Conservation of threatened animals is frequently limited by lack of knowledge about their ecological preferences, and often artificial feeding is one of the few chances to save endangered species. We investigated the possibility to artificially feed two endangered flat bark beetles dependent on dead wood for their diet-namely, Cucujus cinnaberinus (Scopoli, 1763) and Cucujus haematodes Erichson, 1845-by examining their dietary preferences, life cycle duration, and survival in laboratory conditions. Individuals of the two species were caught in the wild and larvae and adults were fed in laboratory conditions by live or dead prey. Three species of saproxylic beetles: two cerambycids (Acanthocinus griseus Fabricius, 1793 and Rhagium inquisitor Linnaeus, 1758), one scolytid (Ips sexdentatus Börner, 1776) one tenebrionid (Tenebrio molitor (Linnaeus, 1758)) one dipteran (Lucilia sericata (Meigen, 1826)) and one ant (Lasius sp. Fabricius, 1804) were used as prey, with minced meat as a control. Our results indicated high survival and no difference in prey choice between the two flat beetle species. Larvae and adults preferred dead prey, but no significant preference was detected among dead prey taxa, supporting the hypothesis that the two species are opportunistic scavengers. Comparing data with previous results, both species and their developmental stages should be classified as obligate saproxylic organisms with preference to the dead and decaying organic material. Successful artificial feeding and rearing of these endangered species, followed by the release in the wild through rescue or reintroduction programs, therefore appear relevant for their protection and future conservation.

Department of Biology Faculty of Science University of Hradec Králové Hradec Králové Czech Republic

Department of Forest Protection and Entomology Faculty of Forestry and Wood Sciences Czech University of Life Sciences Prague Praha Czech Republic

Dipartimento di Biologia Ecologia e Scienze della Terra University of Calabria Rende Italy

See more in PubMed

Alexander K N. 2008. Tree biology and saproxylic Coleoptera: issues of definitions and conservation language. Rev. Ecol. 10: 9–13.

Anderson J, and Nilssen A C. . 1978. The food selection of Pytho depressus L. (Col., Pythidae). Norw. J. Entomol. 25: 225–226.

Arnett R H. 1968. The beetles of the United States: a manual for identification. The American Entomological Institute, Ann Arbor, MI.

Bełcik M, Goczał J, and Ciach M. . 2019. Large-scale habitat model reveals a key role of large trees and protected areas in the metapopulation survival of the saproxylic specialist Cucujus cinnaberinus. Biodivers. Conserv. 28: 3851–3871.

Bonacci T, Mazzei A, Horák J, and Brandmayr P. . 2012. Cucujus tulliae sp. n.—an endemic Mediterranean saproxylic beetle from genus Cucujus Fabricius, 1775 (Coleoptera, Cucujidae), and keys for identification of adults and larvae native to Europe (2012). ZooKeys  212: 63–79. PubMed PMC

Bonacci T, Mazzei A, Naccarato A, Elliani R, Tagarelli A, and Brandmayr P. . 2018. Beetles ‘in red’: are the endangered flat bark beetles Cucujus cinnaberinus and C. haematodes chemically protected? (Coleoptera: Cucujidae). Eur. Zool. J. 85: 129–137.

Borror D J, and White R E. . 1970. A field guide to insects. America North of Mexico. Houghton Mifflin Harcourt, Boston, MA.

Borror D J, Delong D M, and Triplehorn C A. . 1976. An introduction to the study of insects. Holt, Rinehart and Winston, New York, NY.

Cálix M, Alexander K N A, Nieto A, Dodelin B, Soldati F, Telnov D, Vazquez-Albalate X, Aleksandrowicz O, Audisio P, Istrate P, . et al. 2018. European red list of saproxylic beetles. IUCN, Brussels, Belgium.

Cock M J W. 1978. The assessment of preference. J. Anim. Ecol. 47: 805–816.

Conway W. 1995. Wild and zoo animal interactive management and habitat conservation. Biodivers. Conserv. 4: 573–594.

Della Rocca F, and Milanesi P. . 2020. Combining climate, land use change and dispersal to predict the distribution of endangered species with limited vagility. J. Biogeogr. 47: 1427–1438.

Essig E O. 1926. Insects of Western North America. Macmillan, New York, NY.

Grove S J. 2002. Saproxylic insect ecology and the sustainable management of forests. Annu. Rev. Ecol. Syst. 33: 1–23.

Gutowski J M, Kadej M, Smolis A, and Tarnawski D. . 2014. Identification of larvae of endangered Cucujus cinnaberinus and C. haematodes (Coleoptera: Cucujidae). J. Insect Sci. 14(228): 1–7. PubMed PMC

Hilszczański J, Jaworski T, Plewa R, and Jansson N. . 2014. Surrogate tree cavities: boxes with artificial substrate can serve as temporary habitat for Osmoderma barnabita (Motsch.) (Coleoptera, Cetoniinae). J. Insect Conserv. 18: 855–861.

Horák J. 2011. Contribution to knowledge of diet preferences of the endangered saproxylic beetle Cucujus cinnaberinus (Coleoptera: Cucujidae) from East Bohemia. Acta Mus. Reg. Ser A. 33: 127–130.

Horák J. 2015. What is happening after an abiotic disturbance? Response of saproxylic beetles in the Primorsky Region woodlands (Far Eastern Russia). J. Insect Conserv. 19: 97–103.

Horák J. 2018. The role of urban environments for saproxylic insects. In  Ulyshen M D, (ed.), Saproxylic insects. Springer, Cham, Germany.

Horák J, and Chobot K. . 2009. Worldwide distribution of saproxylic beetles of the genus Cucujus Fabricius, 1775 (Coleoptera: Cucujidae), pp. 189–206. In  Buse J K N A, Alexander T., Ranius T and Assmann T (eds.), Saproxylic beetles, their role and diversity in European woodland and tree habitats. Pensoft Publishers, Sofia-Moscow, RU.

Horák J, and Chobot K. . 2011. Phenology and notes on the behaviour of Cucujus cinnaberinus: points for understanding the conservation of the saproxylic beetle. North-West. J. Zool. 7: 352–355.

Horák J, Zaitsev A A, and Vávrová E. . 2011. Ecological requirements of a rare saproxylic beetle Cucujus haematodes (Coleoptera: Cucujidae)—the beetles’ stronghold on the edge of its distribution area. Insect Conserv. Diver. 4: 81–88.

Horák J, Chobot K, and Horáková J. . 2012a. Hanging on by the tips of the tarsi: review of the plight of critically endangered saproxylic beetle in European forests. J. Nat. Conserv. 20: 101–108.

Horák J, Chumanová E, and Hilszczański J. . 2012b. Saproxylic beetle thrives on the openness in management: a case study on the ecological requirements of Cucujus cinnaberinus from Central Europe. Insect Conserv. Divers. 5: 403–413.

Hsiao Y. 2020. A taxonomic study of Cucujus Fabricius, 1775 from Asia (Coleoptera: Cucujidae), with descriptions of new species and notes on morphological classification. Insect Syst. Evol. 51: 1–51.

Inoda T, Hasegawa M, Kamimura S, and Hori M. . 2009. Dietary program for rearing the larvae of a diving beetle, Dytiscus sharpi (Wehncke), in the laboratory (Coleoptera: Dytiscidae). Coleopts. Bull. 63: 340–350.

Jaworski T, Plewa R, Tarwacki G, Sućko K, Hilszczański J, and Horák J. . 2019. Ecologically similar saproxylic beetles depend on diversified deadwood resources: from habitat requirements to management implications. Forest Ecol. Manag. 449: 117462.

Kolter L, and Zimmermann W. . 1988. Social behaviour of Przewalski horses (Equus p. przewalskii) in the Cologne Zoo and its consequences for management and housing. Appl. Anim. Behav. Sci. 21: 117–145.

Lawrence J F. 1991. Order Coleoptera (general discussion, family key, various family treatments), pp. 144–658. In  Stehr F W, (ed.) Immature insects. Vol. 2 Kendall/Hunt, Dubuque, Iowa.

Lee C F, and Putz A. . 2008. A new species of Cucujus Fabricius, 1775 from China and key to the east-Palaearctic species of the genus (Coleoptera: Cucujidae). Entomol. Z. 118: 211–213.

Mamaev B M, Krivosheina N P, and Pototskaia V A. . 1977. Opredelitel’ lichinok khishchnykh nasekomykh entomofagov stvolovykh vrediteley. Izdatel’stvo Nauka, Moskva, 392 pp (in Russian).

Manly B F J. 1974. A model for certain types of selection experiments. Biometrics  30: 281–294.

Mazzei A, Bonacci T, Contarini E, Zetto T, and Brandmayr. P. 2011. Rediscovering the “umbrella species” candidate Cucujus cinnaberinus (Scopoli, 1763) in southern Italy (Coleoptera Cucujidae), and notes on bionomy. Ital. J. Zool. 78: 264–270.

Mazzei A, Bonacci T, Horák J, and Brandmayr P. . 2018. The role of topography, stand and habitat features for management and biodiversity of a prominent forest hotspot of the Mediterranean Basin: Saproxylic beetles as possible indicators. Forest Ecol. Manag. 410: 66–75.

Nieto A, and Alexander K N A. . 2010. European red list of saproxylic beetles. Publications Office of the European Union, Luxembourg.

Palm T. 1941. Über die Entwicklung und Lebensweise einiger wenig bekannten Käfer-Arten im Urwaldgebiet am Fluss Dalälven (Schweden) II und III. Opusc. Entomol. 6: 17–26.

Peterson A. 1951. Larvae of insects. An introduction to nearctic species. Part II. Alvah Peterson, Columbus, OH.

Přikryl Z B, Turčáni M, and Horák J. . 2012. Sharing the same space: foraging behaviour of saproxylic beetles in relation to diet components of their morphologically similar larvae. Ecol. Entomol. 37: 117–123.

Sformo T, Walters K  Jeannet K  Wowk B  Fahy G M  Barnes B M and Duman J G. . 2010. Deep supercooling, vitrification and limited survival to–100 C in the Alaskan beetle Cucujus clavipes puniceus (Coleoptera: Cucujidae) larvae. J Exp. Biol. 213: 502–509. PubMed

Sherratt T S, and Harvey I. . 1993. Frequency- dependent food selection by arthropods: a review. Biol. J. Linn. Soc. 48: 167–186.

Ślipiński S. 1982. Klucze do Oznaczania Owadów Polski, Coleoptera-Cucujidae. Państwowe Wydawnictwo Naukowe, Warszawa-Wroclaw, Poland.

Smith D B, and Sears M K. . 1982. Mandibular structure and feeding habits of three morphologically similar coleopterous larvae: Cucujus clavipes (Cucujidae), Dendroides canadensis (Pyrochroidae), and Pytho depressus (Salpingidae). Can. Entomol. 114: 173–175.

Straka U. 2017. Beobachtungen zur Imaginalbiologie des Scharlachkäfers Cucujus cinnaberinus (Scopoli, 1763) (Coleoptera: Cucujidae). Beitr. Entom. 18: 109–116.

Swan L A, and Papp C S. . 1972. The common insects of North America. Harper and Row, New York, NY.

Yi D A, Kuprin A V, Lee Y H, and Bae Y J. . 2017. Newly developed fungal diet for artificial rearing of the endangered long-horned beetle Callipogon relictus (Coleoptera: Cerambycidae). Entomol. Res. 47: 373–379.

Niche partitioning among dead wood-dependent beetles

From Phenology and Habitat Preferences to Climate Change: Importance of Citizen Science in Studying Insect Ecology in the Continental Scale with American Red Flat Bark Beetle, Cucujus clavipes, as a Model Species