Dataset Information

A micro X-ray computed tomography dataset of South African hermit crabs (Crustacea: Decapoda: Anomura: Paguroidea) containing scans of two rare specimens and three recently described species.

ABSTRACT: Background:Along with the conventional deposition of physical types at natural history museums, the deposition of 3-dimensional (3D) image data has been proposed for rare and valuable museum specimens, such as irreplaceable type material. Findings:Micro computed tomography (?CT) scan data of 5 hermit crab species from South Africa, including rare specimens and type material, depicted main identification characteristics of calcified body parts. However, low-image contrasts, especially in larger (>50 mm total length) specimens, did not allow sufficient 3D reconstructions of weakly calcified and fine characteristics, such as soft tissue of the pleon, mouthparts, gills, and setation. Reconstructions of soft tissue were sometimes possible, depending on individual sample and scanning characteristics. The raw data of seven scans are publicly available for download from the GigaDB repository. Conclusions:Calcified body parts visualized from ?CT data can aid taxonomic validation and provide additional, virtual deposition of rare specimens. The use of a nondestructive, nonstaining ?CT approach for taxonomy, reconstructions of soft tissue structures, microscopic spines, and setae depend on species characteristics. Constrained to these limitations, the presented dataset can be used for future morphological studies. However, our virtual specimens will be most valuable to taxonomists who can download a digital avatar for 3D examination. Simultaneously, in the event of physical damage to or loss of the original physical specimen, this dataset serves as a vital insurance policy.

SUBMITTER: Landschoff J

PROVIDER: S-EPMC5890486 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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A micro X-ray computed tomography dataset of South African hermit crabs (Crustacea: Decapoda: Anomura: Paguroidea) containing scans of two rare specimens and three recently described species.

Landschoff Jannes J Du Plessis Anton A Griffiths Charles L CL

GigaScience 20180401 4

<h4>Background</h4>Along with the conventional deposition of physical types at natural history museums, the deposition of 3-dimensional (3D) image data has been proposed for rare and valuable museum specimens, such as irreplaceable type material.<h4>Findings</h4>Micro computed tomography (μCT) scan data of 5 hermit crab species from South Africa, including rare specimens and type material, depicted main identification characteristics of calcified body parts. However, low-image contrasts, especia ...[more]

PMID: 29635298

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Project description:Deep-water hermit crabs of the family Parapaguridae can be abundant (up to 20 kg or 1000 hermit crab individuals per haul) in the trawl bycatch collected during South African demersal abundance research surveys. Until recently, only two parapagurid species had been recognized in the bycatch; Parapagurus bouvieri Stebbing, 1910, and Sympagurus dimorphus (Studer, 1883). Detailed examination of numerous samples of parapagurid specimens from research surveys revealed the existence of a third, undescribed species previously confounded with S. dimorphus, but in fact belonging to a different genus. This new species, Paragiopagurus atkinsonaesp. n. is the 25th in the genus Paragiopagurus Lemaitre, 1996, and has been found only in a small region on the West Coast shelf of South Africa, at depths of 199-277 m. The species is herein fully described and illustrated, including colour images, µCT scans of selected body parts, and CO1 barcode data. The new species is morphologically most similar to P. ventilatus Lemaitre, 2004, a species associated with hydrothermal vents, but differs in armature of the fourth antennal segment (armed with a spine on the dorsolateral distal angle vs. unarmed in P. ventilatus); setation of the antennal flagella (nearly naked vs. with dense setae in P. ventilatus); plumose setation on the third maxillipeds and basal segments of chelipeds (absent vs. present in P. ventilatus); number of rows of scales on the propodal rasp of pereopod 4 (two or three rows vs. one row in P. ventilatus); and degree of telson asymmetry (weakly asymmetrical vs. strongly asymmetrical in P. ventilatus). Paragiopagurus atkinsonaesp. n. is superficially similar to S. dimorphus, with males of the two species showing the same extreme degree of sexual dimorphism on the right cheliped, general light orange colouration, and frequent use of colonial zoanthid carcinoecia for pleonal protection. To aid in future identifications and to facilitate data gathering during surveys, a comparison of P. atkinsonaesp. n. with S. dimorphus is provided, along with descriptions of colouration and photographs of live specimens of all three parapagurid species. Information on taxonomy of the species is summarized, as well as knowledge of their distribution in the demersal research survey regions of South Africa.

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Dataset Information

A micro X-ray computed tomography dataset of South African hermit crabs (Crustacea: Decapoda: Anomura: Paguroidea) containing scans of two rare specimens and three recently described species.

Publications

A micro X-ray computed tomography dataset of South African hermit crabs (Crustacea: Decapoda: Anomura: Paguroidea) containing scans of two rare specimens and three recently described species.

Similar Datasets

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