Cryptorhopalum triste LeConte

Kiselyova, Tatiana, 2002, Description Of The Larval And Pupal Stages Of Cryptorhopalum Triste Leconte (Coleoptera: Dermestidae), With Notes On Biology And Rearing, The Coleopterists Bulletin 56 (1), pp. 41-49 : 42-48

Cryptorhopalum triste LeConte

Descriptions

Mature larva ( Fig. 1 ). Length 3.8–4.6 mm. Integument of head, nota, and terga fuscous, sterna hyaline, coxae with diffuse fuscous pigmentation anteriorly, femora and tibiae yellowish. Setae golden­brown, some spicisetae on the terga dark brown. Hastisetae with shape of head as illustrated ( Figs. 2, 3 ); shaft of longest hastiseta about 1.8 times as long as pronotum. Longest terminal spiciseta about 8.2 times as long as pronotum. Frons without median tubercle. Antennal segment 2 ventrally with a filiform sensillum sunken in a cuticular cup ( Fig. 4 ). Labro­epipharyngeal margin with 6 setae in the outer series. Epipharynx with 9–12 sensory cups in the proximal transverse series, epipharyngeal rods as illustrated ( Fig. 6 ). Mandible with a short, asperate prostheca; mesal surface at the apex excavated and delimited by the rounded cutting edges dorsally and ventrally ( Fig. 5 ). Apex of galea with strong recurved setae ventrally and slender setae dorsally ( Figs. 7, 8 ). Ligula bilobed, with strong setae apically; hypopharynx with a deep median furrow and numerous scale­like asperities ( Fig. 9 ). Hypopharyngeal sclerome hyaline. Setal patterns of abdominal tergum 1 as illustrated ( Fig. 10 ); no spicisetae inserted on the posterior margins of nota and abdominal terga 1–6. Antecostal suture present on tergum 7, variable on tergum 8. Tergum 9 with a small circular depression medially ( Fig. 11 ). Ratio of length of mesosternal femur to width of pronotum 1:3.1. Ratio of length of tibia to length of femur 1:1.1. Anterior pretarsal seta on each leg 0.3 as long as pretarsus; posterior pretarsal seta 4/5 as long as anterior pretarsal seta.

Pupa ( Fig. 12): Length 3.5–3.9 mm. Integument creamy­white, with long, erect, honey­colored spicisetae distributed in patches on the head and dorsum, uniformly on wing pads. Gin traps and urogomphi absent. Pupa remains within the last larval exuvium ( Fig. 13 ), in which it is anchored by 2 clusters of long fine setae inserted on each side of the abdominal tergum 8. The setae from

THE COLEOPTERISTS BULLETIN 56(1), 2002 43

44 THE COLEOPTERISTS BULLETIN 56(1), 2002

THE COLEOPTERISTS BULLETIN 56(1), 2002 45

46 THE COLEOPTERISTS BULLETIN 56(1), 2002

THE COLEOPTERISTS BULLETIN 56(1), 2002 47

opposite sides cross over and adhere to the inner surface of segment 9 of the larval exuvium, on each side of the rectum.

Biology

Adults were observed in April and May in disturbed habitats, such as roadsides and forest clearings. In spring, V. radiata , H. radicata , and Senecio sp.

48 THE COLEOPTERISTS BULLETIN 56(1), 2002

common on Queen Anne’s lace, Anthriscus sylvestris (L.) ( Apiaceae ). On October 3, 1999, a single adult specimen was collected by J. Overmyer in Ben Burton Park, Athens, GA, where he observed numerous adults on Goldenrod, Solidago sp. , ( Asteraceae ) (pers. comm.).

Efforts were made to find the larvae at the sites of spring collection later in the season. Possible habitats, such as under loose bark of standing trees and near spider webs, were searched extensively, but with no success. However, cast skins of early instar larvae identified as Cryptorhopalum sp. were found on November 25, 1998, in Whitehall Forest, Clarke Co., GA, under loose bark of a standing oak charred by a forest fire. It is probable that larvae of C. triste are to be found in a similar habitat.

Figures

Fig. 1. Mature larva, dorsal habitus.

Figs. 2–8. 2) Head of hastiseta from abdominal tergum 1; 3) same, from membrane behind abdominal tergum 7; 4) antenna, ventral view; 5) mandible, left, dorsal view; 6) epipharynx; 7) maxilla, left, dorsal view; 8) right, ventral view. Scale line 0.1 mm.

Figs. 9–11. 9) Hypopharynx, fronto­lateral view; 10) abdominal tergum 1, left side, partially denuded; 11) abdominal tergum 9, denuded. Scale line 0.1 mm.

Fig. 13. Pupa within the last larval exuvium, dorsal view.