DERMESTIDAE (CARPET BEETLES)

Grimaldi, David A., Sunderlin, David, Aaroe, Georgene A., Dempsky, Michelle R., Parker, Nancy E., Tillery, George Q., White, Jaclyn G., Barden, Phillip, Nascimbene, Paul C. & Williams, Christopher J., 2018, Biological Inclusions in Amber from the Paleogene Chickaloon Formation of Alaska, American Museum Novitates 2018 (3908), pp. 1-37 : 25

DERMESTIDAE (CARPET BEETLES)

Figures 8 A−C; 14F

AMNH LC-II-B4: A partial larva that is missing the head and legs, but has seven abdominal segments largely to entirely preserved (portions of the anterior segments are lost at the amber surface on the right side) (fig. 8A). The dorsum of the abdomen is covered with a dense vestiture of long setae having short, thick plumosity; presence/absence of bare patches on tergites is not observable. The apical abdominal segments have tuπs of peculiar spear-shaped setae, which are very well preserved. These specialized setae have a bullet-shaped head that is hollow, with an asymmetrical, sharp basal rim; the setal shaπ has evenly spaced nodes, each node with a crenulated collar of small spines or tubercles (fig. 14F). Such setae, called hastisetae, allowed identification of the partial larva to the Dermestidae , and in fact hastisetae of this structure are confined to the subfamily Megatominae ( Kiselyova and McHugh, 2006) , most similar to the genus Cryptorhopalum . The hastisetae in extant dermestids are defensive, being dehiscent and snagging together when the larva is attacked, entangling the attacker ( Nutting and Spangler, 1969). There are 1300 living species of Dermestidae in 53 genera, well-known for their larval diet of dried animal remains (including carrion, and shed feathers, hairs, and skin in nests). The genus Anthrenus (also a megatomine) is the notorious museum pest that decimates unprotected collections of skins and pinned insects. The oldest putative dermestid is in Jurassic shale ( Deng et al., 2017), with definitive larvae and adults in Early Cretaceous amber from Lebanon ( Kirejtshuk et al., 2009), and the oldest Attageninae from the mid-Cretaceous of Myanmar ( Cai et al., 2017) and Late Cretaceous of New Jersey ( Peris and Háva, 2016). Hastisetae of megatomine dermestids are preserved in Upper Albian–aged amber from Spain, snagged in the legs and body of ticks ( Peñalver et al., 2017). The ticks most likely acquired the hastisetae in the arboreal nest of a vertebrate host ( Peñalver et al., 2017). Diverse modern genera of dermestids occur in Eocene Baltic amber (e.g., Háva et al., 2008) and Miocene Dominican amber. The Chickaloon amber specimen is the most northerly fossil record of the Dermestidae , the prior ones being in Baltic amber.

Figures

FIG. 8. Abdomen of a larval beetle (Coleoptera), family Dermestidae subfamily Megatominae (AMNH LC- II-B4). A. Entire specimen. B. Detail of plumose setae. C. Detail of posterior tuπs of specialized, entangling hastisetae.