Jump to content

Cybister

From Wikipedia, the free encyclopedia

Cybister
Cybister fimbriolatus
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Family: Dytiscidae
Subfamily: Cybistrinae
Tribe: Cybistrini
Genus: Cybister
Curtis, 1827
Cybister lateralimarginalis
Comparison of Cybister and Dytiscus larvae

Cybister ('kybistētēr' = diver, tumbler), is a genus of beetle in family Dytiscidae. They are found in much of the world, including all continents except Antarctica.[1][2] As of 2021 there are 96 species and 9 additional subspecies among four subgenera in the genus.[3]

Description

[edit]

Adult Cybister have broad hind legs with unequal tarsal claws (the inner claw being smaller and sometimes absent) and a fringe on the outer margin of the tarsus.[4] They range in length up to 43 mm (C. bimaculatus from the Afrotropics).[5] Adult males of the North American species have several ridges on the coxae of the hind legs, forming a stridulatory device.[5]

Larvae have a frontal tooth on the head and lack cerci. North American species can grow up to 80 mm long.[4]

Ecology

[edit]

Cybister live in lentic (still fresh water) habitats that have vegetation.[6]

Like other diving beetles, Cybister are predatory. Larvae of C. japonicus prey on insects (mainly Odonata nymphs and the backswimmer Notonecta triguttata) in their first two instars, while third-instar larvae prey on vertebrates (tadpoles and fish).[7] Larvae of C. rugosus feed on both invertebrates and vertebrates in all instars.[8]

Importance

[edit]

Cybister chinensis (sometimes misidentified as C. japonicus) is used in a game in Korea. The water beetle game (mul bang gae nori) is played in an oval, water-filled tank with vertical flanges along its inner edge and prizes on the tank rim. The game is played by dropping a C. chinensis through a funnel into the center of the tank, after which it swims towards the edge of the tank and stops in one of the slots formed by the metal flanges. If a prize is above this slot, the player wins it.[9]

The swimming behaviour of C. lateralimarginalis has inspired (biomimetics) the design of a legged underwater robot.[10]

List of species

[edit]

Subgenus Cybister Curtis, 1827

[edit]

Subgenus Megadytoides Brinck, 1945

[edit]

Subgenus Melanectes Brinck, 1945

[edit]

Subgenus Neocybister K.B. Miller, Bergsten & Whiting, 2007

[edit]

Fossil species

[edit]

These seven extinct species are known only from fossils:

References

[edit]
  1. ^ Miller, K.B.; J. Bergsten (2016). Diving Beetles of the World: Systematics and Biology of the Dytiscidae. JHU Press. pp. 131–132. ISBN 978-1-4214-2054-7.
  2. ^ Roberts, C H (1905). "The Distinctive Characters of the Eastern Species of the Genera Dytiscus and Cybister". Journal of the New York Entomological Society. 13: 103–107.
  3. ^ Nilsson, Anders N.; Hájek, Jiří (2021). "A World Catalogue of the Family Dytiscidae or the Diving Beetles (Coleoptera, Adephaga)" (PDF) (1.I.2021 ed.).
  4. ^ a b "Genus Cybister". bugguide.net. Retrieved 2023-03-02.
  5. ^ a b Arce-Pérez, Roberto; Novelo-Gutiérrez, Rodolfo; Fery, Hans (2021-11-04). "Cybister (s. str.) poblanus sp. n. from Mexico and notes on other species of Cybistrinae (Coleoptera: Dytiscidae)". Zootaxa. 5061 (2): 323–339. doi:10.11646/zootaxa.5061.2.5. ISSN 1175-5334. PMID 34810625.
  6. ^ Liao, Wenfei (2018-08-19). "Cybister, an Immigrant in Finland". Wenfei's Blog. Retrieved 2023-03-02.
  7. ^ Ohba, Shin-Ya (2009-06-01). "Ontogenetic Dietary Shift in the Larvae of Cybister japonicus (Coleoptera: Dytiscidae) in Japanese Rice Fields". Environmental Entomology. 38 (3): 856–860. doi:10.1603/022.038.0339. ISSN 0046-225X. PMID 19508796.
  8. ^ Yamasaki, Shun; Watanabe, Kohei; Ohba, Shin-ya (2022). "Larval feeding habits of the large-bodied diving beetle Cybister rugosus (Coleoptera: Dytiscidae) under laboratory conditions". Entomological Science. 25 (2). doi:10.1111/ens.12510. ISSN 1343-8786.
  9. ^ Pemberton, R. W. (1990). "The Korean water beetle game". Pan-Pacific Entomologist. 66 (2): 172–174.
  10. ^ Kim, Heejoong; Lee, Jihong (2017). "Design, swimming motion planning and implementation of a legged underwater robot (CALEB10: D.BeeBot) by biomimetic approach". Ocean Engineering. 130: 310–327. doi:10.1016/j.oceaneng.2016.11.006.
[edit]
  • Media related to Cybister at Wikimedia Commons
  • Data related to Cybister at Wikispecies