Find research datasets worth reusing

FIGURE 4. Juvenile A in Cherax latimanus sp. nov., a new burrow-dwelling freshwater crayfish (Decapoda Parastacidae) from the mid-Murray River catchment, Australia

FIGURE 4. Juvenile A) Cherax latimanus sp. nov., 10.9 mm OCL, roadside drain, Nelson Road, collected with holotype (note, telson held underneath), for comparison with B) C. destructor, 11.1 mmm OCL, farm dam, Port Stephens (Images: Robert Mc- Cormack).

FIGURE 1 in Cherax latimanus sp. nov., a new burrow-dwelling freshwater crayfish (Decapoda Parastacidae) from the mid-Murray River catchment, Australia

FIGURE 1. Cherax latimanus sp. nov., holotype, NMV J74790, male, 63.6 mm OCL, roadside drain on south-east side of Nelson Road, near Benalla/Yarrawonga Road, (near Benalla), Victoria (Image: Rob McCormack).

FIGURE 7 in Cherax latimanus sp. nov., a new burrow-dwelling freshwater crayfish (Decapoda Parastacidae) from the mid-Murray River catchment, Australia

FIGURE 7. Earthen roadside drain with Cherax latimanus sp. nov. burrows (lighter patches) (Image: Robert McCormack).

FIGURE 2 in Cherax latimanus sp. nov., a new burrow-dwelling freshwater crayfish (Decapoda Parastacidae) from the mid-Murray River catchment, Australia

FIGURE 2. Cherax latimanus sp. nov., dorsal, ventral and lateral view of preserved holotype, NMV J74790, 63.6 mm OCL (Images: Tarmo A. Raadik).

opencc-zeroDec 2021View details →

dryad32/100

Lineage-level distribution models lead to more realistic climate change predictions for a threatened crayfish

Aim: As climate change presents a major threat to biodiversity in the next decades, it is critical to assess its impact on species habitat suitability to inform biodiversity conservation. Species distribution models (SDMs) are a widely used tool to assess climate change impacts on species' geographical distributions. As the term suggests, the species-level is the most commonly used taxonomic unit in SDMs. However, recently it has been demonstrated that SDMs considering taxonomic resolution below (or above) the species-level can make more reliable predictions of biodiversity change when different populations exhibit local adaptation. Here, we tested this idea using the Japanese crayfish (Cambaroides japonicus), a threatened species encompassing two geographically structured and phylogenetically distinct genetic lineages. Location: Northern Japan. Methods: We first estimated niche differentiation between the two lineages of C. japonicus using n-dimensional hypervolumes, then made climate change predictions of habitat suitability using SDMs constructed at two phylogenetic levels: species and intraspecific lineage. Results: Our results showed only intermediate niche overlap, demonstrating measurable niche differences between the two lineages. The species-level SDM made future predictions that predicted much broader and severe impacts of climate change. However, the lineage-level SDMs led to reduced climate change impacts overall, and also suggested that the eastern lineage may be more resilient to climate change than the western one. Main conclusions: The two lineages of C. japonicus occupy different niche spaces. Compared with lineage-level models, species-level models can overestimate climate change impacts. These results not only have important implications for designing future conservation strategies for this threatened species, but also highlight the need for incorporating genetic information into SDMs to obtain realistic predictions of biodiversity change.

dryad32/100

Motion‐triggered laser photography shows burrowing crayfish activity patterns

1. Burrowing crayfish represent 15% of total crayfish species and 32% of imperiled species. Few life history studies exist for these species and more information is needed regarding their ecology, population status, distribution, and biogeography for effective conservation efforts. Challenges to gaining such information include sampling difficulty and small sample sizes. Collection efforts may be more efficient if activity patterns can be identified for species of interest. The goal of our study was to assess specific environmental indicators of burrowing crayfish activity patterns. 2. We evaluated activity patterns of two primary burrowing crayfish species, Lacunicambarus erythrodactylus Simon & Morris, 2014 and Procambarus holifieldi Schuster, Taylor & Adams, 2015 using laser-triggered digital photography for one-year periods in the Bogue Chitto Creek floodplain, Dallas County, Alabama, U.S.A. We predicted that activity would be related to time of day, season, groundwater depth, and precipitation. 3. Activity by L. erythrodactylus covaried significantly with time of day, daylength, groundwater temperature, and relative air temperature, while activity by P. holifieldi covaried with time of day, season, groundwater temperature, and relative air temperature. Additionally, burrow chimney construction by P. holifieldi covaried with daylength, groundwater temperature, relative air temperature, and precipitation. 4. Out-of-burrow activity for both species was greatest at night and during periods of relatively cool groundwater temperatures and relatively warm air temperatures, which may be linked to thermal regulation behavior. The probability of chimney construction by P. holifieldi increased with increasing daylength and decreasing precipitation and was highest during periods of cool groundwater temperatures and air temperatures. A distinct lull in activity from October through March for both species was likely the result of reproductive behaviors such as period of egg production and incubation within burrows. 5. Identifying peak out-of-burrow activity periods for burrowing crayfish will allow collection efforts to be focused on periods of greatest activity, thereby facilitating the study of burrowing crayfish behavior.

opencc-zeroSep 2021View details →

FIGURE 5. Euastacus clydensis Riek, 1969. A in Redescription of Euastacus clydensis Riek, 1969 (Crustacea: Parastacidae), a valid species of spiny crayfish from southern New South Wales, Australia

FIGURE 5. Euastacus clydensis Riek, 1969. A, distribution, sampling locations (green) in Moss Vale, Jervis Bay and Batemans Bay (grey shading: the Murray-Darling Basin; dark blue dashed lines: South East Coast Drainage river catchments; and light blue lines indicate major rivers); B–D, foraging individuals and habitat, Quart Pot Creek, tributary of Buckenbowra River (specimens not collected); E, habitat, Carters Creek, tributary of Buckenbowra River.

FIGURE 4. A in Redescription of Euastacus clydensis Riek, 1969 (Crustacea: Parastacidae), a valid species of spiny crayfish from southern New South Wales, Australia

FIGURE 4. A, Euastacus clydensis Riek, 1969, male holotype (OCL 73.37 mm), Clyde River, NSW, AM P15491, right antenna (ventral view); B, E. clydensis Riek, 1969, male, OCL 71.85 mm, Currowan Creek, NSW, ACP4767, right scaphocerite (ventral view); C, E. spinifer (Heller, 1865), female, OCL 73.43 mm, Waterfall, NSW, AM G1502, right scaphocerite (ventral view).

FIGURE 3. Euastacus clydensis Riek, 1969 in Redescription of Euastacus clydensis Riek, 1969 (Crustacea: Parastacidae), a valid species of spiny crayfish from southern New South Wales, Australia

FIGURE 3. Euastacus clydensis Riek, 1969, male holotype (OCL 73.37 mm), Clyde River, NSW, AM P15491: A, anterior cephalothorax including epistome, ventral view; B, left first chela, dorsal view; C–D, right first chela, dorsal and ventral views; E, right maxilliped 3; F, cephalothorax, ventral view.

FIGURE 2. Euastacus clydensis Riek, 1969 in Redescription of Euastacus clydensis Riek, 1969 (Crustacea: Parastacidae), a valid species of spiny crayfish from southern New South Wales, Australia

FIGURE 2. Euastacus clydensis Riek, 1969, male holotype (OCL 73.37 mm), Clyde River, NSW, AM P15491: A, carapace, dorsal view; B, carapace, right lateral view; C, abdomen, right oblique dorsal view; D, abdomen, right lateral view; E, telson and uropods, dorsal view.

FIGURE 6 in Redescription of Euastacus clydensis Riek, 1969 (Crustacea: Parastacidae), a valid species of spiny crayfish from southern New South Wales, Australia

FIGURE 6. Maximum likelihood phylogeny inferred from mitochondrial COI sequence data of Euastacus spinifer (Heller, 1865), E. vesper McCormack & Ahyong, 2017, E. clydensis Riek, 1969. Values on nodes correspond to bootstrap percentages (>75%) and posterior probabilities (>0.95).

FIGURE 1. Euastacus clydensis Riek, 1969 in Redescription of Euastacus clydensis Riek, 1969 (Crustacea: Parastacidae), a valid species of spiny crayfish from southern New South Wales, Australia

FIGURE 1. Euastacus clydensis Riek, 1969, male holotype (OCL 73.37 mm), Clyde River, NSW, AM P15491: A) dorsal habitus; B) ventral habitus.

FIGURE 11 in Integrative taxonomy reveals two new narrowly-endemic crayfish species (Decapoda: Cambaridae) from the Yadkin River Basin in western North Carolina, USA

FIGURE 11. Hypothesized passive margin escarpment evolution (PMEE) time series of the Stony Fork watershed (figure concept adapted from Prince et al. 2010). i) The initial Eastern Continental Divide (ECD) demarcated the higher-gradient, moderate elevation Yadkin River basin and moderate-gradient, higher elevation New River basin; the basins did not share an ancestral Cambarus species. ii) Erosion along the higher-gradient eastern slope of the ECD (dotted line) captured the headwaters of a historic New River Basin stream, bringing ancestral C. aff. robustus into the Yadkin basin and forcing a downstream retreat of ancestral C. species C. iii) Additional erosional events (dotted lines) pushed the ECD further inland and demarcated extant interior basin species from Atlantic Slope species; Cambarus lapidosus is isolated from C. aff. robustus in the Stony Fork headwaters by the extant ECD and from downstream C. species C by a natural waterfall barrier.

FIGURE 4 in Integrative taxonomy reveals two new narrowly-endemic crayfish species (Decapoda: Cambaridae) from the Yadkin River Basin in western North Carolina, USA

FIGURE 4. Cambarus lapidosus, holotype (NCSM 90222) in life (photo credit: Michael A. Perkins, NCWRC).

FIGURE 7 in Integrative taxonomy reveals two new narrowly-endemic crayfish species (Decapoda: Cambaridae) from the Yadkin River Basin in western North Carolina, USA

FIGURE 7. Cambarus burchfielae, new species. (A.) Lateral view of carapace; (B.) dorsal view of carapace; (C.) right antennal scale; (D.) dorsal view of carpus and chela; (E.) epistome; (F.) lateral and (G.) mesial view of form I gonopod; (H.) lateral and (I.) mesial view of form II gonopod; (J.) annulus ventralis. A–E, F–G from holotype; H–I from morphotype; J from allotype.

FIGURE 3 in Integrative taxonomy reveals two new narrowly-endemic crayfish species (Decapoda: Cambaridae) from the Yadkin River Basin in western North Carolina, USA

FIGURE 3. Cambarus lapidosus, new species. (A.) Lateral view of carapace; (B.) dorsal view of carapace; (C.) right antennal scale; (D.) dorsal view of carpus and chela; (E.) epistome; (F.) lateral and (G.) mesial view of form I gonopod; (H.) lateral and (I.) mesial view of form II gonopod; (J.) annulus ventralis. A–E, F–G from holotype; H–I from morphotype; J from allotype.

FIGURE 2 in Integrative taxonomy reveals two new narrowly-endemic crayfish species (Decapoda: Cambaridae) from the Yadkin River Basin in western North Carolina, USA

FIGURE 2. Bayesian phylogenetic reconstruction (MrBayes v3.2.7) of relationships among Cambarus lapidosus, C. burchfielae, and other related and outgroup taxa using the COI mtDNA barcoding region. Numbers at nodes indicate posterior probabilities (pp); probabilities>99% are denoted by an asterisk (*). Letters correspond to clades discussed in the text. Scale bar represents estimated number of nucleotide substitutions per site.

FIGURE 6 in Integrative taxonomy reveals two new narrowly-endemic crayfish species (Decapoda: Cambaridae) from the Yadkin River Basin in western North Carolina, USA

FIGURE 6. Stony Fork, facing south near the type locality of Cambarus lapidosus, in Watauga County, NC—25 October 2019 (photo credit: Michael A. Perkins, NCWRC).

FIGURE 1 in Integrative taxonomy reveals two new narrowly-endemic crayfish species (Decapoda: Cambaridae) from the Yadkin River Basin in western North Carolina, USA

FIGURE 1. Terrain map of collection sites and the known ranges of Cambarus lapidosus and C. burchfielae in the Blue Ridge mountains of western North Carolina. Red triangles represent genetic samples and specimens of C. lapidosus used in this study; the red star indicates the type locality and red shading represents the known range (one HUC12) of the species. Orange diamonds represent genetic samples and specimens of C. burchfielae used in this study; the orange star indicates the type locality and orange shading represents the known range (two HUC12s) of the species. Open circles indicate genetic sampling locations where neither focal species was detected during this study. Closed circles represent historic sampling locations (combined NCSM and NCWRC records) where specimens of the target species were not identified. Black lines represent major drainage boundaries (HUC6), pink-bordered line indicates the Eastern Continental Divide. Green shading represents conserved or protected lands, dark-gray shading represents developed areas. Inset: the boundaries of North Carolina's major river basins and bordering states; gray shading denotes the Yadkin-PeeDee basin. (Maps created in QGIS v3.1.2).

FIGURE 10 in Integrative taxonomy reveals two new narrowly-endemic crayfish species (Decapoda: Cambaridae) from the Yadkin River Basin in western North Carolina, USA

FIGURE 10. Fall Creek, facing south near the type locality of Cambarus burchfielae, in Wilkes County, NC—29 October 2021 (photo credit: Michael A. Perkins, NCWRC)