- Research article
- Open Access
Spiders (Araneae) of Churchill, Manitoba: DNA barcodes and morphology reveal high species diversity and new Canadian records
BMC Ecology volume 13, Article number: 44 (2013)
Arctic ecosystems, especially those near transition zones, are expected to be strongly impacted by climate change. Because it is positioned on the ecotone between tundra and boreal forest, the Churchill area is a strategic locality for the analysis of shifts in faunal composition. This fact has motivated the effort to develop a comprehensive biodiversity inventory for the Churchill region by coupling DNA barcoding with morphological studies. The present study represents one element of this effort; it focuses on analysis of the spider fauna at Churchill.
198 species were detected among 2704 spiders analyzed, tripling the count for the Churchill region. Estimates of overall diversity suggest that another 10–20 species await detection. Most species displayed little intraspecific sequence variation (maximum <1%) in the barcode region of the cytochrome c oxidase subunit I (COI) gene, but four species showed considerably higher values (maximum = 4.1-6.2%), suggesting cryptic species. All recognized species possessed a distinct haplotype array at COI with nearest-neighbour interspecific distances averaging 8.57%. Three species new to Canada were detected: Robertus lyrifer (Theridiidae), Baryphyma trifrons (Linyphiidae), and Satilatlas monticola (Linyphiidae). The first two species may represent human-mediated introductions linked to the port in Churchill, but the other species represents a range extension from the USA. The first description of the female of S. monticola was also presented. As well, one probable new species of Alopecosa (Lycosidae) was recognized.
This study provides the first comprehensive DNA barcode reference library for the spider fauna of any region. Few cryptic species of spiders were detected, a result contrasting with the prevalence of undescribed species in several other terrestrial arthropod groups at Churchill. Because most (97.5%) sequence clusters at COI corresponded with a named taxon, DNA barcoding reliably identifies spiders in the Churchill fauna. The capacity of DNA barcoding to enable the identification of otherwise taxonomically ambiguous specimens (juveniles, females) also represents a major advance for future monitoring efforts on this group.
Arctic ecosystems, especially those positioned on transition zones, are recognized as areas where the impacts of climate change will be observed first. Despite this fact, the baseline knowledge of species composition needed to monitor biodiversity change is limited for most animal groups. Because it sits at the juncture of three ecoregions, and possesses a strong research infrastructure, Churchill provides a strategic setting for a long-term monitoring program in the Canadian arctic. As a result, it was selected as a site to demonstrate how a comprehensive DNA barcode reference library can both extend understanding of current biodiversity and facilitate future biomonitoring programs. Recent studies of several arthropod groups at Churchill, coupling morphological and DNA barcode analysis, have revealed unexpectedly high diversity and many undescribed species[2–10]. These results have reinforced the need for additional molecular work on the fauna of this region. The present study responds to this need for a key group of invertebrate predators—spiders.
Spiders (Araneae) are a diverse order of arthropods with more than 44,000 described species. Because of their importance as predators in many terrestrial settings, they have the potential to reveal subtle changes in environmental variables[12–14]. Early work in the Churchill region indicated that spiders were one of the most abundant terrestrial arthropod groups, but little information has been available on their diversity. The first study of its fauna indicated the presence of 31 taxa, but just 19 were identified to a species level. Two linyphiids, Pytyohyphantes subarcticus and Wabasso quaestio, were subsequently described from Churchill. Information on the local spider fauna was also extended through taxonomic studies on particular genera[18–20] and a faunal study for Manitoba. Although 483 spiders are known from this province, just 64 of these species have been reported from the Churchill area.
This study provides a DNA barcode reference library for the spiders of Churchill, based upon six years of collection activity. It additionally investigates how well the morphological species concept in spiders corresponds with sequence clusters in the DNA barcode region of the cytochrome c oxidase subunit I (COI) mitochondrial gene[21, 22]. The results indicate the presence of 198 species of spiders at Churchill, and establish the close correspondence between sequence clusters at COI and described species. This latter result indicates that DNA barcoding is a very effective identification tool for the spider assemblage at this locality. This study also extends progress toward a comprehensive DNA barcode reference library for the biota of the Churchill region[2–10, 23], an effort which is creating new opportunities for ecological research and monitoring programs.
Collection of spiders
Spiders were collected during the snow-free months over a six-year interval from a wide range of habitats near Churchill using varied methods (Figure 1). These efforts resulted in the collection of 410 specimens from July 1-August 5, 2005; 517 from August 5-Sept 6, 2006; 548 from June 8-August 21, 2007; 32 from May 30-November 3, 2008; 1411 from July 17-August 15, 2009; and 547 from June 30-August 25, 2010. Most specimens were obtained through general collecting efforts by field course students and summer researcher assistants, but GAB carried out targeted sampling of spiders from July 17-August 2, 2009.
Collections were primarily made along Goose Creek Road, Cape Merry, Launch Road, Churchill Northern Studies Centre, and Twin Lakes (Figure 1). These collections (3465 specimens) were augmented with a small sample (41 specimens) from Wapusk National Park, Manitoba, producing a total of 3506 specimens. Collection localities and GPS co-ordinates for all specimens are available in the project “[CHSPI] All spiders of Churchill, Manitoba” through the Barcode of Life Data Systems (BOLD) (http://www.boldsystems.org). A list of specimens and key metadata are also provided in Additional file1.
Diverse collecting methods were employed to maximize species recovery. Hand collecting was performed by sweep netting vegetation, by turning over stones and woody debris, and by searching lichen and moss substrates. Pan traps, Malaise traps, and Sticky traps (deployed in trees) yielded small numbers of specimens. Many specimens were collected in pitfall traps, made from white plastic containers (~10 cm diameter × 12 cm deep) that were placed along the marine shoreline and in fen, bog, tundra, and forested sites. 95% ethanol was added as a killing agent, and spiders were removed every two to four days. All specimens were then preserved in fresh 95% ethanol, and are now deposited at the Biodiversity Institute of Ontario, University of Guelph.
Specimen selection and identification
The selection of specimens for molecular analysis employed two strategies. From 2005–2008, every specimen (1507) was barcoded and the adult spiders were subsequently identified morphologically by GAB. This phase of the work led to the recovery of sequences from 1013 specimens. Overall, 87 species were collected during this period, but this approach led to ‘oversampling’ of common species (e.g. 161 barcode records for Pardosa lapponica). After 2009, an effort was made to sequence no more than 10 specimens per species; so spiders were identified morphologically to the species level, when possible, before barcoding. As a rule, adult spiders in our dataset were identified to the species level based on morphology, but all representatives of certain small-bodied spider families (mainly Linyphiidae and Theridiidae) were barcoded because of the difficulty in species discrimination through morphology. Most juveniles and some females were assigned to a species based on their sequence similarity (<2%) to specimens of the taxon that were identified through morphological study[26–28]. Barcode clusters that were distinct from all others (>2% divergence), but that contained only juveniles, could not be identified morphologically and were thus assigned interim species codes and treated as separate species for analysis. Information on the life stage (A-adult; I-Immature) of each specimen is available through its record on BOLD. Standard taxonomic references were used for identification including:[17, 19, 20, 29–66].
Whole specimens were arrayed in batches of 95 for databasing, photography, and tissue sampling, according to standard methods for high-throughput processing of specimens for DNA barcoding. One leg was then removed from each specimen and placed into one of the wells in a 96-well plate. When a specimen was too small for leg removal, it was placed into the well, and the voucher was recovered after DNA extraction.
DNA barcoding was performed using standard, high-throughput methods at the Canadian Centre for DNA Barcoding[69–71]. DNA extraction employed a glass-fibre protocol, while polymerase chain reactions (PCR) were performed using standard PCR cocktails. Primers were used to amplify the 658 bp barcode region of the cytochrome c oxidase subunit I (COI) gene, specifically the LepF1/LepR1 primers or the LCO1490_t1/HCO2198_t1 Folmer primer pair, tailed with M13. The PCR thermal regime included the following steps: 94°C for a minute; 5 replicates of 94°C for a minute, 45°C for 40 seconds, and 72°C for one minute; 35 cycles of a minute at 94°C, 40 seconds at 51°C, and 72°C for a minute; and concluding with five minutes at 72°C. Primers used for PCR amplification as well as cycle sequencing for each specimen are available through BOLD. Sequences were assembled using CodonCode Aligner v. 3.0.2 (CodonCode Corporation), and sequences were examined for indels and stop codons as a check against pseudogenes.
Analysis of genetic divergence
Analytical tools on BOLD were used to examine patterns of genetic divergence among the 2704 specimens with a sequence ≥500 bp. Nearest neighbour analysis (referred to as “barcode gap analysis” in BOLD3) plots the maximum pairwise divergence within a species against its minimum divergence to a different species. This plot indicates those cases where specimens can be reliably assigned to the correct species based on barcode analysis. Although the use of Pairwise Distance (p-distance) has been advocated by some authors, Kimura-2-Parameter (K2P) distances are similar unless nearest-neighbour distances are large (>12%) (Hebert, unpubl.). We employ K2P distances in our analysis partially for this reason, but also because this metric has been standard in prior barcoding studies. K2P and p-distances are reported as supplementary information (Additional file2) to enable comparison of the values. A neighbour-joining (NJ) phenogram employing the K2P distance model was constructed in MEGA5, employing pairwise deletion of missing sites and with bootstraps based upon 500 replicates, which was subsequently ultrametricized in MEGA. This tree is presented to visualize genetic divergences, not as a phylogenetic hypothesis for these species.
The completeness of sampling was visually assessed using the accumulation curve function on BOLD for the 2704 specimens with a sequence ≥500 bp, considering both species and barcode clusters (Barcode Index Numbers – BINs). This analysis resamples individuals with replacement, and we employed 100 iterations. The individual-based species richness estimator Chao1 was also calculated using EstimateS Version 8.2, with the default setting of 50 randomizations of input order. The composition of the fauna in terms of feeding guild was summarized by categorizing each species as an active predator, ambush predator, or web builder.
Results and discussion
Overview of the spiders of Churchill: diversity and distributions
COI sequences >500 bp were recovered from 77% of the specimens analyzed (2704/3506) (Additional file1, Additional file3). Among these records, 89% were fully compliant with the “barcode standard” as they possessed a sequence >500 bp with fewer than 1% Ns, and involved a record that was based on bidirectional sequence analysis. Sequencing success improved during the study, due largely to better preservation of specimens (e.g. more frequent ethanol exchange).
The joint morphological and DNA barcode analyses revealed 198 species representing 14 families and 98 genera (Table 1). This total includes 41% of the species of spiders known from Manitoba[1, 19] and 14% of those recorded from Canada and Alaska. Individual-based rarefaction curves based on both named species and BINs indicate that the fauna is well sampled (Figure 2). This conclusion is reinforced by the observation that just 34 species were represented by a single specimen, and 24 species by two individuals. Prior reports indicated the presence of 22 species in the Churchill region[1, 15] that we did not collect, but some of these identifications are questionable. Interestingly, the Chao1 diversity estimator suggested that 220.4 spider species (95% confidence interval of 207.6-250.2) occur in the Churchill region. We conclude that most spider species in this region are now known, but that 10–20 taxa await detection.
Juveniles represented 50.4% of the specimens collected, but they varied in abundance from 0% in the Hahniidae to 82% in the Tetragnathidae (Figure 3). However, 98% of the barcode clusters could be identified to a species because they included some adult specimens. This analysis indicated that the Linyphiidae dominated the fauna with 100 species, 50.5% of the total (Table1). Lycosidae were in second place with 19 species (9.6%), followed by Gnaphosidae (16 species; 8.1%) and Thomisidae (14 species; 7.1%). Another ten families were represented by fewer than 10 species each, jointly comprising 24.7% of the fauna: Araneidae (9 species), Theridiidae and Salticidae (8), Dictynidae (7), Philodromidae (6), Clubionidae (5), and Tetragnathidae (3). The remaining families (Amaurobiidae, Hahniidae, and Liocranidae) were each represented by a single species.
Half of the spider species (50.5%) at Churchill have a Holarctic distribution, while the remaining species are Nearctic (Figure 4). Table 1 lists the species detected and details their habitat preferences (arctic, sub-arctic, boreal) using assignments made by earlier authors[1, 39]. Arctic species inhabit stony tundra, pebbly beaches, gravel bars, patches of lichens, and the litter beneath plant species typical of the arctic. Subarctic species are most common in stony habitats and in habitats with scattered trees such as Populus and Salix. Finally, boreal species are associated with conifers, aspens, and other plants typical of the boreal forest. Fifteen species (7.7%) are typical of the Arctic zone (Table 1, Figure 3), with linyphiids (8 species) and lycosids (5 species) dominating. Another 29 species (14.8%) are sub-Arctic with a dominance of linyphiids (41.4%) and gnaphosids (24.1%). The remaining species (150; 76.5%) at Churchill are typical of the boreal zone with Linyphiidae (51.7%) and Lycosidae (6.9%) dominating. Four other species (2%) lack ecological data because they could not be morphologically identified, as only juveniles were collected, and they did not closely match any other sequences on BOLD or GenBank (June, 2013).
The spider fauna at Churchill included species with varied feeding strategies; 128 (64.6%) are web builders, 37 (18.7%) are ambush predators, and 33 (16.7%) are active predators.
Correspondence between morphological species and barcode clusters
There was strong correspondence between the boundaries of barcode clusters and species designations based on morphology. Nearly all species (97%, 159/164) represented by two or more individuals displayed a barcode gap (Figure 5), reflecting the fact that the maximum intraspecific divergence was less than the distance to the nearest neighbour. As well, most of these species (94%, 158/168) showed more than 2% divergence from their nearest neighbour. The other 34 species (those represented by a single specimen) all showed more than 2% divergence from their nearest neighbour, and most (31/34) had >4% divergence. Even prior to taxonomic reassessments motivated by the barcode results, it is clear that DNA barcoding is a very effective tool for identification of spiders. Moreover, the close correspondence between BINs and species (Figure 2) indicates the value of DNA barcoding as a quick tool for the determination of species richness in unstudied araneofaunas.
The 198 species included representatives of 98 genera and 14 families (Table 1), including one species new to science and three new for Canada. One wolf spider (Lycosidae), belonging to the Alopecosa pictilis group[20, 33], is probably undescribed and will be treated in a future publication (Blagoev and Dondale, unpubl.). Robertus lyrifer has a known Palaearctic distribution, and thus the “true” distribution could be Holarctic, which was previously overlooked, or this species may have been inadvertently introduced through ships visiting the port in Churchill. By contrast, Satilatlas monticola represents a range extension for a species previously only known from one locality in the USA[11, 19]. Here we present the first description of the female of that species.
New species for Canada
Family Theridiidae (cobweb weavers)
One of the new Canadian species (Figure 6), Robertus lyrifer Holm, has only previously been recorded from northern and central Europe[11, 85]. However, the diagnostic feature for males of this species—the shape of the left palp—was identical in the specimen from Churchill and its counterparts from Europe[47, 56]. As well, both specimens from Churchill showed close barcode similarity (0.5% divergence) to R. lyrifer from Russia (Figure 7).
Family Linyphiidae (dwarf and sheetweb weavers)
Baryphyma trifrons (O. P.-Cambridge), a Palearctic species which is very morphologically variable, currently includes ten synonyms. Two monophyletic clusters of this species with a minimum divergence of 6.4% occur at Churchill (Figure 8). One resembles B. trifrons affine (Schenkel), which is no longer recognized as a valid subspecies[11, 65], while the other resembles B. trifrons (O. P.-Cambridge). The sequences of B. trifrons affine from Churchill clustered with specimens from Ontario and British Columbia, while the second group clustered with a specimen from Russia. We conclude that the latter cluster represents B. trifrons. Although it is currently considered a synonym of B. trifrons affine, the barcode results challenge this conclusion, indicating the need for further taxonomic work (Figure 9).
Satilatlas monticola Millidge has until now been viewed as endemic to Elk Mountain, Colorado. Originally described from a single male, our collections included 36 individuals (12 ♂♂, 22 ♀♀, and 2 juveniles) of this taxon, enabling the first description of its female morphology.
Family Linyphiidae Blackwall, 1859
Genus Satilatlas Keyserling, 1886
Satilatlas monticola Millidge, 1981.
S. m. Millidge, 1981: 252, f. 16, 30–31.
Canada, Manitoba, Churchill - 4 ♂, 26 km SE Churchill, Twin Lakes, pt; lat. 58.6300, long. -93.7979; 29 m a.s.l.; 19-Jul-09; leg. D. Porco. - 1 ♂, 8 ♀, 16 km E Churchill, Bird Cove, pt; lat. 58.7639, long. -93.8970, 0 m; 20-Jul-09; leg. D. Porco. - 5 ♂, 4 ♀, 16 km E Churchill, Bird Cove, pt; lat. 58.7639, long. -93.8970, 0 m; 25-Jul-09; leg. G. Blagoev. - 1 ♂, 26 km SE Churchill, Twin Lakes, pt; lat. 58.6300, long. -93.8190, 34 m; 26-Jul-09; leg. D. Porco. - 1 ♂, 1 ♀, 26 km SE Churchill, Twin Lakes, pt; lat. 58.6300, long. -93.7979, 29 m; 27-Jul-09; leg. D. Porco. - 2 ♀, 16 km E Churchill, Bird Cove, pt; lat. 58.7639, long. -93.8970, 0 m; 27-Jul-09; leg. D. Porco. - 1 ♀, 26 km SE Churchill, Twin Lakes burn site, pt; lat. 58.6180, long. -93.8290, 53 m; 30-Jul-09; leg. G. Blagoev. - 1 ♂, Canada, 16 km E Churchill, Bird Cove, Rock Bluff A, grasses between ponds, close to pond 34; lat. 58.7718, long. -93.8439, 0 m; 08-Jul-10; leg. B. Laforest. - 3 ♀, 1 juvenile, 16 km E Churchill, Bird Cove, Rock Bluff A, ocean beach; lat. 58.7709, long. -93.8509, 7 m; 23-Jul-10; leg. V. Junea. - 2 ♀, 16 km E Churchill, Bird Cove, Rock Bluff A, ocean beach; lat. 58.7709, long. -93.8509, 7 m; 26-Jul-10; leg. V. Junea. - 1 ♀, 23 km E Churchill, Ramsay Creek, boreal forest; lat. 58.7304, long. -93.7805, 3 m; 30-Jul-10; leg. V. Junea. - 1 juvenile, 26 km SE Churchill, Twin Lakes fen, lat. 58.7666, long. -93.8529, 5 m; 02-Aug-10; leg. V. Junea.
The male of Satilatlas monticola was described by Millidge from a specimen taken under stones at an elevation of more than 3600 m a.s.l. at East Maroon Pass, Elk Mountains, Pitkin and Gunnison Counties, Colorado, USA.
The structure of the palp in Satilatlas monticola suggests its close relationship with Satilatlas gentilis. The male palp in specimens from Churchill clearly matched the illustrations in Millidge (Figure 10). The same resemblance was apparent in females of these two species as the shape of the epigyne in S. monticola is close to that in S. gentilis. However, the spermatheca in S. monticola is always inclined at an acute angle (Figure 11C, D), while that in S. gentilis is perpendicular to the central vertical axis of the epigyne. The epigyne of S. monticola also has a very broad, trapezium-shaped process which entirely covers the cavity with the openings to the sperm ducts.
Total length: 1.8-2.3 mm. Carapace (Figure 11A, B) dark brownish: 0.80 × 0.62, nearly circular in dorsal view. Chaetotaxy: F, Pt I-IV, 0-0-0-0; Ti I-III, 3-0-0-0; Ti IV, 5-0-0-0; Mt I-III, 1-0-0-0; Mt IV, 0-0-0-0. Cephalic region is differentiated from the rest of the prosoma by darker bands. Sternum smooth monotonous with the same color. Legs yellowish-brown with darker transverse stripes in the bases of the limbs. Leg IV > leg I > leg II > leg III (Table 2).
Specimens were found in wet areas near both Hudson Bay and inland ponds where it occurred among small stones and grass from mid-July to early August. Most specimens (27 adults) were collected in pitfall traps, but 7 adults and 2 juveniles were collected by hand.
Previously only known from its type locality in Colorado, the present records extend its range to Churchill, suggesting this species can be expected to occur in alpine and low arctic habitats in western North America.
High “intraspecific” divergences (>2%) were found in 27 species and all these cases merit critical study as candidates for cryptic species (Additional file3). However, some of these cases likely represent intraspecific variation as divergences greater than 2% have been reported in some arthropod species[6, 7, 86]. However, four Churchill species possessed >4% divergence and these taxa are discussed in more detail because they are the strongest candidates for cryptic species.
Family Araneidae (orbweavers)
The Holarctic species, Hypsosinga pygmaea (Sundevall), includes two deeply divergent (6.2%) sequence clusters at Churchill (Figure 12A). One cluster was also collected in central Canada (Alberta, Manitoba, Ontario), but the sole representative of the other cluster matched specimens from Russia and Finland (not included in the paper). Although the two groups could not be separated morphologically, their sympatric occurrence in Churchill suggests their status as sibling species.
A second Holarctic species, Larinioides cornutus (Clerck), also includes two haplotype clusters at Churchill with a minimum divergence of 5.9%. Interestingly, the two clusters are paraphyletic with another member of this genus, L. patagiatus (Figure 12B). The first cluster includes specimens from across Canada and the northern USA, while the second cluster is closely similar to sequences from various European countries. In fact, an identical haplotype was detected in eastern Asia (Kamchatka, Russia).
Family Dictynidae (meshweavers)
Dictyna major Menge, a morphologically distinctive taxon, includes two sequence clusters with a minimum divergence of 3.5% (Figure 12C). One group has representatives from five provinces (Alberta, British Columbia, Manitoba, Newfoundland and Labrador, Saskatchewan) and from the Yukon Territory. By contrast, specimens in the second cluster group with members of this species from eastern Russia as well as several European countries (data not included in this paper). The four Churchill sequences in group 2 are identical, and this low genetic variation is suggestive of a recent introduction.
Family Thomisidae (crab spiders)
Xysticus triangulosus Emerton, a Nearctic species, includes two clusters at Churchill with a minimum distance of 5.5%. Both clusters were also collected in the Yukon (Figure 12D). As members of these clusters appear morphologically indistinguishable, future work should test for evidence of divergence at nuclear loci which would signal their status as distinct species.
Species with low barcode divergence
Although different species usually show more than 2% interspecific divergence, lower levels of sequence divergence should occur in young species, and they have been detected in many groups[87, 88]. In some extreme cases, valid species pairs differ by only a single bp in the barcode region or not at all. Two cases of young species assemblages were detected in this study involving species of Pardosa and Erigone (Figure 13).
Nine species of Pardosa were present at Churchill, most well separated by barcodes. However, four of these species (Pardosa groenlandica, P. dromaea, P. furcifera, P. podhorskii), belonging to the Pardosa modica group, showed limited divergence (Figure 13A). In particular, the minimum distance between P. groenlandica and P. dromaea was 0.8%, while that between P. furcifera and P. podhorskii was 1.2%. Although these are considered as “good species”, they can only be distinguished by genitalic characters. Their shallow genetic divergences suggest a recent origin, a fact which explains their limited morphological divergence. Our results, as well as the conclusions of other researchers (, Dondale pers. comm.), suggest the P. modica group needs revision. A similar case was observed in Erigone (Figure 13B), where three species (Erigone arctica, E. arctophylacis, E. dentigera) possess a minimum inter-specific distance of 1.4%.
The fact that some species assemblages show low sequence divergences does not compromise the use of DNA barcoding for their identification[22, 90]. Actually, all of the closely related species at Churchill formed distinct barcode groups. However, the presence of species such as this demonstrates the importance of the involvement of taxonomic specialists in the construction of DNA barcode reference libraries.
This study has developed the first comprehensive DNA barcode reference library for the spider fauna of any region. The results indicate that DNA barcodes permit the discrimination of all species present at Churchill. Given the prevalence of juvenile spiders in most collections, DNA barcoding is a powerful tool for the identification of specimens, an important advance for future biomonitoring programs. Because the vast majority of barcode clusters correspond with a named species, the incidence of cryptic species appears to be low in northern spiders. The strong morphological/molecular correspondence indicates that prior morphological studies have been effective in species recognition in spiders, a situation which contrasts with that in several other groups at Churchill, especially parasitoid members of the order Hymenoptera[5, 10]. This suggests that speciation in parasitoids, which tend to be host specific, is often associated only with biochemical evolution (e.g. in olfaction and immunity) rather than external morphological differentiation. This apparently contrasts with speciation in spiders, which is typically accompanied by genital and other morphological divergence. The present study did, however, detect four cases in which the prospect for cryptic species is high, and further studies on the other species showing high intraspecific divergence will likely extend the number of such cases.
Statistical analysis of the relationship between species discovery and sample size suggested that only about 20 species of spiders await detection at Churchill. However, because the present collections were made during the snow-free season, vernal species associated with snow edges were unlikely to be sampled. Because our work failed to detect 22 species reported in earlier work at Churchill[1, 15], the Churchill fauna may include nearly 250 species. As with other arthropod groups, the spider fauna at Churchill includes a mix of Nearctic and Holarctic species. The small-bodied, web-building Linyphiidae was dominant (50.5% of species), followed by the active predators Lycosidae (9.6%), and two families of ambush predators, Gnaphosidae (8.1%) and Thomisidae (7.1%).
Our study has revealed a remarkable diversity of spider species in the Churchill region, increasing the fauna from 64 to 198 species. It also provides an important foundation for future biomonitoring, ecological studies, and taxonomic investigations.
Canadian centre for DNA barcoding
Barcode of Life Data Systems
Churchill Northern Studies Centre
Cytochrome c Oxidase subunit I
Polymerase chain reaction
Above sea level
Benell-Aitchison CW, Dondale CD: A Checklist of Manitoba Spiders (Araneae) with notes on geographic relationships. Nat Can. 1990, 117: 215-237.http://www.npwrc.usgs.gov/resource/insects/spiders/index.htm,
Zhou X, Adamowicz SJ, Jacobus LM, DeWalt RE, Hebert PDN: Towards a comprehensive barcode library for arctic life - Ephemeroptera, Plecoptera, and Trichoptera of Churchill, Manitoba, Canada. Front Zool. 2009, 6: 30-10.1186/1742-9994-6-30.
Zhou X, Jacobus LM, DeWalt RE, Adamowicz SJ, Hebert PDN: Ephemeroptera, Plecoptera, and Trichoptera fauna of Churchill (Manitoba, Canada): insights into biodiversity patterns from DNA barcoding. J N Am Benthol Soc. 2010, 29: 814-837. 10.1899/09-121.1.
Smith MA, Fernandez-Triana J, Roughley R, Hebert PDN: DNA barcode accumulation curves for understudied taxa and areas. Mol Ecol Res. 2009, 9 (Suppl 1): 208-216.
Fernandez-Triana J, Smith MA, Boudreault C, Goulet H, Hebert PDN, Smith AC, Roughley R: A poorly known high-latitude parasitoid wasp community: unexpected diversity and dramatic changes through time. PLoS One. 2011, 6 (8): e23719-10.1371/journal.pone.0023719.
Jeffery NW, Elías-Gutiérrez M, Adamowicz SJ: Species diversity and phylogeographical affinities of the Branchiopoda (Crustacea) of Churchill, Manitoba, Canada. PLoS One. 2011, 6 (Suppl 5): e18364-
Renaud AK, Savage J, Adamowicz SJ: DNA barcoding of Northern Nearctic Muscidae (Diptera) reveals high correspondence between morphological and molecular species limits. BMC Ecol. 2012, 12: 24-10.1186/1472-6785-12-24.
Young MR, Behan-Pelletier VM, Hebert PDN: Revealing the hyperdiverse mite fauna of subarctic Canada through DNA barcoding. PLoS One. 2012, 7: e48755-10.1371/journal.pone.0048755.
Ruiter DE, Boyle EE, Zhou X: DNA barcoding facilitates associations and diagnoses for Trichoptera larvae of the Churchill (Manitoba, Canada) area. BMC Ecol. 2013, 13: 5-10.1186/1472-6785-13-5.
Stahlhut JK, Fernández-Triana J, Adamowicz SJ, Buck M, Goulet H, Hebert PDN, Huber JT, Merilo MT, Sheffield CS, Woodcock T, Smith MA: DNA barcoding reveals diversity of Hymenoptera and the dominance of parasitoids in a sub-arctic environment. BMC Ecol. 2013, 13: 2-10.1186/1472-6785-13-2.
Platnick NI: The world spider catalog, version 14.0. Am Mus Nat Hist. 2013, [http://research.amnh.org/entomology/spiders/catalog/index.html],
Turnbull AL: Ecology of the true spiders (Araneomorphae). Ann Rev Ent. 1973, 18: 305-348. 10.1146/annurev.en.18.010173.001513.
Uetz GW: The influence of variation in litter habitats on spider communities. Oecologia. 1979, 40: 29-42. 10.1007/BF00388808.
Weeks RDJ, Holtzer TO: Habitat and season in structuring ground-dwelling spider (Araneae) communities in a shortgrass steppe ecosystem. Envir Entomol. 2000, 29: 1164-1172. 10.1603/0046-225X-29.6.1164.
McClure HE: Aspection in the biotic communities of the Churchill area, Manitoba. Ecol Monogr. 1943, 13 (Suppl 1): 1-35.
Chamberlin RV, Ivie W: New genera and species of North American linyphiid spiders. Bull Univ Utah. 1943, 33 (Suppl 10): 1-39.
Millidge AF: The erigonine spiders of North America. Part 7. Miscellaneous genera. J Arachnol. 1984, 12: 121-169.
Levi HW: Small orb-weavers of the genus Araneus north of Mexico (Araneae: Araneidae). Bull Mus Comp Zool. 1973, 145: 473-552.
Millidge AF: The erigonine spiders of North America. Part 5. The genus Satilatlas (Araneae, Linyphiidae). Bull Am Mus nat Hist. 1981, 170: 242-253.
Dondale CD, Redner JH: The Wolf Spiders, Nurseryweb Spiders, and Lynx Spiders of Canada and Alaska, Araneae: Lycosidae, Pisauridae, and Oxyopidae. The Insects and Arachnids of Canada, Part 17. 1990, Ottawa: Biosystematics Research Institute
Hebert PDN, Cywinska A, Ball SL, deWaard JR: Biological identification through DNA barcodes. Proc R Soc Lond B. 2003, 270: 313-321. 10.1098/rspb.2002.2218.
Hebert PDN, Ratnasingham S, deWaard JR: Barcoding animal life: cytochrome c oxidase subunit 1 divergences among closely related species. Proc R Soc Lond B. 2003, 270: S596-S599.
Kuzmina ML, Johnson KL, Barron HR, Hebert PDN: Identification of the vascular plants of Churchill, Manitoba, using a DNA barcode library. BMC Ecol. 2012, 12: 25-10.1186/1472-6785-12-25.
Ratnasingham S, Hebert PDN: BOLD : The Barcode of Life Data System. Mol Ecol Notes. 2007, 7: 355-364. 10.1111/j.1471-8286.2007.01678.x.http://www.barcodinglife.org,
Martin JEH: Collecting, preparing, and preserving insects, mites, and spiders. The Insects and Arachnids of Canada, Part 1. 1977, Ottawa: Biosystematics Research Institute
Barrett RDH, Hebert PDN: Identifying spiders through DNA barcodes. Can J Zool. 2005, 83: 481-491. 10.1139/z05-024.
Robinson EA, Blagoev GA, Hebert PDN, Adamowicz SJ: Prospects for using DNA barcoding to identify spiders in species-rich genera. ZooKeys. 2009, 16 (Special issue): 27-46.
Slowik J, Blagoev G: First description of the male spider Pacifiphantes magnificus (Chamberlin & Ivie) (Araneae: Linyphiidae). Zootaxa. 2012, 3481: 73-81.
Chamberlin RV, Gertsch WJ: The spider family Dictynidae in America north of Mexico. Bull Am Mus nat Hist. 1958, 116: 1-152.
Chamberlin RV, Ivie W: A hundred new species of American spiders. Bull Univ Utah. 1942, 32 (Suppl 13): 1-117.
Dondale CD: Revision of the groenlandica subgroup of the genus Pardosa (Araneae, Lycosidae). J Arachnol. 1999, 27: 435-448.
Dondale CD, Redner JH: The Crab Spiders of Canada and Alaska, Araneae: Philodromidae and Thomisidae. The Insects and Arachnids of Canada, Part 5. 1978, Ottawa: Biosystematics Research Institute
Dondale CD, Redner JH: Revision of the wolf spider genus Alopecosa Simon in North America (Araneae: Lycosidae). Can Ent. 1979, 111: 1033-1055. 10.4039/Ent1111033-9.
Dondale CD, Redner JH: The Sac Spiders of Canada and Alaska, Araneae: Clubionidae and Anyphaenidae. The Insects and Arachnids of Canada, Part 9. 1982, Ottawa: Biosystematics Research Institute
Dondale CD, Redner JH: Revision of the wolf spiders of the genus Arctosa C. L. Koch in North and Central America (Araneae: Lycosidae). J Arachnol. 1983, 11: 1-30.
Dondale CD, Redner JH: Revision of the milvina group of the wolf spider genus Pardosa (Araneae: Lycosidae). Psyche. 1984, 91: 67-117. 10.1155/1984/49787.
Dondale CD, Redner JH: The coloradensis, xerampelina, lapponica, and tesquorum groups of the genus Pardosa (Araneae: Lycosidae) in North America. Can Ent. 1986, 118: 815-835. 10.4039/Ent118815-8.
Dondale CD, Redner JH: The atrata, cubana, ferruginea, moesta, monticola, saltuaria, and solituda groups of the spider genus Pardosa in North America (Araneae: Lycosidae). Can Ent. 1987, 119: 1-19. 10.4039/Ent1191-1.
Dondale CD, Redner JH, Marusik YM: Spiders (Araneae) of the Yukon. Insects of the Yukon. Edited by: Danks HV, Downes JA. 1997, Ottawa: [Biological Survey of Canada (Terrestrial Arthropods), vol. 2.], 73-113.
Dondale CD, Redner JH, Paquin P, Levi HW: The orb-weaving spiders of Canada and Alaska (Araneae: Uloboridae, Tetragnathidae, Araneidae, Theridiosomatidae). The Insects and Arachnids of Canada, Part 23. 2003, Ottawa: NRC Research Press
Ivie W: The spiders of the genus Islandiana (Linyphiidae, Erigoninae). Am Mus Novit. 1965, 2221: 1-25.
Ivie W: North American spiders of the genus Bathyphantes (Araneae, Linyphiidae). Am Mus Novit. 1969, 2364: 1-70.
Kaston BJ: New Micryphantidae and Dictynidae with notes on other spiders. Am Mus Novit. 1945, 1292: 1-14.
Kronestedt T, Marusik YM: Studies on species of Holarctic Pardosa groups (Araneae, Lycosidae). VII. The Pardosa tesquorum group. Zootaxa. 2011, 3131: 1-34.
Leech RE: The spiders (Araneida) of Hazen Camp 81°49′N, 71°18′W. Quaest ent. 1966, 2: 153-212.
Leech RE: A revision of the Nearctic Amaurobiidae (Arachnida: Araneida). Mem ent Soc Can. 1972, 84: 1-182.
Le Peru B: The spiders of Europe, a synthesis of data: Volume 1. Atypidae to Theridiidae. Mém Soc Linn Lyon. 2011, 2: 1-522.
Levi HW: The spider genera Enoplognatha, Theridion and Paidisca in America north of Mexico (Araneae, Theridiidae). Bull Am Mus nat Hist. 1957, 112: 1-123.
Levi HW: The diademanis group of the orbweaver genus Araneus north of Mexico (Araneae: Araneidae). Bull Mus comp Zool. 1971, 141: 131-179.
Levi HW: The American orb-weaver genera Dolichognatha and Tetragnatha north of Mexico (Araneae: Araneidae, Tetragnathinae). Bull Mus comp Zool. 1981, 149: 271-318.
Marusik YM, Koponen S, Vinokurov NN, Nogovitsyna SN: Spiders (Aranei) from northernmost forest-tundra of northeastern Yakutia (70°35′N, 134°34′E) with description of three new species. Arthr Sel. 2002, 10: 351-370.
Marusik YM, Fritzén NR: On a new Dictyna species (Araneae, Dictynidae) from the northern Palaearctic confused with the east Siberian D. schmidti Kulczyn’ski, 1926. ZooKeys. 2011, 138: 93-108. 10.3897/zookeys.138.1849.
Marusik YM, Koponen S: A review of the Holarctic genus Tmeticus Menge, 1868 (Araneae, Linyphiidae), with a description of a new genus. ZooKeys. 2010, 59: 15-37.
Omelko MM, Marusik YN, Koponen S: A survey of the east Palearctic Lycosidae (Aranei). 8. The genera Pirata Sundevall, 1833 and Piratula Roewer, 1960 in the Russian Far East. Arthr Sel. 2011, 20: 195-232.
Opell BD, Beatty JA: The Nearctic Hahniidae (Arachnida: Araneae). Bull Mus comp Zool. 1976, 147: 393-433.
Palmgren P: Die Spinnenfauna Finnlands und Ostfennoskandiens. V. Theridiinae und Nesticidae. Fauna Fenn. 1974, 26: 1-54.
Paquin P, Dupérré N: Guide d’identification des araignées de Québec. Fabreries. 2003, 11: 1-251.
Platnick NI, Dondale CD: The ground spiders of Canada and Alaska (Araneae: Gnaphosidae). The Insects and Arachnids of Canada, Part 19. 1992, Ottawa: Centre for Land and Biological Resources, Research Branch
Platnick NI, Shadab MU: A revision of the spider genus Gnaphosa (Araneae, Gnaphosidae) in America. Bull Am Mus nat Hist. 1975, 155: 1-66.
Platnick NI, Shadab MU: A revision of the spider genera Haplodrassus and Orodrassus (Araneae, Gnaphosidae) in North America. Am Mus Novit. 1975, 2583: 1-40.
Platnick NI, Shadab MU: A revision of the spider genera Drassodes and Tivodrassus (Araneae, Gnaphosidae) in North America. Am Mus Novit. 1976, 2593: 1-29.
Platnick NI, Shadab MU: A revision of the American spiders of the genus Drassyllus (Araneae, Gnaphosidae). Bull Am Mus nat Hist. 1982, 173: 1-97.
Platnick NI, Shadab MU: A revision of the American spiders of the genus Zelotes (Araneae, Gnaphosidae). Bull Am Mus nat Hist. 1983, 174: 97-192.
Platnick NI, Shadab MU: A revision of the American spiders of the genus Micaria (Araneae, Gnaphosidae). Am Mus Novit. 1988, 2916: 1-64.
Tanasevitch AV: On synonymy of linyphiid spiders of the Russian fauna (Arachnida: Aranei: Linyphiidae). 2. Arthr Sel. 2011, 20: 129-143.
Spiders of North America: An Identification Manual. Edited by: Ubick D, Paquin P, Cushing PE, Roth V. 2005, American Arachnological Society
Borisenko AV, Sones J, Hebert PDN: The front-end logistics of DNA barcoding: challenges and prospects. Mol Ecol Res. 2009, 9 (Suppl 1): 27-34.
Porco D, Rougerie R, Deharveng L, Hebert P: Coupling non-destructive DNA extraction and voucher retrieval for small soft-bodied arthropods in a high-throughput context: the example of Collembola. Mol Ecol Res. 2010, 210 (Suppl 6): 942-945.
Ivanova N, deWaard J, Hebert P: Canadian Centre for DNA Barcoding Protocols, Glass Fiber Plate DNA Extraction. 2007, (Accessed on Date). [http://www.dnabarcoding.ca/CCDB_DOCS/CCDB_DNA_Extraction.pdf]
Ivanova NV, Grainger CM: Canadian Centre for DNA Barcoding Protocols, COI amplification. 2007a, (Accessed on Date). [http://www.dnabarcoding.ca/CCDB_DOCS/CCDB_Amplification.pdf]
Ivanova NV, Grainger CM: Canadian Centre for DNA Barcoding Protocols, sequencing. 2007b, (Accessed on Date). [http://www.dnabarcoding.ca/CCDB_DOCS/CCDB_Sequencing.pdf]
Ivanova NV, deWaard JR, Hebert PDN: An inexpensive, automation-friendly protocol for recovering high-quality DNA. Mol Ecol Notes. 2006, 6: 998-1002. 10.1111/j.1471-8286.2006.01428.x.
Hebert PDN, Penton EH, Burns JM, Janzen DH, Hallwachs W: Ten species in one: DNA barcoding reveals cryptic species in the neotropical skipper butterfly Astraptes fulgerator. Proc Natl Acad Sci USA. 2004, 101: 14812-14817. 10.1073/pnas.0406166101.
Folmer O, Black M, Hoch W, Lutz R, Vrijenhoek R: DNA primers for amplification of mitochondrial cytochrome c oxidase subunit I from diverse metazoan invertebrates. Mol Mar Biol Biotech. 1994, 3: 294-299.
Messing J: New M13 vector for cloning. Meth Enzym. 1983, 101: 20-78.
Collins RA, Cruickshank RH: The seven deadly sins of DNA barcoding. Mol Ecol Res. 2012, 13: 969-975.
Collins RA, Boykin LM, Cruickshank RH, Armstrong KF:Barcoding’s next top model: an evaluation of nucleotide substitution models for specimen identification. Meth Ecol Evol. 2012, 3: 457-465. 10.1111/j.2041-210X.2011.00176.x.
Kimura M: A simple method for estimating evolutionary rate of base substitutions through comparative studies of nucleotide sequences. J Mol Evol. 1980, 16: 111-120. 10.1007/BF01731581.
Saitou N, Nei M: The neighbor-joining method - a new method for reconstructing phylogenetic trees. Mol Biol Evol. 1987, 4: 406-425.
Tamura K, Peterson D, Peterson N, Stecher G, Nei M, Kumar S: MEGA5: Molecular Evolutionary Genetics Analysis Using Maximum Likelihood, Evolutionary Distance, and Maximum Parsimony Methods. Mol Biol Evol. 2011, 28: 2731-2739. 10.1093/molbev/msr121.
Ratnasingham S, Hebert PDN: A DNA-based registry for all animal species: The Barcode Index Number (BIN) System. PLoS One. 2013, 8 (7): e66213-10.1371/journal.pone.0066213.
Gotelli NJ, Colwell RK: Estimating species richness. Biological diversity: frontiers in measurement and assessment. Edited by: Magurran AE, McGill BJ. 2011, New York: Oxford University Press, 39-54.
Cowell RK: EstimateS: Statistical Estimation of Species Richness and Shared Species from Samples. 2011, Version 8. Persistent URL [http://purl.oclc.org/estimates]
Paquin P, Buckle DJ, Dupérré N, Dondale CD: Checklist of the spiders (Araneae) of Canada and Alaska. Zootaxa. 2010, 246: 1-170.
Nentwig W, Blick T, Gloor D, Hänggi A, Kropf C: Spiders of Europe. 2013, Version 11 [http://www.araneae.unibe.ch]
Meyer CP, Paulay G: DNA barcoding: error rates based on comprehensive sampling. PLoS Biol. 2005, 3: 2229-2238.
Nazari V, Larsen TB, Lees DC, Brattström O, Bouyer T, Van de Poel G, Hebert PDN: Phylogenetic systematics of Colotis and associated genera (Lepidoptera: Pieridae): evolutionary and taxonomic implications. J Zool Syst Evolut Res. 2011, 49: 204-215. 10.1111/j.1439-0469.2011.00620.x.
Mutanen M, Hausmann A, Hebert PDN, Landry J-F, deWaard JR, Huemer P: Allopatry as a Gordian knot for taxonomists: Patterns of DNA barcode divergence in arctic-alpine Lepidoptera. PLoS One. 2012, 7 (Suppl 10): e47214-
Burns JM, Janzen DH, Hajibabaei M, Hallwachs W, Hebert PDN: DNA barcodes of closely related (but morphologically and ecologically distinct) species of Skipper butterflies (Hesperiidae) can differ by only one to three nucleotides. J Lepidopterists’ Soc. 2007, 61 (Suppl 3): 138-153.
Sauer J, Hausdorf B: Reconstructing the evolutionary history of the radiation of the land snail genus Xerocrassaon on Crete based on mitochondrial sequences and AFLP markers. BMC Evol Biol. 2010, 10: 299-10.1186/1471-2148-10-299.
We thank students from the Arctic Ecology field course offered by the University of Guelph for contributing specimens. We are also grateful for support provided by NSERC’s International Polar Year (PDNH) and Discovery Grant (SJA) programs. DNA sequencing was largely funded by the Government of Canada through Genome Canada and the Ontario Genomics Institute in support of the International Barcode of Life Project. We also thank the Ontario Ministry of Research and Innovation for funding the ongoing development of BOLD, which was essential for data management and analysis. We thank staff at the Canadian Centre for DNA Barcoding at the University of Guelph for molecular analysis, and Kathrin Sim at McGill University for providing specimens of Pardosa glacialis. We also thank Ari Kakko and Marko Mutanen for providing access to unpublished sequences of Larinioides cornutus from Finland. Special thanks to Suzanne Bateson for providing graphic assistance with some figures. The Churchill Northern Studies Centre (CNSC) provided valuable logistical support throughout this endeavour as well as a grant through their Northern Research Fund.
The authors declare that they have no competing interests.
GAB conducted field collecting, performed the morphological identifications, managed the BOLD projects, performed the analysis of the molecular data, and wrote the taxonomic insights. NIN participated in sequence analysis, including sequence editing, sequence alignment, and data validation. CNS performed statistical analysis and prepared some of the figures. SJA contributed to the conception and analyzed the sequence data. PDNH provided institutional support and led the grant applications funding the study. GAB, PDNH, and SJA designed and conducted the study. GAB, SJA, and PDNH wrote the manuscript. All authors read and approved the final manuscript.
Electronic supplementary material
Authors’ original submitted files for images
Below are the links to the authors’ original submitted files for images.
About this article
Cite this article
Blagoev, G.A., Nikolova, N.I., Sobel, C.N. et al. Spiders (Araneae) of Churchill, Manitoba: DNA barcodes and morphology reveal high species diversity and new Canadian records. BMC Ecol 13, 44 (2013). https://doi.org/10.1186/1472-6785-13-44
- Cytochrome c oxidase subunit I
- DNA barcoding
- Barcoding biotas