What DNA barcodes reveal: microhabitat preference, hunting strategy and dispersal ability drive genetic variation across Iberian spider species

With almost 40 000 species, the spiders provide important model systems for studies of sociality, mating systems, and sexual dimorphism. However, work on this group is regularly constrained by difficulties in species identification. DNA-based identification systems represent a promising approach to resolve this taxonomic impediment, but their efficacy has only been tested in a few groups. In this study, we demonstrate that sequence diversity in a standard segment of the mitochondrial gene coding for cytochrome c oxidase I (COI) is highly effective in discriminating spider species. A COI profile containing 168 spider species and 35 other arachnid species correctly assigned 100% of subsequently analyzed specimens to the appropriate species. In addition, we found no overlap between mean nucleotide divergences at the intra- and inter-specific levels. Our results establish the potential of COI as a rapid and accurate identification tool for biodiversity surveys of spiders.

Download Full-text

Contrasting Phylogeographic Patterns in Lumnitzera Mangroves Across the Indo-West Pacific

Frontiers in Plant Science ◽

10.3389/fpls.2021.637009 ◽

2021 ◽

Vol 12 ◽

Author(s):

Wuxia Guo ◽

Achyut Kumar Banerjee ◽

Haidan Wu ◽

Wei Lun Ng ◽

Hui Feng ◽

...

Keyword(s):

Genetic Variation ◽

Divergence Time ◽

Circulation Pattern ◽

Dispersal Ability ◽

Oceanic Circulation ◽

Sea Level Changes ◽

Mangrove Species ◽

West Pacific ◽

Divergence Time Estimates ◽

Genetic Break

Mangroves are ecologically important forest communities in tropical and subtropical coasts, the effective management of which requires understanding of their phylogeographic patterns. However, these patterns often vary among different species, even among ecologically similar taxa or congeneric species. Here, we investigated the levels and patterns of genetic variation within Lumnitzera consisting of two species (L. racemosa and L. littorea) with nearly sympatric ranges across the Indo-West Pacific (IWP) region by sequencing three chloroplast DNA regions (for both species) and genotyping 11 nuclear microsatellite loci (for L. littorea). Consistent with findings in studies on other mangrove species, we found that both L. racemosa and L. littorea showed relatively high genetic variation among populations but low genetic variation within populations. Haplotype network and genetic clustering analyses indicated two well-differentiated clades in both L. racemosa and L. littorea. The relationship between geographic and genetic distances and divergence time estimates of the haplotypes indicated that limited dispersal ability of the propagules, emergence of land barriers during ancient sea-level changes, and contemporary oceanic circulation pattern in the IWP influenced the current population structure of the two species. However, the position of genetic break was found to vary between the two species: in L. racemosa, strong divergence was observed between populations from the Indian Ocean and the Pacific Ocean possibly due to land barrier effect of the Malay Peninsula; in L. littorea, the phylogeographic pattern was created by a more eastward genetic break along the biogeographic barrier identified as the Huxley’s line. Overall, our findings strongly supported previous hypothesis of mangrove species divergence and revealed that the two Lumnitzera species have different phylogeographic patterns despite their close genetic relationship and similar current geographic distribution. The findings also provided references for the management of Lumnitzera mangroves, especially for the threatened L. littorea.

Download Full-text

Genetic differentiation over a small spatial scale in the smooth newt (Lissotriton vulgaris)

Herpetological Journal ◽

10.33256/31.2.6169 ◽

2021 ◽

pp. 61-69

Author(s):

Zoltan Toth

Keyword(s):

Genetic Variation ◽

Spatial Scale ◽

Population Biology ◽

Breeding Habitat ◽

Dispersal Ability ◽

Small Spatial Scale ◽

Genetic Population ◽

Lissotriton Vulgaris ◽

Natural Breeding ◽

Allelic Differentiation

Understanding the distribution of genetic variation is central for both population biology and conservation genetics. Genetic population structure can be primarily affected by the species’ dispersal ability, which is assumed to be limited in many amphibians. In this study, we estimated allelic differentiation metrics and FST indices to investigate genetic variation among natural breeding ponds of smooth newts (Lissotriton vulgaris) over a small spatial scale. Based on six microsatellite loci, we found a small, but significant allelic differentiation among clusters of natural breeding ponds (i.e. ‘local regions’), which result was in line with the calculation of corresponding hierarchical FST values. Analysis of molecular variance also indicated significant between-region variation in the study area. Pairwise estimations showed that only the furthermost regions differed from each other in both differentiation measures, but this difference was not attributable to geographic distances between ponds. Our results provide evidence that hierarchical genetic structure can be characteristic to breeding ponds of smooth newts on a small spatial scale in their natural breeding habitat, but dispersal distance may be less limited than previously thought in these philopatric caudates.

Download Full-text

A database of functional traits for spiders from native forests of the Iberian Peninsula and Macaronesia

Biodiversity Data Journal ◽

10.3897/bdj.8.e49159 ◽

2020 ◽

Vol 8 ◽

Author(s):

Nuria Macías-Hernández ◽

Cândida Ramos ◽

Marc Domènech ◽

Sara Febles ◽

Irene Santos ◽

...

Keyword(s):

Iberian Peninsula ◽

Morphological Traits ◽

Functional Trait ◽

Foraging Strategy ◽

Dispersal Ability ◽

Trophic Specialization ◽

Spider Species ◽

Individual Level ◽

Direct Measurements ◽

Total Body

There is an increasing demand for databases including species trait information for biodiversity and community ecology studies. The existence of trait databases is useful for comparative studies within taxa or geographical regions, but there is low availability of databases for certain organisms. Here we present an open access functional trait database for spiders from Macaronesia and the Iberian Peninsula, recording several morphological and ecological traits related to the species life histories, microhabitat and trophic preferences. We present a database that includes 12 biological traits for 506 spider species present in natural forests of the Iberian Peninsula (Spain) and three Macaronesian archipelagoes (Azores, Madeira and Canary Islands). The functional trait database consists of two sections: individual-level data for six morphological traits (total body size, prosoma length, prosoma width, prosoma height, tibia I length and fang length), based on direct measurements of 2844 specimens of all spider species; and species-level aggregate data for 12 traits (same 6 morphological traits as in the previous section plus dispersal ability, vertical stratification, circadian activity, foraging strategy, trophic specialization and colonization status), based on either the average of the direct measurements or bibliographic searches. individual-level data for six morphological traits (total body size, prosoma length, prosoma width, prosoma height, tibia I length and fang length), based on direct measurements of 2844 specimens of all spider species; and species-level aggregate data for 12 traits (same 6 morphological traits as in the previous section plus dispersal ability, vertical stratification, circadian activity, foraging strategy, trophic specialization and colonization status), based on either the average of the direct measurements or bibliographic searches. This functional trait database will serve as a data standard for currently ongoing analyses that require trait and functional diversity statistics.

Download Full-text

Importance of body size and hunting strategy during interactions between the Mexican red-rump tarantula (Brachypelma vagans) and the wolf spider Lycosa subfusca

Canadian Journal of Zoology ◽

10.1139/cjz-2012-0308 ◽

2013 ◽

Vol 91 (8) ◽

pp. 545-553 ◽

Cited By ~ 7

Author(s):

A. Dor ◽

Y. Hénaut

Keyword(s):

Life History ◽

Wolf Spider ◽

Life Stages ◽

Wolf Spiders ◽

Predatory Behaviour ◽

Spider Species ◽

Behavioural Adaptation ◽

Brachypelma Vagans ◽

The Relationship ◽

Hunting Strategy

Behavioural adaptation helps animals to maximize their ability to obtain food and to avoid being eaten, increasing fitness. To achieve this, they must assess predation risk and evaluate foraging needs simultaneously. In two sympatric spider species, the wandering wolf spider Lycosa subfusca F.O.P. Cambridge, 1902 and the sit-and-wait Mexican red-rump tarantula (Brachypelma vagans Ausserer, 1875), we studied the relationship between predatory behaviour and antipredatory behaviour at different life stages. In the laboratory, encounters were organized between one wolf spider (small, medium-sized, or large) and one tarantula (spiderling, small, medium-sized, or large). Attack latencies and behaviours were recorded. The results showed that wolf spiders attacked and successfully captured younger tarantulas, while they avoided or retreated from older ones. Tarantulas preferentially attacked and captured older wolf spiders. On other hand, younger wolf spiders were more cautious than older ones, which waited until for the tarantulas to attack before retreating. Younger tarantulas were also more cautious than adults, which never retreated from attack and increased their success in attacks with age. Finally, we discuss the relationship between the predatory strategies of both spiders with their perception abilities and life history.

Download Full-text

Genetic variation and genetic structure within metapopulations of two closely related selfing and outcrossing Zingiber species (Zingiberaceae)

AoB Plants ◽

10.1093/aobpla/plaa065 ◽

2020 ◽

Author(s):

Rong Huang ◽

Zong-Dian Zhang ◽

Yu Wang ◽

Ying-Qiang Wang

Keyword(s):

Genetic Diversity ◽

Genetic Variation ◽

Genetic Structure ◽

Habitat Fragmentation ◽

Spatial Genetic Structure ◽

Full Range ◽

Breeding Systems ◽

Dispersal Ability ◽

Phylogenetic Distance ◽

Plant Populations

Abstract Habitat fragmentation strongly affects the genetic diversity of plant populations, and this has always attracted much research interest. Although numerous studies have investigated the effects of habitat fragmentation on the genetic diversity of plant populations, fewer studies have compared species with contrasting breeding systems while accounting for phylogenetic distance. Here, we compare the levels of genetic diversity and differentiation within and among subpopulations in metapopulations (at fine-scale level) of two closely related Zingiber species, selfing Zingiber corallinum and outcrossing Zingiber nudicarpum. Comparisons of the genetic structure of species from unrelated taxa may be confounded by the effects of correlated ecological traits or/and phylogeny. Thus, we possibly reveal the differences in genetic diversity and spatial distribution of genetic variation within metapopulations that relate to mating systems. Compared to outcrossing Z. nudicarpum, the subpopulation genetic diversity in selfing Z. corallinum was significantly lower, but the metapopulation genetic diversity was not different. Most genetic variation resided among subpopulations in selfing Z. corallinum metapopulations, while a significant portion of variation resided either within or among subpopulations in outcrossing Z. nudicarpum, depending on whether the degree of subpopulation isolation surpass the dispersal ability of pollen and seed. A stronger spatial genetic structure appeared within subpopulations of selfing Z. corallinum potentially due to restricted pollen flow and seed dispersal. In contrast, a weaker genetic structure was apparent in subpopulations of outcrossing Z. nudicarpum most likely caused by extensive pollen movement. Our study shows that high genetic variation can be maintained within metapopulations of selfing Zingiber species, due to increased genetic differentiation intensified primarily by the stochastic force of genetic drift among subpopulations. Therefore, maintenance of natural variability among subpopulations in fragmented areas is key to conserve the full range of genetic diversity of selfing Zingiber species. For outcrossing Zingiber species, maintenance of large populations is an important factor to enhance genetic diversity.

Download Full-text

Exponential distribution of velocities and power distribution of quiescent periods in the spontaneous movement patterns of three hunting spiders

Biological Journal of the Linnean Society ◽

10.1093/biolinnean/blab020 ◽

2021 ◽

Author(s):

Erik Baatrup ◽

Anders O Rasmussen ◽

Hans Malte ◽

Søren Toft

Keyword(s):

Power Distribution ◽

Single Cells ◽

Logarithmic Scale ◽

Spontaneous Movement ◽

Decay Function ◽

Spider Species ◽

Hunting Strategies ◽

General Rules ◽

Locomotor Patterns ◽

Hunting Strategy

Abstract Here, we investigate the spontaneous locomotor patterns in three spiders with different hunting strategies. The locomotor activity of adult wolf spiders Pardosa amentata, with a sit-and-move hunting strategy, has previously been demonstrated to follow strictly mathematical rules, with most time spent at lower velocities and exponentially decreasing time spent at increasing velocities. Likewise, they have an abundance of short quiescent (resting) periods following a power decay function towards longer quiescent periods. In the present study, we explored whether similar distributions were expressed in juveniles of P. amentata and in two other spider species with different hunting strategies: the sit-and-wait spider Xysticus cristatus and the actively searching sac spider Clubiona phragmitis. We found that all three spider species followed the same two general rules of movement. However, there were differences among the three species. On a logarithmic scale of exponential velocities and a double-logarithmic scale of the rest power decay function, the slopes of the lines for the three species differed. We propose that these differences reflect the behavioural and locomotor differences of the three hunting strategies. Furthermore, we compare our results with similar movement distributions in single cells, fruit flies, mice and even humans.

Download Full-text

High genetic diversity and presence of genetic structure characterise the Corso-Sardinian endemics Ruta corsica and Ruta lamarmorae (Rutaceae)

10.1101/337931 ◽

2018 ◽

Author(s):

Marilena Meloni ◽

Caterina Angela Dettori ◽

Andrea Reid ◽

Gianluigi Bacchetta ◽

Laetitia Hugot ◽

...

Keyword(s):

Genetic Variation ◽

Genetic Structure ◽

Biological Diversity ◽

Taxonomic Status ◽

Single Species ◽

Dispersal Ability ◽

Separate Species ◽

High Genetic Diversity ◽

History Of

SummaryCorsica and Sardinia form one of the ten areas with highest biodiversity in the Mediterranean and are considered one of the priority regions for conservation in Europe. In order to preserve the high levels of endemism and biological diversity at different hierarchical levels, knowledge of the evolutionary history and current genetic structure of Corso-Sardinian endemics is instrumental. Microsatellite markers were newly developed and used to study the genetic structure and taxonomic status of Ruta corsica and Ruta lamarmorae, rare endemics of Corsica and Sardinia, respectively, and previously considered a single species. Our analyses identified high levels of genetic variation within each species (P=0.883, He=0.543 for R. corsica; P=0.972, He=0.627 for R. lamarmorae). Intrinsic traits of the species (hermaphroditism, proterandry and polyploidy) and island-dependent factors (i.e. age, origin and history of the islands) might explain the detected high levels of genetic variation. We discovered differentiation between R. corsica and R. lamarmorae, and genetic structure within each species, which are consistent with the observation of low dispersal ability for both species. Our genetic results support the recent taxonomic classification of R. corsica and R. lamarmorae as separate species and suggest that they diverge at only few loci. One R. corsica population (SA) strongly differed from all other studied populations and appeared to be the product of hybridization between the two species in STRUCTURE analyses. Our results provide important insights for the conservation of the two rare endemics. Further genetic analyses are recommended for R. lamarmorae and for population SA (R. corsica).

Download Full-text

Fine-scale interactions between habitat quality and genetic variation suggest an impact of grazing on the critically endangered Crau Plain grasshopper (Pamphagidae: Prionotropis rhodanica)

Journal of Orthoptera Research ◽

10.3897/jor.27.15036 ◽

2018 ◽

Vol 27 (1) ◽

pp. 61-73 ◽

Cited By ~ 2

Author(s):

Sylvain Piry ◽

Karine Berthier ◽

Réjane Streiff ◽

Sandrine Cros-Arteil ◽

Laurent Tatin ◽

...

Keyword(s):

Genetic Variation ◽

Population Density ◽

Habitat Quality ◽

Spatial Genetic Structure ◽

Spatial Scales ◽

Critically Endangered ◽

Dispersal Ability ◽

Small Scale ◽

Fine Scale ◽

Grasshopper Species

The Crau Plain grasshopper, Prionotropisrhodanica Uvarov, 1923 (Orthoptera: Pamphagidae: Thrinchinae), is a rare grasshopper species endemic to the Crau Plain, a steppic habitat in France with unique floristic and faunistic communities. During recent decades, the area covered by these steppic grasslands has been highly reduced and fragmented due to the development of irrigation-based agriculture, roads, as well as industrial and military complexes. The restricted distribution, low population density and poor dispersal ability of P.rhodanica, combined with the destruction of its habitat, has led to the classification of this species as critically endangered in the IUCN Red List of Threatened Species. Decreases in habitat quality due to intensive grazing in the remnant grassland patches constitute an additional threat for P.rhodanica that can impact population dynamics at a relatively small-scale. In this work, we focused on a small area of about 3 km2 occupied by one of the largest subpopulations observed in 2000–2001. We conducted a single-time snapshot intensive survey of grasshopper density and genetic variation at 11 microsatellite markers. We used a recent method, MAPI, to visualize the spatial genetic structure as a continuous surface and to determine, with the simultaneous use of spatial cross-correlograms, whether the normalized difference vegetation index, which informs on the balance between vegetation productivity and grazing intensity, can explain grasshopper population structure at such a fine scale. We found that both population density and gene flow were strongly and positively correlated to habitat quality (higher productivity of grasslands and/or lower sheep grazing). The spatial scales of interaction between these variables were estimated to be highly similar, in the range of 812–880 meters. This result suggests that P.rhodanica is very sensitive to the quality of the grasslands it inhabits.

Download Full-text