Cucujus

Abstract: Larvae of the freeze-avoiding beetle Cucujus clavipes puniceus (Coleoptera: Cucujidae) in Alaska have mean supercooling points in winter of -35 to -42 degrees C, with the lowest supercooling point recorded for an individual of -58 degrees C. We previously noted that some larvae did not freeze when cooled to -80 degrees C, and we speculated that these larvae vitrified. Here we present evidence through differential scanning calorimetry that C. c. puniceus larvae transition into a glass-like state at temperatures<-58 degrees C and can avoid freezing to at least -150 degrees C. This novel finding adds vitrification to the list of insect overwintering strategies. While overwintering beneath the bark of fallen trees, C. c. puniceus larvae may experience low ambient temperatures of around -40 degrees C (and lower) when microhabitat is un-insulated because of low snow cover. Decreasing temperatures in winter are correlated with loss of body water from summer high levels near 2.0 to winter lows near 0.4 mg mg(-1) dry mass and concomitant increases in glycerol concentrations (4-6 mol l(-1)) and thermal hysteresis. Finally, we provide direct evidence that Cucujus from Wiseman, Alaska, survive temperatures to -100 degrees C.

Abstract: Cucujus tulliae sp. n. is described as a new member of genus Cucujus Fabricius, 1775 (Coleoptera, Cucujidae), which enumerates at present eleven species distributed in Eurasia and northern America. This saproxylic beetle is the first Cucujus species known only from Mediterranean and it is probably endemic to Calabria (Italy). The species was found especially in old–growth mountain forests of high conservation value (i.e. national parks) dominated by Calabrian pine (Pinus laricio calabrica). We hypothesize that Cucujus tulliae sp. n. probably evolved from isolated populations of Cucujus haematodes Erichson, 1845. The species is thus relictual and of high conservation value, corresponding at least to endangered (EN) category with respect to recent IUCN criterion. Cucujus tulliae sp. n. is here compared with two species native to Europe – Cucujus haematodes and Cucujus cinnaberinus (Scopoli, 1763) and with the Caucasian Cucujus haematodes caucasicus Motschulsky, 1845, which is confirmed as a valid subspecies. The male genitalia of this Caucasian form have been examined and illustrated for the first time. A comprehensive key to adults and larvae of European species is provided.

Abstract: Larvae of Cucujus clavipes (Fabricius) and Dendroides canadensis (Latreille) are frequently found under bark of decaying hardwood logs and those of Pytho depressus (Linnaeus) under that of dead conifers, especially pine (Pinus spp.) (Anderson and Nilssen 1978). Larvae of all three species have a dorsoventrally depressed, orthosomatic body and are well adapted for activity in the cambial layer. In dead trees, this area contains partially decomposed wood and bark resulting from the activity of phytophagous insects and other small invertebrates. According to textbooks of general entomology and other entomological literature, species within the genera Cucujus, Dendroides, and Pytho are predacious on other insects found in the cambial layer (Arnett 1968; Borrer et al. 1976; Borror and White 1970; Essig 1926; Peterson 1951; Swan and Papp 1972). However, no specific references to original studies demonstrating this type of feeding behaviour could be found. The purpose of this study was to determine the type of food consumed by larvae of these species and to determine if the structure of their mandibles and other mouthparts were indicative of such food consumption.

Abstract: A review of the genus Cucujus Fabricius (Insecta: Cucujoidea: Cucujidae) from Taiwan, Japan, and China, with descriptions of two new species and the larvae of Cucujus mniszechi Grouvelle. Zoological Studies 46(3): 311-321. Species of the genus Cucujus from Taiwan, Japan, and China are reviewed. Three known species are recognized: Cucujus coccinatus Lewis (1881), C. haematodes Erichson (1845), and C. mniszechi Grouvelle (1874). Cucujus imperialis Lewis (1879) is a junior synonym of C. mniszechi Grouvelle. Cucujus opacus Lewis (1888) is regarded as a subspecies of C. haematodes Erichson. Cucujus chinensis Lee and Sato, sp. nov. from China and. C. nigripennis Lee and Sato, sp. nov. from Taiwan are described. The larvae of Cucujus mniszechi Grouvelle are described for the first time.http://zoolstud.sinica.edu.tw/Journals/46.3/311.pdf