2026-10-06T13:39:41Z https://api.figshare.com/v2/oai

oai:figshare.com:article/33870931 2026-09-17T04:48:40Z category_24430 category_25900 item_type_3 month_year_09_2026

Paired Appendage Microgeometry and Used-Substrate Images of a Small Burrowing Cirolanid Isopod from Akita, Japan Osuke Doijiri (24913549) Animal structure and function Biological oceanography Cirolanidae Isopoda Crustacea appendage morphology substrate grain size burrowing morphometrics image analysis swash zone Akita Japan <p dir="ltr">This dataset accompanies a technical-note study introducing an image-based approach for comparing appendage microgeometry with the grain size of substrate used by a small burrowing crustacean.</p><p dir="ltr">The dataset is based on a single approximately 5-mm cirolanid isopod collected from a sandy swash-zone habitat on the Japan Sea coast of Akita Prefecture, Japan. The specimen was maintained for approximately one month with sand originating from the collection site and was frequently observed burrowing into the substrate. The working taxonomic identification is <i>Cirolanidae</i> sp. cf. <i>Excirolana chiltoni</i>; species-level identification remains provisional.</p><p dir="ltr">The archive contains original photographs of the specimen and its appendages, microscope images of the associated substrate, derived image measurements, metadata, a data dictionary, a file manifest, and Python code for reproducing the principal quantitative results.</p><p dir="ltr">The technical approach uses images obtained at the same optical magnification and dimensionless normalization to compare appendage protrusion length with substrate grain diameter. Candidate protrusions were conservatively detected from multiple appendage images, and cross-image recurrence was used to identify repeatedly observed morphological features. A substrate grain-size reference was derived from the corresponding microscope images. The principal scale-matching metric is defined as the ratio of appendage protrusion length to substrate median grain diameter (D50).</p><p dir="ltr">Across five appendage photographs, 42 conservative protrusion candidates were detected. Cross-image recurrence filtering identified eight consensus features, four of which were observed in at least three images. The median consensus protrusion-length/D50 ratio was 1.5708, with individual consensus values ranging from 0.780 to 3.298.</p><p dir="ltr">These measurements represent a methodological demonstration based on one biological individual. Repeated images and individual protrusions are not independent biological replicates. The detected protrusions should not automatically be interpreted as homologous anatomical spines or setae, and the observed scale correspondence does not by itself demonstrate adaptation or establish a general relationship between appendage morphology and sediment grain size.</p><p dir="ltr">The dataset is intended to support reproducibility, methodological development, and future validation using additional specimens and independently characterized substrates.</p><p dir="ltr"><b>Acknowledgments:</b> The author sincerely thanks Chisa Doijiri for maintaining the specimen during captivity and for kindly donating it for this study.</p> 2026-09-17T04:48:40Z Dataset Dataset 10.6084/m9.figshare.33870931.v1 https://figshare.com/articles/dataset/Paired_Appendage_Microgeometry_and_Used-Substrate_Images_of_a_Small_Burrowing_Cirolanid_Isopod_from_Akita_Japan/33870931 CC BY 4.0