Acurio, Andrea E

ACURIO A.E.

Huber B.A., Meng G., Acurio A.E., Astrin J.J., Inclán D.J., Izquierdo M., Valdez-Mondragón A.

The spider genus Metagonia has been represented on the Galápagos Islands by two blind species inhabiting lava tubes on Isabela and Santa Cruz. Epigean relatives had not been found on Galápagos and were thus thought to be extinct. During a collecting trip in 2019 we found two epigean species and a third blind hypogean species. Here we describe these new species based on males and females, redescribe both previously known species, and add all five species to the recently published molecular phylogeny of Pholcidae, together with more than 30 further congeners from the mainland. Galápagos Metagonia is recovered as a monophyletic group within the South American–Caribbean M. potiguar group. Galápagos Metagonia is divided into an epigean clade and a hypogean clade. Each species is restricted to an individual island (Isabela or Santa Cruz; with one possible exception), suggesting that the epigean Metagonia species are native rather than introduced. ZooBank registration: http://zoobank.org/References/0812B715-8446-4B28-BCE0-6AB504BBEC7E.

Huber B.A., Acurio A.E.

Prigent S.R., Lang M., Nagy O., Acurio A., Matamoro-Vidal A., Courtier-Orgogozo V., David J.R.

Acurio A.E., Rhebergen F.T., Paulus S., Courtier-Orgogozo V., Lang M.

Male genitals have repeatedly evolved left-right asymmetries, and the causes of such evolution remain unclear. The Drosophila nannoptera group contains four species, among which three exhibit left-right asymmetries of distinct genital organs. In the most studied species, Drosophila pachea, males display asymmetric genital lobes and they mate right-sided on top of the female. Copulation position of the other species is unknown. To assess whether the evolution of genital asymmetry could be linked to the evolution of one-sided mating, we examined phallus morphology and copulation position in D. pachea and closely related species. The phallus was found to be symmetric in all investigated species except D. pachea, which displays an asymmetric phallus with a right-sided gonopore, and D. acanthoptera, which harbors an asymmetrically bent phallus. In all examined species, males were found to position themselves symmetrically on top of the female, except in D. pachea and D. nannoptera, where males mated right-sided, in distinctive, species-specific positions. In addition, the copulation duration was found to be increased in the nannoptera group species compared to closely related outgroup species. Our study shows that gains, and possibly losses, of asymmetry in genital morphology and mating position have evolved repeatedly in the nannoptera group. Current data does not allow us to conclude whether genital asymmetry has evolved in response to changes in mating position, or vice versa.

Acurio A., Rhebergen F.T., Paulus S., Courtier-Orgogozo V., Lang M.

AbstractBackgroundMale genitals have repeatedly evolved left-right asymmetries, and the causes of such evolution remain unclear. TheDrosophila nannopteragroup contains four species, among which three exhibit left-right asymmetries of distinct genital organs. In the most studied species,Drosophila pachea, males display asymmetric genital lobes and they mate right-sided on top of the female. Copulation position of the other species is unknown.ResultsTo assess whether the evolution of genital asymmetry could be linked to the evolution of one-sided mating, we examined phallus morphology and copulation position inD. pacheaand closely related species. The phallus was found to be symmetric in all investigated species exceptD. pachea, which display an asymmetric phallus with a right-sided gonopore, andD. acanthoptera, which harbor an asymmetrically bent phallus. In all examined species, males were found to position themselves symmetrically on top of the female, except inD. pacheaandD. nannoptera, where males mated right-sided, in distinctive, species-specific positions. In addition, the copulation duration was found to be increased innannopteragroup species compared to closely related outgroup species.ConclusionOur study shows that gains, and possibly losses, of asymmetry in genital morphology and mating position have evolved repeatedly in thenannopteragroup. Current data does not allow us to conclude whether genital asymmetry has evolved in response to changes in mating position, or vice versa.

Lang M., Polihronakis Richmond M., Acurio A.E., Markow T.A., Orgogozo V.

The Drosophila nannoptera species group, a taxon of Mexican cactophilic flies, is an excellent model system to study the influence of abiotic and biotic factors on speciation, the genetic causes of ecological specialization and the evolution of unusual reproductive characters. However, the phylogenetic relationships in the nannoptera species group and its position within the virilis-repleta phylogeny have not been thoroughly investigated. Using a multilocus data set of gene coding regions of eight nuclear and three mitochondrial genes, we found that the four described nannoptera group species diverged rapidly, with very short internodes between divergence events. Phylogenetic analysis of repleta group lineages revealed that D. inca and D. canalinea are sister to all other repleta group species, whereas the annulimana species D. aracataca and D. pseudotalamancana are sister to the nannoptera and bromeliae species groups. Our divergence time estimates suggest that the nannoptera species group radiated following important geological events in Central America. Our results indicate that a single evolutionary transition to asymmetric genitalia and to unusual sperm storage may have occurred during evolution of the nannoptera group.

Acurio A., Rafael V., Céspedes D., Ruiz A.

Abstract A phylogenetic approach based on morphological characters is the only alternative applicable in cases where molecular data are unavailable. During a taxonomic inventory of Drosophilidae in 12 localities of Ecuador (South America), we discovered a new species of cactophilic spotted-thorax Drosophila Fallen that here we formally describe as Drosophila machalilla Acurio 2013. To classify this new species, we analyzed the terminalia of male and female adults, finding similarities with flies of two neotropical spotted-thorax species groups of Drosophila, namely rep leta and peruensis. Flies or DNA sequence data are unavailable for the latter species group, hindering a molecular approach. Thus, to accurately classify the new species, we carried out a maximum parsimony cladistic analysis using 52 morphological characters from nine representative taxa of virilis, willistoni, repleta, and peruensis species groups. The results indicate that D. machalilla sp. nov. belongs neither to the repleta group nor to the peruensis group and suggest that a new species group should be erected to house D. machalilla and Drosophila atalaia Vilela & Sene (1982, previously considered a member of the peruensis species group).

Acurio A., Rafael V., Dangles O.

There have been few reports of invasions in continental rain forests, especially for exotic animals. This study provides original data concerning the potential of exotic drosophilid species to colonize the Amazonian tropical rain forest. To investigate if the structure of drosophilid assemblages differed in response to anthropogenic disturbance, we performed a taxonomic survey at six sites within the Yasuni National Park in Ecuadorian Amazonia along a disturbance gradient from pristine to clearcut artificial forest. A total of 7425 individuals from 34 species were collected of which seven species were exotic. There was significant variation in the assemblage composition along this disturbance gradient; 31 percent of which was explained by the presence of exotic species, particularly at the most disturbed sites, through nonmetric multidimensional scaling and SIMPER analyses. These results confirm the susceptibility of continental rain forests to invasion by exotic species. There is an urgent need to develop and implement monitoring systems, for example, based on drosophilid assemblage surveys, to detect exotic invasions in continental tropical forests.

Acurio A.E., Rafael V.L.

En el Parque Nacional Yasuní, reconocido como un sector de alto endemismo y biodiversidad, ubicado al noroeste de la Amazonía Ecuatoriana se realizó el inventario taxonómico de la familia Drosophilidae. Para la captura de los individuos se utilizaron trampas con atrayente de banano y solución de levadura de cerveza. La identificación taxonómica se realizó usando caracteres morfológicos y la terminalia de los machos. En total se colectaron 7425 individuos clasificados en 34 especies de los géneros: Drosophila Fallén, 1823, Scaptodrosophila Duda, 1923, Neotanygastrella Duda, 1923 y Zaprionus Coquillett, 1901. Seis de estas especies son nuevos registros para el Ecuador: D. araicas Pavan & Nacrur, 1950, D. equinoxialis Dobzhansky, 1946, D. kikkawai Burla, 1954, D. subsaltans Magalhães, 1956, D. neocordata Magalhães, 1956 y D. peninsularis Patterson & Wheeler, 1942. Estos datos incrementan el número de especies registrados para el país y para la región amazónica.

Bella S., Mouttet R.

AbstractBased on specimens collected in citrus orchards the African fruit fly, Zaprionus tuberculatus Malloch, 1932 (Diptera: Drosophilidae), is recorded for the first time in Corsica (France) and Sicily (Italy). The spread of invasive drosophilid species to new regions via imported fruits occurs very rapidly. In the Mediterranean region, the invasive fly Z. tuberculatus has recently established in numerous areas. Although it is not yet well‐known what impact it may cause on agricultural crops, in the light of recent data it must be considered as potentially harmful, like the closely related species Z. indianus, which has become an economically important pest on fig fruits. The pest status and range expansion of Z. tuberculatus should be assessed to estimate risk to fruit production. This paper provides information on the morphology, distribution and ecology of this drosophilid.

Ramirez P., Martinez Montoya H., Aramayo R., Mateos M.

AbstractSpiroplasma(Class Mollicutes) is a diverse wall-less bacterial genus whose members are strictly dependent on eukaryotic hosts (mostly arthropods and plants), with which they engage in pathogenic to mutualistic interactions.Spiroplasmaare generally fastidious to culturein vitro, especially those that are vertically transmitted by their hosts, which include flies in the genusDrosophila.Drosophilahas been invaded by at least three independent clades ofSpiroplasma: Poulsonii (the best studied; contains reproductive manipulators and defensive mutualists associated two major clades ofDrosophila; and has among the highest substitution rates within bacteria); Citri (restricted to therepletagroup ofDrosophila); and Ixodetis. We report the first genome drafts ofDrosophila-associated Citri CladeSpiroplasma: strainsMoj fromD. mojavensis; strainsAld-Tx fromD. aldrichifrom Texas (newly discovered; also associated withD. mulleri); and strainsHy2 fromD. hydei(the onlyDrosophilaspecies known to naturally also harbor a Poulsonii clade strain, thereby providing an arena for horizontal gene transfer). Compared to their Poulsonii clade counterparts, we infer that the three Citri clade strains have: (1) equal or worse DNA repair abilities; (b) more limited metabolic capacities, which may underlie their comparatively lower titers and transmission efficiency; and (c) similar content of toxin domains, including at least one ribosome inactivating protein (RIP), which are implicated in the Poulsonii-conferred defense against natural enemies. As a byproduct of our phylogenomic analyses and exhaustive search for certain toxin domains in public databases, we document the toxin repertoire in close relatives ofDrosophila-associatedSpiroplasma, and in a very divergent newly discovered lineage (i.e., “clade X”). Phylogenies of toxin-encoding genes or domains imply substantial exchanges between closely and distantly related strains. Surprisingly, despite encoding several toxin genes and achieving relatively high prevalences in certain natural populations (sAld-Tx in this study;sMoj in prior work), fitness assays ofsMoj (this study) andsAld-Tx (prior work) in the context of wasp parasitism fail to detect a beneficial effect to their hosts. Thus, how Citri clade strains persist in theirDrosophilahost populations remains elusive.Data summaryAll novel sequencing data are available through National Center for Biotechnology Information (NCBI) repositories. Illumina raw reads, assemblies, and NCBI annotations are available under BioProject Nos. PRJNA506493 for sHy2, PRJNA506491 for sAld-Tx, and PRJNA355307 for sMoj. Oxford Nanopore (MinIon) reads for sHy2 are under SRA Accession Number SRR12348752.Supporting Material is available under the DOI 10.6084/m9.figshare.c.7437997 or as accompanying supporting documents in the corresponding preprint server or scientific journal.Impact statementSymbiotic associations between arthropods and inherited microbes are pervasive, taxonomically and mechanistically diverse, and strongly influential. Research into the mechanisms and processes governing such heritable interactions is hindered by our inability to culture most inherited symbionts outside of their hosts. We studied three heritable strains ofSpiroplasma(Citri clade) that naturally associate withDrosophilaflies, and that reach relatively high prevalence in certain host populations, but appear to lack traits that would enable them to persist in host populations (e.g. such as high vertical transmission efficiency, reproductive manipulation, or fitness benefits). We compared their genomes to those of a separateSpiroplasmaclade (Poulsonii) that associates withDrosophila, which does exhibit some of the traits that contribute to persistence, including protection against natural enemies of their hosts, and also has among the highest DNA substitution rates recorded for bacteria. Compared to Poulsonii, the three Citri clade strains have smaller genomes and fewer genes, leading us to predict they have similarly high DNA substitution rates, but more limited metabolic capacities, which may explain the comparatively lower densities they achieve within individual hosts, and their frequent loss in lab colonies of their hosts. However, the toxin repertoire of Citri clade was comparatively diverse, and the result of horizontal gene exchange among close and distant strains, and within-genome shuffling. We hypothesize that Citri clade strains persist via unknown fitness benefits conferred to their hosts, possibly mediated by toxins, or by substantial horizontal transmission. Our results, which also capitalized on publicly available assemblies, expand the range ofSpiroplasmalineages that encode a particular combination of toxin types, and revealed the existence of a highly divergent lineage ofSpiroplasmathat associates with insects.

ACURIO A.E.

HUBER B.A., MENG G., GARCÍA J.C., CARVALHO L.S.

The genus Galapa Huber, 2000 includes tiny spiders (body length <1.5 mm) restricted to semi-arid habitats. It has long been thought to be endemic to the Galapagos Islands until G. spiniphila Huber, 2020 was described from the Venezuelan Paraguaná Peninsula. Here, we support this generic assignment with molecular (CO1) data and describe two new species from Colombia (G. gabito Huber sp. n.) and Costa Rica (G. murphyi Huber sp. n.), showing that the genus is actually widely distributed. Distribution modelling identifies several high suitability areas for Galapa, all of which are poorly sampled with respect to Pholcidae (ranging from Nicaragua to northern Peru and Guiana). Our results suggest a strong sampling bias against spiders restricted to dry tropical regions and habitats.  

Huber B.A.

Huber B.A., Meng G., Clark H.L., Cazanove G.

Daddy long-legs spiders are common inhabitants of tropical and subtropical caves around the globe. Numerous species have evolved troglomorphisms, including the loss of body pigments and eyes. Here we describe the first troglomorphic pholcids from Australia and Réunion. Belisana coblynau Huber & Clark, sp. nov. was extracted from mining boreholes in the arid West Australian Pilbara region. It represents a genus that is widespread in tropical forests of South and Southeast Asia, reaching the tropical north and east of Australia. Belisana coblynau is thus presumably a relict whose epigean ancestor lived in the area before the aridification of Australia starting in the early Cenozoic. Buitinga ifrit Huber & Cazanove, sp. nov. was collected in Grotte de La Tortue on Réunion, one of the oldest lava tubes on the island (~300,000 years). Congeneric species are known from East Africa, and the genus does not seem to have reached Madagascar. Since Pholcidae do not balloon, the now extinct epigean ancestor of Buitinga ifrit probably reached the island by highly accidental means (such as rafts or storms).

Salazar-Buenaño F., Guevara D., Barragán A., Carvajal V., Donoso D.A.

This work updates the invertebrate type specimen catalog published by Donoso et al. (2009). The catalog is increased by 2281 type specimens (from 454 species or subspecies) to a total of 4180 type specimens (from 770 species or subspecies) hosted at the Pontificia Universidad Católica del Ecuador and Escuela Politécnica Nacional natural history collections. The new material adds 307 holotypes, 1910 paratypes, and 64 allotypes. It provides original information from four phyla (Arthropoda, Mollusca, Nemata, and Platyhelminthes), eight classes, 21 orders, 73 families, and 156 genera. This updated catalog includes a map showing the type localities in the country, a list of the 71 new type specimens (from 23 species or subspecies) from other countries hosted at both museums, corrections to the previous catalog published by Donoso et al. (2009), and label information from each new specimen.

Yamanouchi H.M., Tanaka R., Kamikouchi A.

Huber B.A., Meng G.

The Pholcidae subfamily Smeringopinae has been revised extensively over the last decade, and most of its currently eight genera can now be placed with some confidence in the phylogeny of the family. A notable exception has been the endemic Seychellois genus Cenemus Saaristo, 2001. Morphologically, the genus is mainly characterized by plesiomorphies, which resulted in weakly supported and unstable positions in previous cladistic analyses. Molecular data have not previously been available. Here we revise the morphology of the type species Cenemus culiculus (Simon, 1898), including first SEM photos, and present the first molecular data for the genus. Morphology and molecules continue to give conflicting results regarding the sister taxon of Cenemus, but our analyses strongly support a position of the genus within the northern group of Smeringopinae (Northern Africa and the Mediterranean to India) rather than in the southern group (Subsahara Africa). This supports the idea that Cenemus is an ancient taxon, dating back to the breakup of Gondwana, between the separation of the Mascarene platform from Madagascar (~85 mya) and its separation from India (~60 mya). In addition, we present first molecular data for the recently established Smeringopinae genus Maghreba Huber, 2022, which is consistently resolved as sister to Crossopriza Simon, 1893; we present molecular evidence for the polyphyly of Holocnemus Simon, 1873, supporting previous morphological evidence; and we present an annotated list of the Pholcidae of the Seychelles, most of which are supposedly recent human introductions.

Poma P., Usca M., Toulkeridis T.

Solid waste management is a subject that still represents enormous challenges worldwide and therefore also in Ecuador. In the current study, we evaluated the environmental impacts generated by the management of solid urban waste (SUW) and the disposal in the an open waste dump of in Loreto, eastern Ecuador, regulated by the local government in order to calculate the level of criticality and subsequently develop management strategies. The methodology applied for the evaluation of environmental Impacts is the Strengths-Weaknesses-Opportunities-Threats (SWOT), which allowed to better understand and to proceed in decisions making processes such as the implementation of measures that minimize environmental hazards as well as the identification of possible alterations of the environment by the actions of the SUW management. Furthermore, administrators and workers were surveyed, different factors were identified and evaluated and each of the parameters were assigned with impact values. Subsequently, we calculated the level of criticality, which may allow the local government to develop corresponding strategies. Among the most significant results has been the breach of current environmental regulations such as burning used tires at open air, and the discharge of leachate to a freshwater body without prior treatment. The application of the SWOT method indicated a lack of performance in the integral management of the SUW. Furthermore, there is the need for a plan for the municipal management of non-hazardous solid and sanitary waste and the absence of a department dedicated to the integral management SUW.

Moyano J., Zamora-Nasca L.B., Caplat P., García-Díaz P., Langdon B., Lambin X., Montti L., Pauchard A., Nuñez M.A.

Biological invasions produce negative impacts worldwide, causing massive economic costs and ecological impacts. Knowing the relationship between invasive species abundance and the magnitude of their impacts (abundance-impact curves) is critical to designing prevention and management strategies that effectively tackle these impacts. However, different measures of abundance may produce different abundance-impact curves. Woody plants are among the most transformative invaders, especially in grassland ecosystems because of the introduction of hitherto absent life forms. In this study, our first goal was to assess the impact of a woody invader, Pinus contorta (hereafter pine), on native grassland productivity and livestock grazing in Patagonia (Argentina), building abundance-impact curves. Our second goal, was to compare different measure of pine abundance (density, basal area and canopy cover) as predictors of pine's impact on grassland productivity. Our third goal, was to compare abundance-impact curves among the mentioned measures of pine abundance and among different measures of impact: total grassland productivity, palatable productivity and sheep stocking rate (the number of sheep that the grassland can sustainably support). Pine canopy cover, closely followed by basal area, was the measure of abundance that best explained the impact on grassland productivity, but the shape of abundance impact curves differed between measures of abundance. While increases in pine density and basal area always reduced grassland productivity, pine canopy cover below 30% slightly increased grassland productivity and higher values caused an exponential decline. This increase in grassland productivity with low levels of pine canopy cover could be explained by the amelioration of stressful abiotic conditions for grassland species. Different measures of impact, namely total productivity, palatable productivity and sheep stocking rate, drew very similar results. Our abundance-impact curves are key to guide the management of invasive pines because a proper assessment of how many invasive individuals (per surface unit) are unacceptable, according to environmental or economic impact thresholds, is fundamental to define when to start management actions.

van Gammeren S., Lang M., Rücklin M., Schilthuizen M.

Background Asymmetric genitalia have repeatedly evolved in animals, yet the underlying causes for their evolution are mostly unknown. The fruit fly Drosophila pachea has asymmetric external genitalia and an asymmetric phallus with a right-sided phallotrema (opening for sperm release). The complex of female and male genitalia is asymmetrically twisted during copulation and males adopt a right-sided copulation posture on top of the female. We wished to investigate if asymmetric male genital morphology and a twisted gentitalia complex may be associated with differential allocation of sperm into female sperm storage organs. Methods We examined the internal complex of female and male reproductive organs by micro-computed tomography and synchrotron X-ray tomography before, during and after copulation. In addition, we monitored sperm aggregation states and timing of sperm transfer during copulation by premature interruption of copulation at different time-points. Results The asymmetric phallus is located at the most caudal end of the female abdomen during copulation. The female reproductive tract, in particular the oviduct, re-arranges during copulation. It is narrow in virgin females and forms a broad vesicle at 20 min after the start of copulation. Sperm transfer into female sperm storage organs (spermathecae) was only in a minority of examined copulation trials (13/64). Also, we found that sperm was mainly transferred early, at 2–4 min after the start of copulation. We did not detect a particular pattern of sperm allocation in the left or right spermathecae. Sperm adopted a granular or filamentous aggregation state in the female uterus and spermathecae, respectively. Discussion No evidence for asymmetric sperm deposition was identified that could be associated with asymmetric genital morphology or twisted complexing of genitalia. Male genital asymmetry may potentially have evolved as a consequence of a complex internal alignment of reproductive organs during copulation in order to optimize low sperm transfer rates.

Gramenos I.A., Soto E.M., Lavagnino N.J.

Zaprionus indianus Gupta (Diptera: Drosophilidae) is a fly species native to the Afrotropical biogeographic region that expanded its geographical distribution to the American continent around 1999. This fly lays eggs, feeds, and develops on a wide variety of fruits colonized by yeasts and bacteria, as well as on ripe, non-damaged soft-skinned fruits. The arrival of Z. indianus to American ecosystems entails co-existence with other drosophilid species with the same resource specificity, such as the cosmopolitan human commensal Drosophila melanogaster Meigen. In this scenario, the oviposition strategy could be relevant for invasion success in terms of partitioning the utilization of resources in space or time. We investigated whether Z. indianus avoids laying eggs in resources previously used by another species (D. melanogaster), or whether oviposition is unaffected by the presence of other species’ larvae. Results show a stable oviposition behavior of Z. indianus, considering that this fly lays the same number of eggs regardless of whether the oviposition resource has larvae of other species, whereas D. melanogaster showed a flexible oviposition behavior when presented with the same oviposition resources. Zaprionus indianus being a good larval competitor against other drosophilids, this stable oviposition strategy could be positive for invasiveness as it ensures a continuous spread of eggs and subsequent larval development during invasion in new and heterogeneous ecosystems.

van Gammeren S., Lang M., Rücklin M., Schilthuizen M.

AbstractBackgroundAsymmetric genitalia have repeatedly evolved in animals, yet the underlying causes for their evolution are mostly unknown. The fruitfly Drosophila pachea has asymmetric external genitalia and an asymmetric phallus with a right-sided gonopore. The complex of female and male genitalia is asymmetrically twisted during copulation and males adopt a right-sided copulation posture on top of the female. We wished to investigate if asymmetric male genital morphology and a twisted gentitalia complex may be associated with differential allocation of sperm into female sperm storage organs.MethodsWe examined the internal complex of female and male reproductive organs by micro-computed tomography using Synchrotron X-rays before, during and after copulation. In additon, we monitored sperm aggregation states and timing of sperm transfer during copulation by premature interruption of copulation at different time-points.ResultsThe asymmetric phallus is located at the most caudal end of the female abdomen during copulation. The female reproductive tract, in particular the oviduct, re-arranges during copulation. It is narrow in virgin females and forms a broad vesicle at 20 min after the start of copulation. Sperm transfer into female sperm storage organs (spermathecae) was only in a minority of examined copulation trials (13 / 64). Also, we found that sperm was mainly transferred early, at 2 - 4 min after the start of copulation. We did not detect a particular pattern of sperm allocation in the left or right spermathecae. Sperm adopted a granular or filamentous aggregation state in the female uterus and spermathecae, respectively.DiscussionNo evidence for asymmetric sperm deposition was identified that could be associated with asymmetric genital morphology or twisted complexing of genitalia. Male genital asymmetry may potentially have evolved as a consequence of a complex internal alignment of reproductive organs during copulation in order to optimize low sperm transfer rates.

Lefèvre B.M., Delvigne M., Vidal J., Courtier-Orgogozo V., Lang M.

AbstractLeft-right asymmetries recurrently evolve in animals but the underlying developmental mechanisms are unknown. In mostDrosophilaspecies, the male genitalia is symmetric and undergoes a clockwise 360° rotation during development. InD. melanogaster, this tissue remodeling process is directed by class I myosins: in MyoID mutants the rotation is reversed and the genitalia remains symmetric. Males ofDrosophila pacheahave evolved unique left-right asymmetric genital organs and a characteristic right-sided copulation posture in the past 3-6 million years. To test if these asymmetries in morphology and behavior evolved via the recruitment of pre-existing directional cues controlled by MyoID, we used CRISPR to knockout MyoID inD. pachea. Strikingly, mutant males undergo a reverse genitalia rotation and develop mirror-image asymmetric genitalia, indicating that MyoID controls both the direction of genitalia rotation direction and morphological asymmetry. Although genital asymmetry is reversed, MyoID mutants still adopt a wild-type right-sided copulation posture. Our results show that MyoID and its asymmetry guidance role were recruited for the evolution of a novel left-right asymmetry inD. pacheaand that lateralized copulation behavior is determined by other mechanisms. The evolution of a new left-right organ size asymmetry inD. pacheainvolved recruitment of existing directional cues.

Etges W.J., Johnson W.R., Duncan G.A., Huckins G., Heed W.B.

Huber B.A.

The genera Holocnemus Simon, 1873 and Crossopriza Simon, 1893 are revised. Together with Stygopholcus Kratochvíl, 1932 (revised recently) and the newly described genus Maghreba gen. nov., they constitute the spotted-leg clade within the northern clade of Smeringopinae. Males and females in this group are characterized by dark marks on the leg femora and tibiae. The native area of the spotted-leg clade ranges from northern Africa and the Mediterranean to Central Asia and NW India. A morphological cladistic analysis suggests that Holocnemus is paraphyletic while Crossopriza is monophyletic, but morphology seems only partly adequate to resolve phylogenetic relationships convincingly. The genus Holocnemus includes four species, all of which are redescribed: H. pluchei (Scopoli, 1763); H. reini (C. Koch, 1873) comb. nov. (transferred from Pholcus); H. caudatus (Dufour, 1820); and H. hispanicus Wiehle, 1933. The genus Maghreba gen. nov. includes eight species from NW Africa: M. aurouxi (Barrientos, 2019) gen. et comb. nov. (transferred from Holocnemus; redescribed, female newly described) and seven newly described species. The genus Crossopriza includes six previously described species (of which five are redescribed), and 18 newly described species. The Madagascan C. nigrescens Millot, 1946 is synonymized with C. lyoni (Blackwall, 1867). All new species are described on the basis of both sexes.

Leclerc C., Magneville C., Bellard C.

Aim Islands are one of the most threatened worldwide biotas. Based on their taxonomic diversity, some insular regions have been identified as key areas of conservation. Recently, systematic conservation planning has advocated for the use of multiple biodiversity facets to protect unique evolutionary and functional processes. Here, we identified priority areas for threatened insular endemic mammals across three key dimensions of biodiversity (taxonomic, phylogenetic, and functional), as well as their protection level and threats affecting them. Location Worldwide. Methods We applied diversity–area relationships to identify insular regions that harbored a disproportionately high rate of threatened endemic mammal diversity (whether taxonomic, phylogenetic, or functional) given their area for 1,799 islands across 19 insular regions. We also assessed the level of protection and the threats affecting biodiversity within each insular region. Results We showed a fairly good congruence between top-ranked insular regions based on taxonomic, phylogenetic, and functional diversity. Specifically, we identified four hotspots for endemic mammalian conservation through the three diversity facets: Indo-Burma, Madagascar and the Indian Ocean Islands, Mesoamerica and Galápagos Islands, and Wallacea. Except for Mesoamerica and Galápagos Islands, the protected areas coverage is low (

Srivathsan A., Lee L., Katoh K., Hartop E., Kutty S.N., Wong J., Yeo D., Meier R.

DNA barcodes are a useful tool for discovering, understanding, and monitoring biodiversity which are critical tasks at a time of rapid biodiversity loss. However, widespread adoption of barcodes requires cost-effective and simple barcoding methods. We here present a workflow that satisfies these conditions. It was developed via “innovation through subtraction” and thus requires minimal lab equipment, can be learned within days, reduces the barcode sequencing cost to < 10 cents, and allows fast turnaround from specimen to sequence by using the portable MinION sequencer. We describe how tagged amplicons can be obtained and sequenced with the real-time MinION sequencer in many settings (field stations, biodiversity labs, citizen science labs, schools). We also provide amplicon coverage recommendations that are based on several runs of the latest generation of MinION flow cells (“R10.3”) which suggest that each run can generate barcodes for > 10,000 specimens. Next, we present a novel software, ONTbarcoder, which overcomes the bioinformatics challenges posed by MinION reads. The software is compatible with Windows 10, Macintosh, and Linux, has a graphical user interface (GUI), and can generate thousands of barcodes on a standard laptop within hours based on only two input files (FASTQ, demultiplexing file). We document that MinION barcodes are virtually identical to Sanger and Illumina barcodes for the same specimens (> 99.99%) and provide evidence that MinION flow cells and reads have improved rapidly since 2018. We propose that barcoding with MinION is the way forward for government agencies, universities, museums, and schools because it combines low consumable and capital cost with scalability. Small projects can use the flow cell dongle (“Flongle”) while large projects can rely on MinION flow cells that can be stopped and re-used after collecting sufficient data for a given project.

Stefanini M.I., Gottschalk M.S., Calvo N.S., Soto I.M.

The Drosophila repleta group comprises more than one hundred species that inhabit several environments in the Neotropics and use different hosts as rearing and feeding resources. Rather homogeneous in their external morphology, they are generally distinguished by the male genitalia, seemingly their fastest evolving morphological trait, constituting an excellent model to study patterns of genital evolution in the context of a continental adaptive radiation. Although much is known about the evolution of animal genitalia at population level, surveys on macroevolutionary scale of this phenomenon are scarce. This study used a suite of phylogenetic comparative methods to elucidate the macroevolutionary patterns of genital evolution through deep time and large continental scales. Our results indicate that male genital size and some aspects of shape have been evolving by speciational evolution, probably due to the microevolutionary processes involved in species mate recognition. In contrast, several features of the aedeagus shape seemed to have evolved in a gradual fashion, with heterogeneous evolutionary phenotypic rates among clades. In general, the tempo of the evolution of aedeagus morphology was constant from the origin of the group until the Pliocene, when it accelerated in some clades that diversified mainly in this period. The incidence of novel ecological conditions in the tempo of aedeagus evolution and the relationship between species mate recognition and speciation in the Drosophila repleta group are discussed.

Huber B.A., Pavlek M., Komnenov M.

The genus Stygopholcus Kratochvíl, 1932 is endemic to the Balkan Peninsula and includes only four nominal species: the epigean S. photophilus Senglet, 1971 in the south (Greece to Albania) and the ‘northern clade’ consisting of three troglophile species ranging from Croatia to Albania: S. absoloni (Kulczyński, 1914); S. skotophilus Kratochvíl, 1940; and S. montenegrinus Kratochvíl, 1940 (original rank re-established). We present redescriptions of all species, including extensive data on ultrastructure, linear morphometrics of large samples, and numerous new localities. We georeference previously published localities as far as possible, correct several published misidentifications, and clarify nomenclatorial problems regarding the authority of Stygopholcus and the identity of the type species S. absoloni. We suggest that the ‘northern clade’ has a relict distribution, resulting from past and present geologic and climatic factors. Future work on Stygopholcus should focus on the southern Dinarides, combining dense sampling with massive use of molecular data.

HUBER B.A.

The genus Artema Walckenaer, 1837 includes some of the largest pholcid spiders and is geographically largely restricted to Central Asia, the Middle East, the Arabian Peninsula, and the eastern Mediterranean. One species has previously been known from West Africa. The first known Moroccan species, A. martensi sp. n., extends the known distribution of the genus to the northwestern limit of the African continent. The species is described from two caves in the western Anti-Atlas, but it is not troglomorphic. A comparative analysis of male carapace width in 1632 pholcid species shows that A. martensi sp. n. is the largest known pholcid with respect to this character. Plots of mean carapace sizes of newly described species on periods of time (50 years, 20 years) show that the mean sizes of newly described species have been constantly decreasing. 

Letunic I., Bork P.

Abstract The Interactive Tree Of Life (https://itol.embl.de) is an online tool for the display, manipulation and annotation of phylogenetic and other trees. It is freely available and open to everyone. iTOL version 5 introduces a completely new tree display engine, together with numerous new features. For example, a new dataset type has been added (MEME motifs), while annotation options have been expanded for several existing ones. Node metadata display options have been extended and now also support non-numerical categorical values, as well as multiple values per node. Direct manual annotation is now available, providing a set of basic drawing and labeling tools, allowing users to draw shapes, labels and other features by hand directly onto the trees. Support for tree and dataset scales has been extended, providing fine control over line and label styles. Unrooted tree displays can now use the equal-daylight algorithm, proving a much greater display clarity. The user account system has been streamlined and expanded with new navigation options and currently handles >1 million trees from >70 000 individual users.

Gentili R., Schaffner U., Martinoli A., Citterio S.

As far back as the 18th century, many naturalists including Augustin Pyramus De Candolle and Charles Darwin, observed the phenomenon of non-native species. These were defined as ‘species outside of...

Heads M., Grehan J.R.

In the traditional biogeographic model, the Galápagos Islands appeared a few million years ago in a sea where no other islands existed and were colonized from areas outside the region. However, recent work has shown that the Galápagos hotspot is 139 million years old (Early Cretaceous), and so groups are likely to have survived at the hotspot by dispersal of populations onto new islands from older ones. This process of metapopulation dynamics means that species can persist indefinitely in an oceanic region, as long as new islands are being produced. Metapopulations can also undergo vicariance into two metapopulations, for example at active island arcs that are rifted by transform faults. We reviewed the geographic relationships of Galápagos groups and found 10 biogeographic patterns that are shared by at least two groups. Each of the patterns coincides spatially with a major tectonic structure; these structures include: the East Pacific Rise; west Pacific and American subduction zones; large igneous plateaus in the Pacific; Alisitos terrane (Baja California), Guerrero terrane (western Mexico); rifting of North and South America; formation of the Caribbean Plateau by the Galápagos hotspot, and its eastward movement; accretion of Galápagos hotspot tracks; Andean uplift; and displacement on the Romeral fault system. All these geological features were active in the Cretaceous, suggesting that geological change at that time caused vicariance in widespread ancestors. The present distributions are explicable if ancestors survived as metapopulations occupying both the Galápagos hotspot and other regions before differentiating, more or less in situ.

Cayot L.J., Campbell K., Carrión V.

The flora and fauna of oceanic islands are extremely vulnerable to invasive introduced species. Galapagos giant tortoise species, many critically endangered due to overexploitation by whalers and others, have been negatively impacted by several invasive species over the last two centuries. This chapter reviews the introduced species that impact giant tortoises: their arrival, establishment, and impacts on tortoises and their habitats, and targeted control, eradication, and conservation efforts of the last 60 years. The species reviews are followed by summaries of three major eradication projects aimed at the restoration of island ecosystems and the giant tortoises that inhabit them.

Yang C., Zheng Y., Tan S., Meng G., Rao W., Yang C., Bourne D.G., O’Brien P.A., Xu J., Liao S., Chen A., Chen X., Jia X., Zhang A., Liu S.

Over the last decade, the rapid development of high-throughput sequencing platforms has accelerated species description and assisted morphological classification through DNA barcoding. However, the current high-throughput DNA barcoding methods cannot obtain full-length barcode sequences due to read length limitations (e.g. a maximum read length of 300 bp for the Illumina’s MiSeq system), or are hindered by a relatively high cost or low sequencing output (e.g. a maximum number of eight million reads per cell for the PacBio’s SEQUEL II system). Pooled cytochrome c oxidase subunit I (COI) barcodes from individual specimens were sequenced on the MGISEQ-2000 platform using the single-end 400 bp (SE400) module. We present a bioinformatic pipeline, HIFI-SE, that takes reads generated from the 5′ and 3′ ends of the COI barcode region and assembles them into full-length barcodes. HIFI-SE is written in Python and includes four function modules of filter, assign, assembly and taxonomy. We applied the HIFI-SE to a set of 845 samples (30 marine invertebrates, 815 insects) and delivered a total of 747 fully assembled COI barcodes as well as 70 Wolbachia and fungi symbionts. Compared to their corresponding Sanger sequences (72 sequences available), nearly all samples (71/72) were correctly and accurately assembled, including 46 samples that had a similarity score of 100% and 25 of ca. 99%. The HIFI-SE pipeline represents an efficient way to produce standard full-length barcodes, while the reasonable cost and high sensitivity of our method can contribute considerably more DNA barcodes under the same budget. Our method thereby advances DNA-based species identification from diverse ecosystems and increases the number of relevant applications.

Steenwyk J.L., Buida T.J., Li Y., Shen X., Rokas A.

Highly divergent sites in multiple sequence alignments (MSAs), which can stem from erroneous inference of homology and saturation of substitutions, are thought to negatively impact phylogenetic inference. Thus, several different trimming strategies have been developed for identifying and removing these sites prior to phylogenetic inference. However, a recent study reported that doing so can worsen inference, underscoring the need for alternative alignment trimming strategies. Here, we introduce ClipKIT, an alignment trimming software that, rather than identifying and removing putatively phylogenetically uninformative sites, instead aims to identify and retain parsimony-informative sites, which are known to be phylogenetically informative. To test the efficacy of ClipKIT, we examined the accuracy and support of phylogenies inferred from 14 different alignment trimming strategies, including those implemented in ClipKIT, across nearly 140,000 alignments from a broad sampling of evolutionary histories. Phylogenies inferred from ClipKIT-trimmed alignments are accurate, robust, and time saving. Furthermore, ClipKIT consistently outperformed other trimming methods across diverse datasets, suggesting that strategies based on identifying and retaining parsimony-informative sites provide a robust framework for alignment trimming.

Huber B.A., Villarreal O.

We present a comprehensive revision of the pholcid spider collection of M.A. González-Sponga, who between 1998 and 2011 described 22 new genera and 51 new species of Pholcidae from Venezuela. In addition, we treat the pholcid material collected during three expeditions to Venezuela conducted between 2002 and 2020. Of González-Sponga’s pholcid taxa we recognize three genera and 24 species as valid. We describe 43 new species (all from males and females) in one new and 13 previously described genera; four genera are newly recorded for Venezuela. We describe the previously unknown females of 15 species, present new records for 46 previously described species, synonymize one genus and one species, and correct numerous minor errors in previous publications on Venezuelan pholcids. At the generic level, the Venezuelan pholcid fauna now appears fairly well known, but available data on distribution and endemism suggest that many species remain undiscovered and undescribed. Despite the obvious gaps, our data are congruent with previous studies on other taxa that have the highest levels of endemism in the Venezuelan Andes, the Coastal Ranges, and the Guyana Highlands. The Falcón Region in particular shows a complex mosaic of biogeographic relationships with other regions. We provide new biological data on numerous species. We document the first cases of evolutionary microhabitat shifts in the genera Mecolaesthus Simon, 1893 and Priscula Simon, 1893. We document several cases of close congeners sharing localities, usually in slightly to conspicuously different microhabitats, sometimes apparently in identical microhabitats. We document several cases of color polymorphism, mostly intersexual, in Metagonia conica (Simon, 1893) both intersexual and among males. We document further cases of two rare phenomena in Pholcidae: use of specific non-silken structures for retreats (in Pisaboa Huber, 2000) and egg parasitism (in Priscula).

Parent C.E., Peck S.B., Causton C.E., Roque-Albelo L., Lester P.J., Bulgarella M.

Abstract The yellow paper wasp, Polistes versicolor (Olivier) was first recorded in the Galapagos archipelago in 1988. Its life cycle and ecological impacts were studied on two islands 11 yr after it was first discovered. This invasive wasp adapted quickly and was found in most environments. Colony counts and adult wasp monitoring showed a strong preference for drier habitats. Nest activities were seasonally synchronized, nest building followed the rains in the hot season (typically January–May), when insect prey increases, and peaked as temperature and rains started to decline. Next, the number of adult wasps peaked during the cool season when there is barely any rain in the drier zones. In Galapagos, almost half of the prey loads of P. versicolor were lepidopteran larvae, but wasps also carried spiders, beetles, and flies back to the colonies. An estimated average of 329 mg of fresh insect prey was consumed per day for an average colony of 120–150 wasp larvae. The wasps preyed upon native and introduced insects, but likely also affect insectivorous vertebrates as competitors for food. Wasps may also compete with native pollinators as they regularly visited flowers to collect nectar, and have been recorded visiting at least 93 plant species in Galapagos, including 66 endemic and native plants. Colonies were attacked by a predatory moth, Taygete sphecophila (Meyrick) (Lepidoptera: Autostichidae), but colony development was not arrested. High wasp numbers also affect the activities of residents and tourists. A management program for this invasive species in the archipelago is essential.