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Species Thermonectus marmoratus - Sunburst Diving Beetle

Sunburst Diving Beetle - Thermonectus marmoratus Sunburst Diving Beetles - Thermonectus marmoratus Arizona Beetle - Thermonectus marmoratus Spotted Beetle - Thermonectus marmoratus Thermonectus marmoratus Arizona Beetle  - Thermonectus marmoratus Sunburst diving beetle? - Thermonectus marmoratus Sunburst diving beetle? - Thermonectus marmoratus
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Adephaga
Family Dytiscidae (Predaceous Diving Beetles)
Subfamily Dytiscinae
Tribe Aciliini
Genus Thermonectus
Species marmoratus (Sunburst Diving Beetle)
Synonyms and other taxonomic changes
Thermonectus marmoratus (Gray)
Orig. Comb: Hydaticus marmoratus Gray, 1832 (Nilsson 2001)
Syn: Thermonetus, Thermonectes (spelling)
Syn: Acilius maculatus LeConte, 1854
Explanation of Names
marmoratus (G). 'marble; sparkle, glisten' (1)
11.4 to 14.0 mm (2)
s. CA to c. TX / s. Mex. - Map (2)(3)(4)
Prefers pool habitats in temporary or intermittent streams (Velasco and Millan 1998)
Eats dead organisms found on the surface film or the bottom, engulfing small items and chewing large ones (Velasco and Millan 1998)
Ejects a milky fluid from its prothoracic defensive glands when disturbed, containing a mixture of steroid compounds, presumably as a deterrent to fish predators (Meinwald et al. 1998). The main steroid compound in the defensive secretion is a novel compound called "Mirasorvone"; named for the actress Mira Sorvino, who "as Dr. Susan Tyler in the motion picture Mimic, successfully confronted the ultimate insect challenge" (Meinwald et al. 1998)
Print References
Meinwald, J., Q. Huang, J. Vrkoč, K.B. Herath, Z-C. Yang, F. Schröder, A.B. Attygalle, V.K. Iyengar, R.C. Morgan, and T. Eisner 1998. Mirasorvone: A masked 20-ketopregnane from the defensive secretion of a diving beetle (Thermonectus marmoratus). Proc Natl Acad Sci. 95(6): 2733–2737.
Morgan, R.C. 1992a. Natural History, Captive Management and Display of the Sunburst Diving Beetle Thermonectus marmoratus. AAZPA/CAZPA Annual Conference Proceedings. pp. 457-464.
Morgan, R.C. 1992b. Culture Corner: Sunburst Diving Beetles: Living Jewels Brighten Rippling Waters. Backyard BUGwatching. 14: 4-10.
Morgan R.C. 1995. Invertebrates in Captivity Conference Proceedings. Sonoran Arthropod Studies Institute, Tucson, AZ. pp. 50–57.
Morgan, R.C. 1998. Windows on the Water World. Backyard BUGwatching Special Issue #1. pp. 4-6.
Nilsson, A.N. 2001. World Catalogue of Insects. Vol. 3: Dytiscidae (Coleoptera). Apollo Books. Stenstrup, Denmark. 395 pp. Full Text
Salvatore, D. & R.C. Morgan. 1992. Take A Closer Look: Sunburst Diving Beetle. Backyard BUGwatching. 14: 10.
Velasco, J. and A. Millan. 1998. Feedings habits of two large insects from a desert stream: Abedus herberti (Hemiptera: Belostomatidae) and Thermonectus marmoratus (Coleoptera: Dytiscidae). Aquatic Insects 20(2): 85-96.
Internet References
LeConte's Type - MCZ, Harvard
Works Cited
1.Dictionary of Word Roots and Combining Forms
Donald J. Borror. 1960. Mayfield Publishing Company.
2.Predaceous Diving Beetles (Coleoptera: Dytiscidae) of the Nearctic Region, with emphasis on the fauna of Canada and Alaska
D.J. Larson, Y. Alarie, and R.E. Roughley. 2001. NRC 43253.
3.Biotic Resources of Indio Mountains Research Station: Southeastern Hudspeth County, Texas.
Worthington, R.D., C. Lieb and W. Anderson. 2010. Authors, El Paso, Texas. 85 pp.
4.Global Biodiversity Information Facility (GBIF)