Guidelines for the restoration of the tropical timber tree <Emphasis Type="Italic">Anacardium excelsum</Emphasis>: first input from genetic data

Translocation of trees has been used as a common method to mediate genetic conservation and restoration of forests. However, very few programs include strategies developed to recover or maintain the genetic diversity of the translocated species. Anacardium excelsum is a tree native to the tropics of America that is extensively used in forestry. In Colombia, restoration of forests through the translocation of native species has regained importance, and A. excelsum has been recently included in the National Strategy for Plant Conservation. Thus, in order to define the level of genetic structure and the level of genetic diversity within certain regions where remnants of the seasonally dry tropical forests (SDTF) of Colombia have been retained, we genotyped 106 trees using nuclear inter-simple sequence repeats (ISSR) and sequenced two non-coding chloroplast loci for these specimens. Our ISSR dataset revealed the existence of a gradient in genetic diversity within A. excelsum with the most diverse remnants encountered in the south of the country, while the localities sampled in the Caribbean coast and in the Chicamocha canyon were less diverse. Chloroplast loci also pointed out the very low genetic diversity of A. excelsum from the Chicamocha canyon and we propose to prioritize this area within future conservation programs. Both chloroplast and nuclear markers supported the existence of genetic divergence between distinct regions of Colombia, uncovering genetic differences between inter-Andean, Caribbean, and Chicamocha canyon A. excelsum remnants. Hence, we advise to choose the provenance of seeds or plants carefully before translocation and to consider minimal mixing of material from different regions when initializing restoration programs for A. excelsum, in Colombia.     

<Emphasis Type="Italic">Quinua</Emphasis> and Relatives (<Emphasis Type="Italic">Chenopodium</Emphasis> sect.<Emphasis Type="Italic">Chenopodium</Emphasis> subsect.<Emphasis Type="Italic">Celluloid</Emphasis>)

Traditionally viewed as an Andean grain crop,Chenopodium quinoa Willd. includes domesticated populations that are not Andean, and Andean populations that are not domesticated. Comparative analysis of leaf morphology and allozyme frequencies have demonstrated that Andean populations, both domesticated(quinua) and free-living(ajara), represent an exceptionally homogeneous unit that is well differentiated from allied domesticates of coastal Chile(quingua) and freeliving populations of the Argentine lowlands(C. hircinum). This pattern of relationships indicates that Andean populations represent a monophyletic crop/weed system that has possibly developed through cyclic differentiation (natural vs. human selection) and introgressive hybridization. Relative levels of variation suggest that this complex originated in the southern Andes, possibly from wild types allied withC. hircinum, with subsequent dispersal north to Colombia and south to the Chilean coast. Coastal populations were apparently isolated from post-dispersal differentiation and homogenization that occurred in the Andes. Other data point toward a center of origin in the northern Andes with secondary centers of genetic diversity subsequently developing in the southern Andes and the plains of Argentina. Comparative linkage of South American taxa, all tetraploid, with North American tetraploids of the subsection will eventually clarify this problem. While the possibility of a direct phyletic connection betweenC. quinoa and the Mexican domesticate(C. berlandieri subsp. nuttalliae,) cannot be excluded, available evidence indicates that the latter represents an autonomous lineage that is associated with the basal tetraploid, C. b. subsp.berlandieri, through var.sinuatum, whereas South American taxa show possible affinities to either var. zschackei or var.berlandieri. An extinct domesticate of eastern North America,C. b. subsp.jonesianum, represents either another instance of independent domestication, possibly from subsp. b. var.zschackei, or a northeastern outlier of subsp.nuttalliae.     

Distribution,population density and conservation of the critically endangered brown spider monkey (<Emphasis Type="Italic">Ateles hybridus</Emphasis>) and other primates of the inter-Andean forests of Colombia

The inter-Andean tropical rainforests and dry forests of the Magdalena river basin (Tumbes-Choco-Magdalena biodiversity hotspot) in northern Colombia have undergone significant forest loss and degradation in recent decades. Six primate species inhabit this region, five of which are currently threatened with extinction and one of which—the brown spider monkey, Ateles hybridus—is considered critically endangered. Accurate and recent information on the distribution and conservation status of these threatened primate populations is scarce or nonexistent, even though such data are needed to implement successful conservation actions and management plans. Between 2006 and 2016, we evaluated the status and distribution of primates across inter-Andean lowland forests in northern Colombia. We visited 30 sites to evaluate the presence/absence of brown spider monkeys and other primate taxa in the region. We also carried out surveys at 10 of these sites to obtain estimates of primate population densities and demographic information from forests with different levels of anthropogenic disturbance. Novel data on primate presence/absence were obtained for 27 sites, and 136 records were collected in total. Only 33% of the sites visited were large forest fragments (>?500 Ha). This study confirms that at least six primate species are still present in the Rio Magdalena region, which represents the highest platyrrhine diversity west of the Andes. This study also confirms the persistence of a wild population of Colombian woolly monkeys (Lagothrix lagotricha lugens) in the Serranía de San Lucas. Assigning formal protected status to this region is an urgent priority for the conservation of primates in the Rio Magdalena region.     

Otolith variation in Pacific herring (<Emphasis Type="Italic">Clupea pallasii</Emphasis>) reflects mitogenomic variation rather than the subspecies classification

Pacific herring (Clupea pallasii) is divided into three subspecies: two in northeast Europe and one in the north Pacific Ocean. Genetic studies have indicated that the populations in northeast Europe have derived from the northwest Pacific herring recently, or during the last 10–15 kyr, and that they are distinct from the population in the northeast Pacific. In addition, hybridization between the Pacific herring and the Atlantic herring has been documented. Otolith variation has been considered to be largely affected by environmental variation, but here we evaluate whether the genetic differentiation is reflected in otolith shape differences. A clear difference in otolith shape was observed between the genetically differentiated herring species Clupea harengus from the Atlantic and C. pallasii. The otolith shape of C. p. suworowi in the Barents Sea was different from the shape of C. pallasii in northern Norway and C. p. pallasii from the Pacific. Populations of C. p. pallasii, sampled east and west of the Alaska Peninsula, which belong to two genetically different clades of the C. p. pallasii in the Pacific Ocean, show a clear difference in otolith shape. C. p. suworowi and the local C. pallasii peripheral population in Balsfjord in northern Norway are more similar to the northwest Pacific herring (C. p. pallasii) than to the northeast Pacific herring (C. p. pallasii), both genetically and in otolith shape. The Balsfjord population, known to be influenced by introgression of mtDNA from the Atlantic herring, does not show any sign of admixture in otolith shape between the two species. A revised classification, considering the observed genetic and morphological evidence, should rather group the northwest Pacific herring in the Bering Sea together with the European populations of C. pallasii than with the northeast Pacific herring in the Gulf of Alaska.     

Signatures of invasion: using an integrative approach to infer the spread of melon fly, <Emphasis Type="Italic">Zeugodacus cucurbitae</Emphasis> (Diptera: Tephritidae), across Southeast Asia and the West Pacific

Invasion into new areas by already widespread pest organisms often occurs through non-obvious routes, with the origins of such invasions difficult to determine. Understanding population structure using multiple datatypes can help untangle past dispersal events and reveal putative contemporary invasion pathways. The tephritid fruit fly, Zeugodacus cucurbitae (Coquillett), is a serious pest of cucurbits and other commercial crops and is considered native to the Indo-Oriental region, but is invasive in both Africa and the Pacific. Here, we combine molecular (microsatellites and COI) and morphological (male genetalia length and wing shape geometric morphometrics) data within an integrative taxonomic framework to test hypotheses concerning levels of Z. cucurbitae population variation observed in Southeast Asia (native range, 10 sites, ~200 individuals) versus the West Pacific (invasive range, 4 sites, ~80 individuals), and whether single or multiple introductions of Z. cucurbitae have occurred into the West Pacific. We also use this case to explicitly test if using an integrative approach provides more information about hypothesized invasion pathways than either genetic or morphological approaches would do alone. All datasets support Z. cucurbitae as being more variable in Southeast Asia than the West Pacific, and within these regions populations appear to be structured geographically. In particular, mainland and Sundaic Southeast Asian locations formed separate clusters, and New Guinea and Solomon Islands were not closely related to Guam and Hawaii. Evidence supports a separate single origin for New Guinea from the Melanesian arc, the Solomon Islands from Malaysia/Singapore, and Guam from mainland Asia, but multiple introductions into Hawaii from mainland Asia. Taken together, we argue that there is great value in integrating evidence from multiple sources as it can provide finer resolution of population relationships than any single data source alone.     

The <Emphasis Type="Italic">Diatraea</Emphasis> Complex (Lepidoptera: Crambidae) in Colombia’s Cauca River Valley: Making a Case for the Geographically Localized Approach

The sugarcane stem borers Diatraea saccharalis (Fabricius) and D. indigenella Dyar & Heinrich are common pests of sugarcane crops in Colombia’s Cauca river valley (CRV). In 2012, however, D. tabernella Dyar was recorded for the first time in northern CRV and just 1 year later, D. busckella Dyar & Heinrich was detected, also for the first time, in central CRV. The Diatraea outbreak in the CRV was studied, its distribution and population in the region was analyzed, and levels of larval parasitism were observed. During the study of the outbreak, Diatraea species in the CRV were characterized based on the morphology of larval, pupal, and adult stages. Keys to the identification of Diatraea in the CRV based on male genitalia and pupa are provided. Pupal cephalic horns and lateral lobes were discovered as new, reliable characteristics to separate the species at the pupal stage. We suggest biological control program modifications to decrease economic impact and studies at geographically localized levels to better understand the dynamics between the pest species and their parasitoids.     

<Emphasis Type="Italic">Drosophila suzukii</Emphasis> in Southern Neotropical Region: Current Status and Future Perspectives

Non-native insect pests are often responsible for important damage to native and agricultural plant hosts. Since Drosophila suzukii Matsumura (Diptera: Drosophilidae) has become an important pest in North America and Europe (i.e., in 2008), the global production of soft thin-skinned fruits has faced severe production losses. In the southern Neotropical region, however, the first record of D. suzukii occurred in 2013 in the south of Brazil. It has also been recorded in Uruguay, Argentina, and Chile. Despite its recent occurrence in the southern Neotropical region, the fast dispersion of D. suzukii has inspired local research efforts in an attempt to mitigate the consequences of this insect pest invasion. In this forum, we explore the current status of D. suzukii in southern Neotropical regions, discussing its future perspectives. Additionally, we attempt to draft activities and a research agenda that may help to mitigate the losses caused by D. suzukii in native and commercial soft-skinned fruits produced in this region. Currently, D. suzukii appears to be well established in the south of Brazil, but considering the entire southern Neotropical region, the invasion panorama is still underinvestigated. The lack of studies and regulatory actions against D. suzukii has contributed to the invasion success of this species in this region. Considering several peculiarities of both the pest biology and the environmental of this region, the authors advocate for the need of intensive and integrative studies toward the development and implementation of area-wide integrated pest management programs against D. suzukii in the southern Neotropical region.     

Preliminary data on the variability of three microsatellite loci in Pacific <Emphasis Type="Italic">Gadus macrocephalus</Emphasis> and Atlantic <Emphasis Type="Italic">G. morhua</Emphasis> cod (Gadidae)

Variability of microsatellite DNA loci Gmo3, Gmo34, and Gmo35 is studied in samples of Pacific cod Gadus macrocephalus and Atlantic cod G. morhua. The results show high values of identity of the samples within the North Pacific basin (0.9766–0.9924) and within the Northeast Atlantic basin (0.9580). Based on the pairwise assessment of genetic differentiation, the F _ST values are significantly different in all variants between the samples of Pacific and Atlantic cod (F _ST = 0.5235–0.6719, p < 0.001). Within the basins, the significant differences in the frequencies of main alleles are revealed in the loci Gmo3 and Gmo34 for the samples from the Pacific and Atlantic oceans, respectively.     

An endangered hemiparasitic shrub is the only host plant of the little-known Neotropical hairstreak <Emphasis Type="Italic">Strymon flavaria</Emphasis> (Lepidoptera: Lycaenidae) in the arid Andes

Larval host plants can be the main resource underlying the distribution (including altitudinal ranges) of specialized phytophagous insects such as butterflies. Strymon flavaria (Ureta) (Lepidoptera: Lycaenidae: Theclinae: Eumaeini) is a little-known hairstreak endemic to the arid belt at about 3000–3500 m elevation on the western slopes of the Andes of northern Chile. The hemiparasitic shrub Krameria lappacea (Dombey) Burdet and Simpson is here recorded as the first host plant known for S. flavaria, representing also the first record of the association of a species of Strymon Hübner with the plant family Krameriaceae. Females of S. flavaria lay eggs on flower buds and unripe fruits of K. lappacea; the larva eats mostly these plant organs. Field observations revealed that S. flavaria is a host-specialist hairstreak, since females lay eggs only on K. lappacea. These findings suggest that the altitudinal range of S. flavaria could be the result of its specialized association with K. lappacea, as this shrub is also mostly restricted to elevations above 3000 m in the Andes of northern Chile. The implications of this finding for the ecology and conservation of S. flavaria are discussed.     

Re-evaluation of <Emphasis Type="Italic">Psidium acutangulum</Emphasis> (Myrtaceae) and a new combination in <Emphasis Type="Italic">Psidium</Emphasis>

Psidium acutangulum has been previously understood as a widespread and variable species. Here, it is proposed that populations east of the Andes should be divided into two species: P. acutangulum and P. acidum based on characters of the leaves, anthers, fruits and seeds. The new combination Psidium acidum is made here and the species is described, illustrated and contrasted with P. acutangulum and P. friedrichsthalianum. Psidium acutangulum as now understood remains variable and seems to be related to a mainly Amazonian group of species. Populations from western Ecuador, once thought to belong to P. acutangulum are now considered a new species.     

Population structure and variability of Pacific herring (<Emphasis Type="Italic">Clupea pallasii</Emphasis>) in the White Sea,Barents and Kara Seas revealed by microsatellite DNA analyses

Pacific herring, Clupea pallasii, have recently colonised the northeast Atlantic and Arctic Oceans in the early Holocene. In a relatively short evolutionary time, the herring formed a community with a complex population structure. Previous genetic studies based on morphological, allozyme and mitochondrial DNA data have supported the existence of two herring subspecies from the White Sea and eastern Barents and Kara Seas (C. p. marisalbi and C. p. suworowi, respectively). However, the population structure of the White Sea herring has long been debated and remains controversial. The analyses of morphological and allozyme data have previously identified local spawning groups of herring in the White Sea, whereas mtDNA markers have not revealed any differentiation. We conducted one of the first studies of microsatellite variation for the purpose of investigating the genetic structure and relationship of Pacific herring among ten localities in the White Sea, the Barents Sea and the Kara Sea. Using classical genetic variance-based methods (hierarchical AMOVA, overall and pairwise F _ST comparisons), as well as the Bayesian clustering, we infer considerable genetic diversity and population structure in herring at ten microsatellite loci. Genetic differentiation was the most pronounced between the White Sea (C. p. marisalbi) versus the Barents and Kara seas (Chesha–Pechora herring, C. p. suworowi). While microsatellite variation in all C. pallasii was considerable, genetic diversity was significantly lower in C. p. suworowi, than in C. p. marisalbi. Also, tests of genetic differentiation were indicating significant differentiation within the White Sea herring between sympatric summer- and spring-spawning groups, in comparison with genetic homogeneity of the Chesha–Pechora herring.     

Survey of Pathogenic Chytrid Fungi (<Emphasis Type="Italic">Batrachochytrium dendrobatidis</Emphasis> and <Emphasis Type="Italic">B. salamandrivorans</Emphasis>) in Salamanders from Three Mountain Ranges in Europe and the Americas

Batrachochytrium salamandrivorans (Bsal) is a virulent fungal pathogen that infects salamanders. It is implicated in the recent collapse of several populations of fire salamanders in Europe. This pathogen seems much like that of its sister species, Batrachochytrium dendrobatidis (Bd), the agent responsible for anuran extinctions and extirpations worldwide, and is considered to be an emerging global threat to salamander communities. Bsal thrives at temperatures found in many mountainous regions rich in salamander species; because of this, we have screened specimens of salamanders representing 17 species inhabiting mountain ranges in three continents: The Smoky Mountains, the Swiss Alps, and the Peruvian Andes. We screened 509 salamanders, with 192 representing New World salamanders that were never tested for Bsal previously. Bsal was not detected, and Bd was mostly present at low prevalence except for one site in the Andes.     

Population Genomics Reveals Genetic Divergence and Adaptive Differentiation of Chinese Sea Bass (<Emphasis Type="Italic">Lateolabrax maculatus</Emphasis>)

The marine species usually show high dispersal capabilities accompanied by high levels of gene flow. On the other hand, many physical barriers distribute along the continental marginal seas and may prevent dispersals and increase population divergence. These complexities along the continental margin generate serious challenges to population genetic studies of marine species. Chinese sea bass Lateolabrax maculatus distributes broad latitudinal gradient spanning from the tropical to the mid-temperate zones in the continental margin seas of the Northwest Pacific Ocean. Using the double digest restriction-site-associated DNA tag sequencing (ddRAD) approach, we genotyped 10,297 SNPs for 219 Chinese seabass individuals of 12 populations along the Chinese coast in the Northwest Pacific region. Genetic divergence among these populations was evaluated, and population structure was established. The results suggested that geographically distant populations in the Bohai Gulf and the Beibu Gulf retain significant genetic divergence, which are connected by a series of intermediate populations in between. The results also suggested that Leizhou Peninsula, Hainan Island, and Shandong Peninsula are major physical barriers and substantially block gene flow and genetic admixture of L. maculatus. We also investigated the potential genetic basis of local adaptation correlating with population differentiation of L. maculatus. The sea surface temperature is a significantly differentiated environmental factor for the distribution of L. maculatus. The correlation of water temperature and genetic variations in extensively distributed populations was investigated with Bayesian-based approaches. The candidate genes underlying the local selection in geographically divergent populations were identified and annotated, providing clues to understand the potential mechanisms of adaptive evolution. Overall, our genome scale population genetic analysis provided insight into population divergence and local adaptation of Chinese sea bass in the continental marginal seas along Chinese coast.     

A morphological and phylogenetic analysis of <Emphasis Type="Italic">Ornithodoros marinkellei</Emphasis> (Acari: Argasidae), with additional notes on habitat and host usage

Ornithodoros marinkellei was described from larvae collected on Pteronotus spp. bats in Colombia and Panama. More recently, this tick was reported in the Brazilian Amazon. Because some morphometric differences were observed between O. marinkellei larvae from Colombia and Brazil, it was proposed that further investigations were needed to assess whether the differences could be attributed to intra- or inter-specific polymorphism. Herein, we collected O. marinkellei specimens in the type locality of Colombia, in Brazil, and in a new locality in Nicaragua, expanding the distribution of the species to Nicaragua. Morphometric analysis of larvae and adults, corroborated by a principal component analysis (PCA), indicated that the Brazilian specimens were larger than specimens from Colombia and Nicaragua. Phylogenetic analysis inferred from the mitochondrial 16S rRNA gene showed ticks from Colombia and Nicaragua more genetically related than any of them with ticks from Brazil, although ticks from the three countries grouped in a clade sister to a major clade containing sequences of various Neotropical Ornithodoros species. We concluded that ticks identified as O. marinkellei from Colombia, Nicaragua, and Brazil represent the same taxon, and that the genetic and morphological differences between them are likely to have a geographical bias. We redescribed the nymph of O. marinkellei, which has a vestigial hypostome, probably incompatible with blood feeding. We also report human infestation by O. marinkellei adults. As all reports of O. marinkellei adults have been from hot caves (temperature?>?35 °C), this abiotic condition could be a limiting factor for the occurrence of this tick species.     

Phenotypic,Genetic, and Cytogenetic Evidence of Hybridization Between Species of Trans-Andean Tamarins (Genus <Emphasis Type="Italic">Saguinus</Emphasis>)

Incomplete reproductive isolation and hybridization is relatively frequent in primates. However, no cases of hybridization between formally recognized species have been reported in tamarins (genus Saguinus), a highly specious group of Neotropical primates. Here, we provide evidence from different sources to demonstrate three cases of hybridization in captivity between species of Saguinus distributed west of the Andes (trans-Andean). To do this, we described fur color patterns, genotyped 12 microsatellite loci, sequenced the mitochondrial hypervariable region I, and generated chromosomal R bands for the three formally recognized species and the new hybrids of trans-Andean tamarins. We identified one case of interbreeding between the white-footed tamarin (Saguinus leucopus) and the cotton-top tamarin (S. ?dipus) and two independent reciprocal crosses of S. leucopus and the Geoffroy’s tamarin (S. geoffroyi). All these hybrids exhibit intermediate phenotypes between parental species, and genetic data are consistent with first-generation hybridization. Cytogenetic data suggest that the S. leucopus × S. ?dipus hybrid is sterile, as it is a female with XY karyotype apparently affected by a condition known as gonadal dysgenesis. Trans-Andean tamarin species occur in northwest Colombia with parapatric distributions bounded by major rivers. Potential contact zones, either natural or anthropogenic, might facilitate hybridization in the wild, but this scenario remains to be assessed. Our findings warrant future studies focused on the evolutionary mechanisms of reproductive isolation in tamarins. Given the risk of hybridization, caution should be taken in management and conservation of tamarins.     

Development,genetic and cytogenetic analyses of genetic sexing strains of the Mexican fruit fly, <Emphasis Type="Italic">Anastrepha ludens</Emphasis> Loew (Diptera: Tephritidae)

Background

Anastrepha ludens is among the pests that have a major impact on México's economy because it attacks fruits as citrus and mangoes. The Mexican Federal government uses integrated pest management to control A. ludens through the Programa Nacional Moscas de la Fruta [National Fruit Fly Program, SAGARPA-SENASICA]. One of the main components of this program is the sterile insect technique (SIT), which is used to control field populations of the pest by releasing sterile flies.

Results

To increase the efficiency of this technique, we have developed a genetic sexing strain (GSS) in which the sexing mechanism is based on a pupal colour dimorphism (brown-black) and is the result of a reciprocal translocation between the Y chromosome and the autosome bearing the black pupae (bp) locus. Ten strains producing wild-type (brown pupae) males and mutant (black pupae) females were isolated. Subsequent evaluations for several generations were performed in most of these strains. The translocation strain named Tapachula-7 showed minimal effect on survival and the best genetic stability of all ten strains. Genetic and cytogenetic analyses were performed using mitotic and polytene chromosomes and we succeeded to characterize the chromosomal structure of this reciprocal translocation and map the autosome breakpoint, despite the fact that the Y chromosome is not visible in polytene nuclei following standard staining.

Conclusions

We show that mitotic and polytene chromosomes can be used in cytogenetic analyses towards the development of genetic control methods in this pest species. The present work is the first report of the construction of GSS of Anastrepha ludens, with potential use in a future Moscafrut operational program.

     

Population genetic analysis of Euro-Arctic polar cod <Emphasis Type="Italic">Boreogadus saida</Emphasis> suggests fjord and oceanic structuring

Polar cod, Boreogadus saida, is a key species in Arctic marine ecosystems; however, its genetic population structure is largely undescribed. The population genetic structure of 472 B. saida specimens among nine locations in the north-east Atlantic was revealed using 12 microsatellite loci. Pairwise F _ST comparisons showed significant population differentiation between B. saida sampled inside fjords in Svalbard and north-east Greenland, as compared to B. saida from the shelf. The observed genetic variation was not a function of isolation by distance, and it is speculated that B. saida populations inhabiting fjords may have become reproductively isolated from shelf-dwelling B. saida during the last post-glacial recolonization.     

A geometric morphometric and microsatellite analyses of <Emphasis Type="Italic">Scaptotrigona mexicana</Emphasis> and <Emphasis Type="Italic">S. pectoralis</Emphasis> (Apidae: Meliponini) sheds light on the biodiversity of Mesoamerican stingless bees

Geometric morphometrics and molecular methods are effective tools to study the variability of stingless bee populations and species that merit protection given their worldwide decline. Based on previous evidence of cryptic lineages within the Scaptotrigona genus, we tested the existence of multiple evolutionary lineages within the species S. mexicana and we investigated the status of S. pectoralis. By analyzing their population structure, we found differences between the Pacific and Atlantic populations of each of these species, although geometric morphometrics of the wing only confirmed these results in S. mexicana. There was a tendency towards enhanced genetic differentiation over larger distances in the Atlantic populations of both species but not in the Pacific populations. These results revealed a pattern of differentiation among evolutionary units and a specific distribution of genetic diversity within these Scaptotrigona species in Mesoamerica, suggesting the need for future taxonomic revisions, as well as activities aimed at management and conservation.