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| Latrodectus lucacha Miller, Kratzer & Griswold, 2026 |
Abstract
We describe a new species of widow spider (Araneae, Theridiidae, Latrodectus) from the Andean region. DNA barcode sequences are provided. The species is documented from museum specimens across Peru and identified from photographs on iNaturalist, extending its inferred distribution into Ecuador, Bolivia, and Chile. We integrate specimen and citizen-science occurrences to generate a species distribution model using WorldClim bioclimatic variables, predicting highest suitability along temperate to high-elevation Andean regions. We discuss the utility and limitations of citizen-science imagery for delimiting and mapping species and summarize available information on clinical aspects of envenomation in Peru associated with the local “lucacha” widow spider.
Key words: Andes, citizen-science, DNA barcode, iNaturalist, Latrodectus lucacha, new species, Peru, species distribution model, taxonomy
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| Observations of Latrodectus lucacha Miller, Kratzer & Griswold, sp. nov., from iNaturalist. A. Female, male and egg case, from Arica, Arica y Parinacota, Chile; iNaturalist.org (by ferru, CC-BY-NC); B. Female with two egg cases, note parasitoid wasps on egg case, from Nabón, Azuay, Ecuador; iNaturalist.org (by kabirbosques, CC-BY); C. Female feeding on a beetle, from Lima, Peru; iNaturalist.org (by ruthgo, CC0); D. Female feeding on a damselfly, from Lima, Peru; iNaturalist.org (by Mathieu_fr, CC-BY-NC). |
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| Latrodectus lucacha Miller, Kratzer & Griswold, sp. nov. A–C. From Pantanos de Villa Om, Lima, Peru (MUSM-ENT 051958), microphotographs of adult male; D. From Pachacayo, Junin, Peru (MUSM-ENT 0519569), schematic illustration of female reproductive structures; A, D. Dorsal; B. Lateral; C. Ventral. Abbreviations: CD copulatory duct, FD Fertilization duct, SP Spermathecae. Scale bars: 1.0 mm (A–C), 0.5 mm (D). |
Latrodectus lucacha Miller, Kratzer & Griswold, sp. nov.
Diagnosis. Female with three loop copulatory ducts (Figs 2D, 3D–F), distinguishing it from L. geometricus C. L. Koch, 1841 and L. quartus Abalos, 1980 (Abalos 1980: figs 39, 66), which have more loops (ca 4), and from L. antheratus (Badcock, 1932) and L. variegatus Nicolet, 1849 (Abalos 1980: figs 49, 58), which have fewer (2). With dorsal longitudinal opisthosomal stripe variable in both width and length (Figs 4, 5), resembling several South American species, but not exhibiting oblique vertical stripes on the posterior quarter ...
Etymology. Lucacha is a common name for widow spiders in Peru (Pickard-Cambridge 1902; Maguiña Vargas et al. 2017).
Jeremy Miller, Chris Alice Kratzer and Charles Griswold. 2026. Description of A New Andean Species of Widow Spider (Araneae, Theridiidae, Latrodectus). ZooKeys. 1281: 49-67. DOI: doi.org/10.3897/zookeys.1281.185973
