Family: Scarabaeidae Subfamily: Melolonthinae Genus: Lepidiota Species: Lepidiota carolinensis Arrow, 1939
Total body length 19.0–21.9 mm (0.74–0.86 in). Body shape oblong, cylindrical, tapering slightly posteriorly. Color yellowish-brown; head, pronotum, and scutellum brownish-red. Antennae 10-segmented; club 3-segmented; club subequal in length to scape (male) or half the length of scape (female). Elytra with numerous small white scales; weakly striated.
Undescribed. For Lepidiota (Ahrens et al., 2007): Grub C-shaped, not hump-backed, cylindrical, whitish. Galea and lacinia fused proximally but separated distally or tightly fitted together. Frons rugose. Claws of hind legs reduced. Raster with 2 parallel rows of setae. Anal opening Y-shaped.
Poorly known. Cartwright and Gordon (1971) noted that this species comes to lights, suggesting nocturnal habits. It is likely that adults are folivores and that the larvae develop within soil where they feed on grass roots. Such habits are seen in related Lepidiota species (Kuniata and Young, 1992). There are likely one or two generations per year.
Probably none. There are no records of this poorly known species feeding on commercially important plants. However, a considerable number of related species are significant larval pests of grasses including (but not limited to) Lepidiota frenchi, L. squamulata, and L. stigma (all of which all feed on sugarcane) (Britton, 1962; Kuniata and Young, 1992), L. reuleauxi (a pest of sugarcane and corn) (Kuniata and Young, 1992), and L. vogeli (a pest of pasture grasses) (Barrett, 1966).
Not established or recorded. There are no records of this species from Hawaii.
Native. Cartwright and Gordon (1971) reported this species as endemic to Micronesia, occurring in the Marianas and Palau.
It appears unlikely that this rare, native species would spread beyond its small, natural range. However, because this scarab is attracted to lights at night (Cartwright and Gordon, 1971), it is possible this species could be attracted to well-lit ports and airports where it could be transported to new regions.
This scarab is somewhat similar to Holotrichia bipunctata, a common species on Guam. The species are separated by size (19.0–21.9 mm [0.74–0.86 in] in Lepidiota carolinensis versus 13.8–18.1 mm [0.54–0.71 in] in H. bipunctata) and elytra (L. carolinensis elytral surface with numerous, small, white scales versus scales lacking in H. bipunctata).
Report your observation of this rare and native Guamanian species at our iNaturalist project.