonomic treatment of the group is acute if the validity and conservation status of the many species is to be ascertained, and the basis for such research is comprehensive study of type material. The Museum national d'Histoire naturelle, Paris, holds type material of 38 nominal species-group taxa of Hawaiian land and freshwater snails belonging to six families, overwhelmingly the Achatinellidae Gulick, 1873 and Amastridae Pilsbry, 1910; this a...

Linking dominant Hawaiian tree species to understory development in recovering pastures via impacts on soils and litter

AbstractLarge areas of tropical forest have been cleared and planted with exotic grass species for use as cattle pasture. These often remain persistent grasslands after grazer removal, which is problematic for restoring native forest communities. It is often hoped that remnant and/or planted trees can jump‐start forest succession; however, there is little mechanistic information on how different canopy species affect community trajectories. To investigate this, I surveyed understory communities, exotic grass biomass, standing litter pools, and soil properties under two dominant canopy trees—Metrosideros polymorpha (‘ōhi‘a) and Acacia koa (koa)—in recovering Hawaiian forests. I then used structural equation models (SEMs) to elucidate direct and indirect effects of trees on native understory. Native understory communities developed under ‘ōhi‘a, which had larger standing litter pools, lower soil nitrogen, and lower exotic grass biomass than koa. This pattern was variable, potentially due to historical site differences and/or distance to intact forest. Koa, in contrast, showed little understory development. Instead, data suggest that increased soil nitrogen under koa leads to high grass biomass that stalls native recruitment. SEMs suggested that indirect effects of trees via litter and soils were as or more important than direct effects for determining native cover. It is suggested that diverse plantings which incorporate species that have high carbon to nitrogen ratios may help ameliorate the negative indirect effects of koa on natural understory regeneration.

Trait convergence and diversification arising from a complex evolutionary history in Hawaiian species of Scaevola.

Species variation in functional traits may reflect diversification relating to convergence and/or divergence depending on environmental pressures and phylogenetic history. We tested trait-environment relationships and their basis in finer-scale evolutionary processes among nine extant Hawaiian species of Scaevola L. (Goodeniaceae), a taxon with a complex history of three independent colonizations by different phylogenetic lineages, parallel ecological specialization, and homoploid hybridization events in Hawai'i. Using a wild population for each species, we evaluated traits related to plant function (morphology, leaf and wood anatomy, nutrient and carbon isotope composition). Hawaiian Scaevola species were distributed across coastal, dry forest and wet forest environments; multivariate environmental analysis using abiotic and biotic factors further showed that species from distantly related lineages inhabited similar environments. Many traits correlated with environment (based on the multivariate environmental analysis), considering both distantly related species and more closely related species. Scaevola species within shared habitats generally showed trait convergence across distantly related lineages, particularly among wet forest species. Furthermore, trait diversification through divergence was extensive among closely related Scaevola species that radiated into novel environments, especially in plant morphology and traits affecting water relations. Homoploid hybrid-origin species were "intermediate" compared to their ancestral parent species, and possessed trait combinations relevant for their current habitat. The diversity in functional traits reflected strong influences of both ecology and evolutionary history in native Hawaiian Scaevola species, and trait correspondence with environment was due to the combination of multiple processes within the taxon: trait pre-adaptation and filtering, evolutionary convergence, divergence, and hybridization.

A review of PolynesianCarposina Herrich-Schäffer (Lepidoptera: Carposinidae), with descriptions of four new species

Hawaiian Carposina represent over 17% of the known world fauna of Carposinidae. In contrast, only two species are known for all of French Polynesia in the South Pacific. Here we describe four new species: two from the Hawaiian Islands, Carposina urbanae sp. nov. and C. gagneorum sp. nov., and two from the Society Islands, C. longignathosa sp. nov. and C. brevinotata sp. nov. We further recognize another new Hawaiian species too worn to describe. Additionally, we present the first phylogeny for Polynesian Carposina, including 19 taxa, using one mitochondrial and two nuclear gene regions. The Hawaiian Carposina sampled thus far form a monophyletic clade. Lastly, we provide a framework to better understand the diversification and phylogeography of this group, and provide a summary of currently known host plant associations. Diversification appears to have resulted from interplay between host switching and geographic isolation across the Hawaiian Archipelago.

Taxonomic remarks on the genus Ctenodrilus (Annelida: Cirratulidae) including description of a new species from the Pacific Ocean.

A new species of Ctenodrilus is described based on morphology, anatomy and molecular (COI and 16S) data. Phylogenetic analyses revealed that the newly described Hawaiian species is the sister taxon of the widely distributed C. serratus. Comparisons of K2P distances show distances of at least 10.9 % for 16S and 18.7 % for CO1. Morphology of C. serratus differs from C. pacificus sp. nov. in the shape, number and distribution of multidentate hooks along the body, extent in segments of anterior ventral cilia, and presence of stomach cilia. Ctenodrilus pacificus sp. nov. resembles C. parvulus in terms of the internal anatomy but differs in respect to the shape of multidentate hooks. Asexual reproduction in the new species is described including associated changes in the external morphology and internal anatomy. A revision of the taxonomic characters of Ctenodrilus is also presented in order to provide background information for a better assessment of the widely distributed taxon Ctenodrilus serratus.

Low tolerance to simulated herbivory in Hawaiian seedlings despite induced changes in photosynthesis and biomass allocation.

Seedling herbivory is an important factor underlying plant community diversity and structure. While considerable research has characterized seedling defence in terms of resistance, very little is known about seedling tolerance of herbivory. Moreover, few studies have attempted to identify mechanisms of tolerance across a range of plant species. Seedling tolerance of simulated herbivory was tested in a diverse pool of ten Hawaiian plant species, including several lobeliad species (family Campanulaceae), a grass, a herb and common woody trees and shrubs. Tolerance was measured as the relative survival and growth of damaged plants receiving 50% defoliation with simultaneous jasmonic acid application compared with undamaged control plants, assessed 1·5 and 5weeks after damage. Putative mechanisms of tolerance were measured, including photosynthetic parameters, light use efficiency, and biomass allocation reflecting growth priorities, and analysed using species-level regression analyses on tolerance indices. No species fully tolerated 50% defoliation at either harvest date, and simulated herbivory significantly reduced shoot as well as root biomass. Lobeliad species had particularly low tolerance. Species varied considerably in size, biomass allocation parameters and their constitutive (pre-damage) and induced (post-damage) photosynthetic parameters. However, only constitutive levels of non-photochemical quenching were significantly related to tolerance, indicating that species with more efficient light use (and less heat dissipation) are better at tolerating damage than species with high levels of heat dissipation. Native Hawaiian plants expressed low tolerance to a conservative level of simulated herbivory. Root growth decreased in response to damage, but this was not associated with greater tolerance, suggesting this response may be due to allocation constraints following defoliation and not due to adaptive plasticity. Conservation of native island plants threatened by invasive herbivores should prioritize protection for seedlings for improved regeneration and the persistence of native plants in disturbed habitats.

East Asian Lobelioideae and ancient divergence of a giant rosette Lobelia in Himalayan Bhutan

AbstractLobelioideae comprise about 1200 species in 30 genera worldwide and include famous cases of parallel evolution in the “giant rosette” lobelias occurring in East Africa, Hawaii, and Bhutan. To date, no phylogeny has included the Himalayan giant lobelia, and its age and phylogenetic distance from the Hawaiian and African giant species (the latter in the same section as the Bhutan species) are therefore unknown. Asian Lobelioideae in general have received little attention, partly because of the difficult access to material. Here we use nuclear and plastid markers of Lobelioideae (with worldwide sampling) to test the monophyly of the section that includes most Asian lobelias, and we then use a reduced concatenated matrix to resolve the position of Lobelia nubigena from Bhutan and of the likewise cold‐adapted lowland species L. sessilifolia. Most sequences come from herbarium material. Lobelia nubigena diverged from its Asian lowland relatives 13.8 (12.6–15) million years ago (about the time of the Bhutan Himalaya orogeny), and in an unexpected twist, L. sessilifolia is the sister species to a huge clade (ca. 265 species) that comprises African, South American, Asian, and the entire Hawaiian Lobelioideae radiation. The African and Hawaiian high‐elevation lobelias in our sample are younger than L. nubigena, although the time when gigantism evolved in this species cannot be precisely inferred. Our results support the previously hypothesized Asian origin of (1) the Hawaiian Lobelioideae, (2) Southeast Asian islands lobelias, and (3) the African Lobelia‐Rynchopetalum group, which also reached South America.

The quest to resolve recent radiations: Plastid phylogenomics of extinct and endangered Hawaiian endemic mints (Lamiaceae)

The Hawaiian mints (Lamiaceae), one of the largest endemic plant lineages in the archipelago, provide an excellent system to study rapid diversification of a lineage with a remote, likely paleohybrid origin. Since their divergence from New World mints 4–5 million years ago the members of this lineage have diversified greatly and represent a remarkable array of vegetative and reproductive phenotypes. Today many members of this group are endangered or already extinct, and molecular phylogenetic work relies largely on herbarium samples collected during the last century. So far a gene-by-gene approach has been utilized, but the recent radiation of the Hawaiian mints has resulted in minimal sequence divergence and hence poor phylogenetic resolution. In our quest to trace the reticulate evolutionary history of the lineage, a resolved maternal phylogeny is necessary. We applied a high-throughput approach to sequence 12 complete or nearly complete plastid genomes from multiple Hawaiian mint species and relatives, including extinct and rare taxa. We also targeted 108 hypervariable regions from throughout the chloroplast genomes in nearly all of the remaining Hawaiian species, and relatives, using a next-generation amplicon sequencing approach. This procedure generated ∼20Kb of sequence data for each taxon and considerably increased the total number of variable sites over previous analyses. Our results demonstrate the potential of high-throughput sequencing of historic material for evolutionary studies in rapidly evolving lineages. Our study, however, also highlights the challenges of resolving relationships within recent radiations even at the genomic level.