Shchapova E.P.1,2, Rzhechitskiy Y.A.1, Kaluzhnaya O.V.1, Titov E.A.3, Khanaev I.V.4, Vereshchagina K.P.1, Timofeyev M.A.1, Gurkov A.N.1* 2026. Anatomy of endemic amphipods (Crustacea: Amphipoda) from Lake Baikal in light of implanting optical sensors // Invert. Zool. Vol.23. No.1: 100–113 [in English].
1 Institute of Lake Baikal Biology, Irkutsk State University, Lenin st. 3, Irkutsk 664025 Russia.
2 Baikal Research Centre, Rabochaya st. 5v, Irkutsk 664003 Russia.
3 East-Siberian Institute of Medical and Ecological Research, Mikrorayon 12a 3, Angarsk 665827 Russia.
4 Limnological Institute of the Siberian Branch of the Russian Academy of Sciences, Ulan-Batorskaya st. 3, Irkutsk 664033 Russia.
* Corresponding author
Ekaterina Shchapova: shchapova.katerina@gmail.com https://orcid.org/0000-0001-9084-7675
Yaroslav Rzhechitskiy: rzhechitskiy.yar@gmail.com https://orcid.org/0000-0001-8603-572X
Olga Kaluzhnaya: olgavk101010@gmail.com https://orcid.org/0000-0002-3845-6375
Evgeniy Titov: evgtitov83@gmail.com https://orcid.org/0000-0002-0665-8060
Igor Khanaev: igkhan@lin.irk.ru https://orcid.org/0000-0001-6431-2765
Kseniya Vereshchagina: k.p.vereshagina@gmail.com https://orcid.org/0000-0002-4843-5287
Maxim Timofeyev: m.a.timofeyev@gmail.com https://orcid.org/0000-0002-5250-6818
Anton Gurkov: a.n.gurkov@gmail.com https://orcid.org/0000-0002-8390-1570
doi: 10.15298/invertzool.23.1.06
ABSTRACT: Implantable devices for continuous release or sensing of specific substances inside animal tissues have the potential to facilitate automatization of research on a multitude of species. However, injection of implants requires understanding of the species anatomies in order to ensure a proper contact with the chosen tissues and prevent damage of internal organs. Here, we dive into the unclear aspects of the anatomy of amphipods (Crustacea: Amphipoda), one of the most important groups of crustaceans, on the example of morphologically diverse endemic amphipods from Lake Baikal. In particular, we searched for large lacunae in frozen sections of a relatively small shallow-water amphipod (~3 cm long) and tested the applicability of optical sensors close to the body surface of larger deeper-dwelling species (over 6 cm long) with outgrowths of exoskeleton. Apical muscles were found to be the most universal site for application of implantable optical sensors not only in smaller species but also in larger amphipods. For the cases when the implants should have direct contact with animal hemolymph, we identified a suitable large lacuna in the segments 9-10 on the example of a shallow-water Eulimnogammarus verrucosus. As a by-product, we found dorsal carinae of the largest Baikal amphipods of the genus Acanthogammarus to contain a significant amount of adipose-like tissue.
KEY WORDS: autofluorescence; Baikal; crustaceans; cryotomy; deep-water; implantable sensors.