High levels of male diploidy but low levels of genetic structure characterize <Emphasis Type="Italic">Bombus vosnesenskii</Emphasis> populations across the Western US

Patterns of genetic structure for some bee species suggest that gene flow may be limited across natural and human-created barriers and that local dispersal or natal site fidelity may be common. Interestingly, this past work has primarily focused on female bees, despite the fact that males may differ substantially in their dispersal processes. By examining genetic structure and diploidy in males, it is possible to gain insight into potential barriers to gene flow and drivers of inbreeding. In this study, we examine diploidy as well as regional and local spatial genetic structure using males of Bombus vosnesenskii, a stable bumble bee species found across western North America. Specifically, we investigate patterns of genetic structure in both island and mainland populations, across spatial scales, and over a range of natural and human-altered habitats. We document high levels of male diploidy, with significantly higher levels in mainland populations compared to island populations and increasing diploidy in areas with poor nesting habitat. Interestingly, we also find evidence of significant spatial genetic structure from 0 to 10 km and 0 to 5 km on island and mainland populations, respectively. Finally, we document low but significant genetic differentiation across the region (Φ_ST = 0.049). Overall, this work reveals the unique potential for biogeographic context and local habitat composition to drive male diploidy patterns in bumble bees.     

Higher immunocompetence is associated with higher genetic diversity in feral honey bee colonies (<Emphasis Type="Italic">Apis mellifera</Emphasis>)

Honey bees are the most important managed pollinators as they provide key ecosystem services for crop production worldwide. Recent losses of honey bee colonies in North America and Europe have demonstrated a need to develop strategies to improve their health and conserve their populations. Previously, we showed that feral honey bees—colonies that live in the wild without human assistance—exhibit higher levels of immunocompetence than managed colonies in North Carolina (USA). In a first attempt to investigate the underlying mechanisms of this difference in immune response, here we characterize the genetic composition of feral and managed honey bees using microsatellite markers. Our results reveal significant but small genetic differentiation between feral and managed honey bee colonies (?_CT = 0.047, P?=?0.03) indicating admixture between these two groups. Higher genetic diversity was correlated with higher immune response in feral (P _MANOVA = 0.011) but not managed bees, despite the fact that the latter group showed significantly higher average genetic diversity (P _ANCOVA < 0.001). These findings suggest that genetic diversity is positively associated with immunocompetence in feral honey bee colonies, and that the benefits of genetic diversity are obscured in managed bees, perhaps as a result of artificial selection. We hypothesize that high genetic variability provides the raw material upon which natural selection acts and generates adaptive genotypes in unmanaged populations. Feral populations could be useful sources of genetic variation to use in breeding programs that aim to improve honey bee health.     

Effects of founder events on the genetic variation of translocated island populations: implications for conservation management of the northern quoll

Translocation is a strategy commonly used to maximize the persistence of threatened species, but it may sometimes lead to undesirable genetic consequences. The northern quoll (Dasyurus hallucatus) is a carnivorous marsupial that is critically endangered in Australia’s Northern Territory due to rapid population declines in areas recently colonized by the exotic cane toad Chaunus [Bufo] marinus. In 2003, 64 quolls were translocated to two offshore islands to establish insurance populations and reduce the species’ risk of extinction. In this study, we assessed genetic diversity at five microsatellite loci in the translocated populations, two endemic islands and three mainland populations. In the short-term (three generations), the translocated populations showed a slight but non-significant reduction in genetic diversity (A = 4.1–4.2; H _e = 0.56–0.59) compared to the mainland source populations (A = 5.0–8.4; H _e = 0.56–0.71). In comparison, high genetic erosion was observed in the endemic island populations (A = 1.5–2.9; H _e = 0.11–0.34). Genetic bottlenecks were detected on both endemic islands and in one mainland population, indicating recent reductions in population size. Our results are consistent with previous studies describing greater losses of genetic diversity on islands compared to mainland populations. Divergence from ancestral allele frequencies in the translocated populations also suggests effects due to founder events. This study, although short-term, highlights the importance of continued monitoring for detecting changes in genetic diversity over time and makes a significant contribution to our understanding of the effects of founder events on island populations.     

A molecular approach to understand the riddle of the invasive success of the tarantula,Brachypelma vagans,on Cozumel Island,Mexico

Invasive populations typically demonstrate genetic isolation which results in a loss of genetic diversity and a reduction in invasion success. This study focused on the genetic population of a successful invasive species of tarantula. Individuals were sampled in two mainland localities of the Yucatan Peninsula (Zoh-Laguna and Raudales), in addition to two island localities (El Cedral and Rancho Guadalupe on Cozumel Island). All populations present high genetic diversity (mean: H_e = 0.23, P = 99%), with significant differences between the Raudales and Rancho Guadalupe localities. The AMOVA analysis revealed a significant population structure (14.5% variation among populations), consistent with the gene differentiation coefficient (G_ST = 0.21), and spatial analysis of population structure. Our results suggested that the original introduced population did not suffer a loss of genetic diversity during establishment on the island, possibly a result of different biological conditions. Population structure analysis leads us to suggest that one island population is similar to the original genetic profile, whereas the genotypic profile of the other island population reflects recent introductions from the mainland. We identified a potential risk of extinction for one local mainland population, suggesting that this species may be a successful invader in a new environment but endangered in some parts of its natural area.     

The population genetics of two orchid bees suggests high dispersal,low diploid male production and only an effect of island isolation in lowering genetic diversity

Orchid bees (Hymenoptera, Apidae, Euglossini) are important pollinators of many plant families in Neotropical forests, habitats that have become increasingly degraded and fragmented by agricultural practices. To understand the extent to which loss of natural habitat and isolation has affected the genetic diversity and diploid male production (DMP) of two orchid bee species, Euglossa dilemma and Euglossa viridissima, we collected and genotyped 1686 males at five microsatellite loci and tested for differences in allelic richness, heterozygosity and DMP across three different types of land use (natural, agricultural and urban) and between mainland and island populations in the Yucatan Peninsula of Mexico. We also investigated the impact of land use and geographic isolation on gene flow. Euglossa dilemma and E. viridissima seemed to be particularly resilient to loss of natural habitat; in locations with human impact, we did not find reduced genetic diversity, and populations generally showed very little population genetic structure. Only on islands did E. dilemma show significantly reduced genetic diversity. Even after accounting for putative null alleles, DMP was very low (0.2–1.3%) across all sampling sites, including on islands. We therefore suggest that DMP is an insensitive measure of inbreeding and population decline in our two study species.     

Population Genetic Structure of the Invasive Red Swamp Crayfish in China Revealed by ITS1 Variation

The invasive red swamp crayfish (Procambarus clarkii) provides a valuable opportunity for studying the population genetics of invasive species that disperse rapidly. We analyzed the population genetic structure among 12 populations of the crayfish in China based on the internal transcribed spacer 1 (ITS1) region. The ITS1 of 815 bp aligned across 34 haplotypes; the average GC content was 53.9%. AMOVA showed that intrapopulation variation (95.26%) was much higher than interpopulation variation (4.74%). Genetic differentiation between the Taiwan and mainland populations (F _st = 0.160) was moderate, but the Chinese population (Taiwan and the mainland combined) and an American population were highly differentiated (0.682 and 0.977, respectively). Gene flow between the Chinese and American populations (N _m = 0.006 and 0.117, respectively) was lower than that between Taiwan and the mainland (1.536). Phylogenetic trees showed that three major genealogical clusters matched the sample locations well, suggesting that genetic differentiation is created largely by geographic isolation.     

Genetic variation and conservation of the endangered endemic Anagyris latifolia Brouss. ex Willd. (Leguminosae) from the Canary Islands

Anagyris latifolia is an endemic and endangered species from the Canary Islands, whose distribution is limited to four islands, with less than 400 individuals in fragmented and isolated localities. RAPD markers have been used to assess the genetic diversity and genetic differentiation of its populations, in order to formulate appropriate management and conservation genetics strategies. Nine polymorphic primers generated 74 polymorphic DNA fragments. Genetic variation levels detected in Anagyris latifolia were significant high (H = 0.200; P% = 97.3), principal coordinates analysis and genetic differentiation coefficient showed a high degree of genetic differentiation between islands, without a define east-to-west stepping stone colonization route. AMOVA analysis showed that of the total genetic variation detected, 32.43% was maintained among islands, 20.73% contained among population within islands, and 46.84% resided within populations. According to these results, management strategies should be focused on each island separately.     

Population genetic structure of orchid bees (Euglossini) in anthropogenically altered landscapes

Habitat degradation and fragmentation are widespread phenomena in tropical regions. Negative effects on the biota are numerous, ranging from interruption of gene flow among populations, to the loss of genetic diversity within populations, to a decline in species richness over time. Orchid bees (Hymenoptera: Apidae: Euglossini) are of major conservation interest due to their function as pollinators of numerous orchid species and other tropical plants. Here, we used microsatellite markers to investigate the effects of geographic distance and habitat fragmentation on gene flow among populations. Populations of Euglossa dilemma in three geographic regions??the Yucat??n peninsula (Mexico), Veracruz (Mexico), and Florida (USA)??were genetically structured predominantly across the regions, with the strength of differentiation among populations being positively correlated with geographic distance. Within geographic regions only little substructure was found, suggesting that dispersal is substantial in the absence of geographic or ecological barriers. In a second study, patterns of genetic differentiation among eight species of Euglossa were not related to habitat fragmentation following deforestation in southern Mexico (Veracruz). Specifically, most bee populations in the 9,800?ha forest remnant of Los Tuxtlas (Volcano San Martin) were neither differentiated from, nor had less genetic diversity than, populations in near-continuous forest separated from Los Tuxtlas by 130?km of agricultural land. Either occasional long distance dispersal across open areas has buffered the expected genetic effects of fragmentation, or the history of fragmentation in southern Mexico is too recent to have caused measurable shifts in allelic composition.     

Pollinating fig wasps: genetic consequences of island recolonization

The levels of genetic diversity and gene flow may influence the long-term persistence of populations. Using microsatellite markers, we investigated genetic diversity and genetic differentiation in island (Krakatau archipelago, Indonesia) and mainland (Java and Sumatra, Indonesia) populations of Liporrhopalum tentacularis and Ceratosolen bisulcatus, the fig wasp pollinators of two dioecious Ficus (fig tree) species. Genetic diversity in Krakatau archipelago populations was similar to that found on the mainland. Population differentiation between mainland coastal sites and the Krakatau islands was weak in both wasp species, indicating that the intervening 40 km across open sea may not be a barrier for wasp gene flow (dispersal) and colonization of the islands. Surprisingly, mainland populations of the fig waSPS may be more genetically isolated than the islands, as gene flow between populations on the Javan mainland differed between the two wasp species. Contrasting growth forms and relative 'immunity' to the effects of deforestation in their host fig trees may account for these differences.     

Gnaphalium teydeum and Gnaphalium luteo-album: two taxa of the Canary Islands with different genetic histories

Gnaphalium teydeum and G. luteo-album (Asteraceae) are two closely congeneric taxa native to the Canary Islands. While G. luteo-album is widespread in the Macaronesian Region, G. teydeum is endemic to the island of Tenerife and considered endangered by IUCN. Using the RAPD technique this study investigated the level and apportionment of genetic diversity of these taxa, trying to solve a taxonomic dispute related to G. teydeum. Based on the 102 DNA fragments generated by 11 primers, a high level of genetic differentiation was found between the taxa (F _ST  = 0.366), with G. luteo-album showing levels of genetic variability (P = 100%; H = 0.246) higher than those found in G. teydeum (P = 75.5%; H = 0.173). UPGMA dendrogram and Bayesian cluster analysis clearly separated populations from both the species. Overall, results show that although morphological differentiation between G. teydeum and G. luteo-album is not strong, they show marked molecular divergence, supporting the current taxonomic status.     

Genetic structure of island and mainland populations of a Neotropical bumble bee species

As a consequence of founder effects, small population size and demographic constraints, island populations are often characterized by low genetic diversity and high inbreeding. The effects of inbreeding are more pronounced in haplo-diploid insects like bees than in similar diploid species, because their method of sex determination requires heterozygosity at a sex locus. Inbreeding leads to homozygosity at the sex locus and the production of non-viable diploid males. This means that island populations of bees are particularly prone to extinction. Here we determine the levels of diversity and isolation between islands and mainland populations of the bumble bee Bombus morio in southeast Brazil. We analyzed 659 individuals from 24 populations, sequencing two mitochondrial genes (COI and Cytb) and genotyping all individuals at 14 microsatellite loci. Surprisingly, genetic diversity was high and genetic isolation was low in all populations except Teodoro Sampaio (mainland) and Ilha da Vitória (island). Genetic diversity is not significantly correlated with island area, but is lower in populations that are more distant from the mainland. Except perhaps for Ilha da Vitória, we suggest that the island populations are unlikely to go extinct due to genetic factors. Finally, based on its genetic distance from all other populations, we identify a putative new subspecies in the Teodoro Sampaio region.     

Genetic diversity and structure of Lilium pumilum DC. in southeast of Qinghai–Tibet plateau

Lilium pumilum DC. is a valuable species not only for its showy flowers but also for its edible and medicinal values. As one of the distribution areas of L. pumilum, Qinghai–Tibet plateau has unique environmental features which have high impact on the evolution of the species. No population genetic studies have been done for L. pumilum so far. To provide the first reference data for evolutionary study and understanding the influence of eco-geographic factors on the distribution of genetic variation in L. pumilum, interspecific simple sequence repeat markers were used to investigate genetic diversity and population structure of 28 populations sampled from southeast of Qinghai–Tibet plateau. Fifteen selected primers generated a total of 147 polymorphic bands. The genetic diversity was low within populations (average He = 0.173), but higher at the species level (He = 0.392). A clear population structure and high level of genetic differentiation (F _ST = 0.518) were detected by unweighted pair group method for arithmetic averages, principle coordinate analysis and Bayesian clustering. All clustering approaches supported a division of the 28 populations into 4 major groups for which analysis of molecular variance confirmed a significant variation among groups (34.3 %). These population genetic parameters suggest limited gene flow among populations and evidence for isolation by distance (r = 0.272, P < 0.0001) was found in this study. Altitude, AMT and AMP explained 9.5, 11.5 and 14.0 % of the total variance among populations indicating that eco-geographic factors have a significant effect. Considering the low within-population genetic diversity, high differentiation among populations and the increasing anthropogenic pressure on the species, in situ conservation measures were recommended to preserve L. pumilum in Qinghai–Tibet plateau.     

High level of genetic variation within clonal orchid Goodyera repens

Type of reproduction has an important effect on the maintenance of particular populations and species persistence in time and space. This trait significantly influences the ecological and genetic structure of populations, and in consequence the evolution of species. The primary objectives of this study were: to estimate genetic diversity within and among populations of clonal species Goodyera repens from different populations in northeastern Poland, and to amount factors shaping the genetic structure of this orchid. Based on 451 rosettes of G. repens from 11 localities in northeastern Poland, we conducted a genetic population analysis using allozymes. We included information on population size, flowering, fruit set and seed dispersal to elucidate their influences on genetic diversity of this species. Populations differed according to demographic properties. The majority of seeds (86.4–94.8 %) were found at a distance of 0.2 m. We observed a high level of genetic (P _PL = 50 %, A = 1.68, H _O = 0.210, H _E = 0.204) and genotypic diversity (G = 163, G/N _S = 0.66, G _U = 30.2 %), and low but statistically significant genetic differentiation among populations (F _ST = 0.060; P < 0.001). We suggest that the genetic diversity of G. repens is mainly an effect of the abundance of pine and spruce forest communities suitable for this species in NE Poland and the high level of sexual reproduction.     

Phylogenetic relationships of the Chalcides skink species from the Chafarinas Islands with those from mainland North Africa

Species whose geographical distribution encompasses both mainland and island populations provide ideal systems for examining potential isolation and genetic divergence. This has also interest from a conservationist point of view, as it is important to protect “evolutionarily significant units”. We report a phylogenetic mitochondrial DNA analysis comparing the populations of the three Chalcides skink species from the Chafarinas Islands (NW Africa) with specimens of the same species from the nearest mainland. We tested for the potential genetic distinctiveness of the skink island populations. However, the results of the comparison of the genetic variability of the mitochondrial coding gene cytb were conclusive showing that the genetic divergence between continental and island Chalcides species was either non-existent or extremely low. We discuss how genetic divergence may be lower than expected if separation time of the islands with the mainland has not been long enough or if the island skink populations were currently communicated via ocean rafting with individuals coming from the mainland ones.     

High genetic diversity detected in the endemic Primula apennina Widmer (Primulaceae) using ISSR fingerprinting

Primula apennina Widmer is endemic to the North Apennines (Italy). ISSR were used to detect the genetic diversity within and among six populations representative of the species distribution range. High levels of genetic diversity were revealed both at population percentage of polymorphic band (PPB = 75.92%, H _S = 0.204, H _pop = 0.319) and at species level (PPB = 96.95%, H _T = 0.242, H _sp = 0.381). Nei gene diversity statistics (15.7%), Shannon diversity index (16.3%) and AMOVA (14%) detected a moderate level of interpopulation diversity. Principal coordinate and Bayesian analyses clustered the populations in three major groups along a geographic gradient. The correlation between genetic and geographic distances was positive (Mantel test, r = 0.232). All together, these analyses revealed a weak but significant spatial genetic structure in P. apennina, with gene flow acting as a homogenizing force that prevents a stronger differentiation of populations. Conservation measures are suggested based on the observed pattern of genetic variability.     

Conservation genetics of the annual hemiparasitic plant <Emphasis Type="Italic">Melampyrum sylvaticum</Emphasis> (Orobanchaceae) in the UK and Scandinavia

Melampyrum sylvaticum is an endangered annual hemiparasitic plant that is found in only 19 small and isolated populations in the United Kingdom (UK). To evaluate the genetic consequences of this patchy distribution we compared levels of diversity, inbreeding and differentiation from ten populations from the UK with eight relatively large populations from Sweden and Norway where the species is more continuously distributed. We demonstrate that in both the UK and Scandinavia, the species is highly inbreeding (global F _IS = 0.899). Levels of population differentiation were high (F’_ST = 0.892) and significantly higher amongst UK populations (F’_ST = 0.949) than Scandinavian populations (F’_ST = 0.762; P < 0.01). The isolated populations in the UK have, on average, lower genetic diversity (allelic richness, proportion of loci that are polymorphic, gene diversity) than Scandinavian populations, and this diversity difference is associated with the smaller census size and population area of UK populations. From a conservation perspective, the naturally inbreeding nature of the species may buffer the species against immediate effects of inbreeding depression, but the markedly lower levels of genetic diversity in UK populations may represent a genetic constraint to evolutionary change. In addition, the high levels of population differentiation suggest that gene flow among populations will not be effective at replenishing lost variation. We thus recommend supporting in situ conservation management with ex situ populations and human-mediated seed dispersal among selected populations in the UK.     

Chloroplast microsatellite diversity of Opisthopappus Shih (Asteraceae) endemic to China

The genus Opisthopappus consists of two species, O. longilobus and O. taihangensis. Both of them are important economic and ornamental plants but endangered in China. In this study, genetic variation in four populations of O. longilobus and nine populations of O. taihangensis was estimated by chloroplast microsatellites (cpSSR). Low genetic diversity was detected in O. longilobus and O. taihangensis populations. The percentages of polymorphic loci (PPL), Nei’s gene diversities (h), and Shannon’s indices (I) was 53.56 %, 0.074, and 0.139, respectively, for O. longilobus, while PPL = 44.44 %, h = 0.018, I = 0.048 for O. taihangensis. Thirteen chloroplast haplotypes were identified from 153 individuals analyzed of two species. Ten haplotypes were found in O. longilobus, while seven in O. taihangensis. Haplotype 1 was the common and ancestral one. The level of haplotype diversity was also low (Hd _{O. longilobus}  = 0.4875, Hd _{O. taihangensis}  = 0.3452). AMOVA analysis revealed that the majority of the genetic differences was partitioned within populations of O. longilobus and O. taihangensis, as confirmed by PCoA and cluster analysis. Inter-population genetic distances among population of O. longilobus and O. taihangensis correlated insignificantly with geographic distances (r = 0.286, P = 0.128 for O. longilobus vs. r = 0.356, P = 0.058 for O. taihangensis). The self-compatibility, effective gene flow, narrow geographical distribution, and historical factors may be the main factors causing differentiation in the genetic structure of O. longilobus and O. taihangensis populations.     

Genetic diversity of the endangered Chinese endemic herb Saruma henryi Oliv. (Aristolochiaceae) and its implications for conservation

Saruma henryi Oliv., the only representative of the monotypic genus Saruma Oliv. (Aristolochiaceae), is an endangered perennial herb endemic to China. It is a phylogenetically, ecologically, and medicinally important species. In the present study, inter-simple sequence repeat (ISSR) markers were employed to investigate the genetic diversity and differentiation of 14 populations. A total of 16 selected primers yielded 175 bright and discernible bands, with an average of 10.94 per primer. POPGENE analysis showed that the genetic diversity was quite low at the population level (h = 0.0447–0.1243; I = 0.0642–0.1853; PPB = 10.29–36.57%), but pretty high at the species level (h = 0.2603; I = 0.3857; PPB = 73.71%). The hierarchical analysis of molecular variance (AMOVA) revealed a high level of genetic differentiation among populations (67.18% of total variance components, P < 0.001), in line with the gene differentiation coefficient (G _ST = 0.6903) and the limited among-population gene flow (N _m = 0.2243). Both Principal Coordinates Analysis (PCoA) and UPGMA cluster analysis supported the grouping of all 14 populations into three geographic groups, among which there occurred a moderate level of genetic differentiation (33.18% of total variance components, P < 0.001) as shown by AMOVA analysis. In addition, Mantel test revealed a significant correlation between genetic and geographic distances among populations (r = 0.7792, P = 0.001), indicating the role of geographic isolation in shaping its present population genetic structure. The present levels and patterns of genetic diversity of S. henryi were assumed to result largely from its breeding system, geographic isolation, clonal growth, its unique biological traits and evolutionary history. The high genetic differentiation among populations implies that the conservation efforts should aim to preserve all the extant populations of this endangered herb.     

Genetic structure of the critically endangered plant Tricyrtis ishiiana (Convallariaceae) in relict populations of Japan

Tricyrtis ishiiana is a relic endemic plant taxon of the Convallariaceae that inhabits two nearby gorges in Kanagawa Prefecture, Japan. The distribution range and number of populations are thought to have been reduced to the present refugial populations during the Quaternary climatic oscillations. Because of its showy flowers, this plant has faced illegal removal from its natural habitats for horticultural use and has been designated a critically endangered species (class IA). In this study, we analyzed the genetic structure of the relict populations of T. ishiiana in order to contribute to the conservation strategies of the prefectural government. Our analyses of nine nuclear microsatellite loci detected high genetic diversity (H _E = 0.704 and H _O = 0.541) for the two populations. The two populations were slightly differentiated (R _ST = 0.032), accompanied by faint substructure across the populations (K = 3). In addition, each population exhibited spatial genetic structuring. The relatively low inbreeding coefficient for both populations together (F _IS = 0.233) and each population separately (F _IS = 0.217?C0.246) may be attributable to crossing among descendants within a population along with occasional gene flow between the populations. These results suggested that the extant populations have not experienced a severe bottleneck. The two extant populations were genetically differentiated at a very low level, accompanied by occasional pollen flow via pollinators and/or seed dispersal by gravity in the mountainous environment. Occasional gene exchange between the populations has allowed T. ishiiana to harbor high genetic diversity despite being a relic plant confined to two small refugial populations.     

Elucidating the multiple genetic lineages and population genetic structure of the brooding coral <Emphasis Type="Italic">Seriatopora</Emphasis> (Scleractinia: Pocilloporidae) in the Ryukyu Archipelago

The elucidation of species diversity and connectivity is essential for conserving coral reef communities and for understanding the characteristics of coral populations. To assess the species diversity, intraspecific genetic diversity, and genetic differentiation among populations of the brooding coral Seriatopora spp., we conducted phylogenetic and population genetic analyses using a mitochondrial DNA control region and microsatellites at ten sites in the Ryukyu Archipelago, Japan. At least three genetic lineages of Seriatopora (Seriatopora-A, -B, and -C) were detected in our specimens. We collected colonies morphologically similar to Seriatopora hystrix, but these may have included multiple, genetically distinct species. Although sexual reproduction maintains the populations of all the genetic lineages, Seriatopora-A and Seriatopora-C had lower genetic diversity than Seriatopora-B. We detected significant genetic differentiation in Seriatopora-B among the three populations as follows: pairwise F _ST = 0.064–0.116 (all P = 0.001), pairwise G′′_ST = 0.107–0.209 (all P = 0.001). Additionally, only one migrant from an unsampled population was genetically identified within Seriatopora-B. Because the peak of the settlement of Seriatopora larvae is within 1 d and almost all larvae are settled within 5 d of spawning, our observations may be related to low dispersal ability. Populations of Seriatopora in the Ryukyu Archipelago will probably not recover unless there is substantial new recruitment from distant populations.