Cotinis mutabilis

Potential Invader

Common name(s)

green June bug, green June beetle, figeater beetle

Taxonomy

Family: Scarabaeidae Subfamily: Cetoniinae Genus: Cotinis Species: Cotinis mutabilis (Gory and Percheron, 1833)

Adult diagnosis

Total body length 17.0–34.0 mm (0.67–1.34 in). Body shape vaguely pentagonal, somewhat dorsoventrally flattened. Color above velvety green, rarely black or plum; ventral color metallic green, rarely black or brownish; elytral margins or mid-disc often tan. Head with short process at apex of clypeus and short, anteriorly produced, horn-like process on frons. Scutellum hidden by pronotum. Sternum with strongly produced metasternal keel.

Larval diagnosis

(Ritcher, 1966): Live larvae crawl on their backs, legs up, and feel distinctly "squishy". Grub C-shaped, not hump-backed, cylindrical, whitish. Maxilla with galea and lacinia fused or nearly so. Labrum symmetrical, trilobed. Lacinia with fewer than 3 well-developed, terminal unci. Last antennal segment with sensory spots. Claws cylindrical; bearing 7 or more setae. Abdominal segments 9 and 10 fused. Anal opening transverse, straight or slightly curved. Raster with 2 or more irregular rows of pali; inner row of each palidium having 7–10 pali each much larger than those pali in the outer row.

Native range

Southwestern U.S. to northern South America. This species occurs from the southwestern U.S. (California, Nevada, Utah, Arizona, New Mexico, and Texas) south through Mexico and Central America into northern South America (Goodrich, 1966).

Plant host(s)

Adults have been reported on a number of plants, most of which are thin-skinned fruits: apple (Malus spp.), apricot (Prunus armeniaca), blackberry (Rubus spp.), grape (Vitis spp.), fig (Ficus carica), nectarine (Prunus persica), peach (Prunus persica), pear (Pyrus spp.), pineapple (Ananas comosus), plum (Prunus domestica), raspberry (Rubus spp.), and tomato (Solanum lycopersicum) (Davis, 2014). There are also reports of larvae damaging pineapple roots (Joy et al., 2013).

Life history

Adults of this species are diurnal, flying actively and noisily while searching for feeding or oviposition sites (Chapell, 1984). In Utah, adults are active in July and August (Davis, 2014), while in California adults are seen May through early October (Chapell, 1984). Eggs are laid in compost, manure, or organic rich soils, where larvae feed on organic debris and detritus (Davis, 2014).

Pest potential

Minor. Unlike the very similar looking Cotinis nitida, C. mutabilis is not a significant pest (Davis, 2014). Adults do not damage developing fruit, but they may actively seek out ripe fruit (Chapell, 1984) and can cause minor damage, particularly to thin-skinned fruits (Davis, 2014). There are few reports of larvae damaging roots (Camino-Lavín et al., 1996), although it is not clear that this is a common occurrence.

Status in Hawaii

Recorded, not established. In Hawaii, this species has been intercepted in quarantine at Hilo on Big Island. The specimen was collected in 2014 in an automobile that originated from San Diego, California. A 1964 record for Cotinis, also intercepted arriving from California, probably refers to this species (Look, 1974).

Status in Guam

Not established or recorded. There are no records of this species from Guam.

Potential distribution and dispersal pathway

This diurnal species is both widespread and a powerful flier (Chapell, 1984). It is possible that the frugivorous adults could be transported in commercial shipments of fruits, as may have occurred with the 2014 specimen.

Similar species

Though distinctive amongst recorded Hawaiian and Guamanian species, it is possible this beetle could be confused with Protaetia orientalis (Asian flower beetle) or Protaetia pryeri (Midway emerald beetle). A number of characters are useful in separating Cotinis and Protaetia, including: scutellum (Cotinis mutabilis with scutellum hidden under pronotum versus scutellum clearly visible in Protaetia spp.), color (Cotinis mutabilis usually velvety green versus dark brown or black with white maculations in Protaetia orientalis, shining bright green in Protaetia pryeri), head armature (Cotinis mutabilis with short, horn-like process on the frons and produced clypeal apex versus head armature absent in Protaetia spp.), and metasternal keel (Cotinis mutabilis with metasternal keel strongly produced, versus metasternal keel reduced in Protaetia spp.).

Other names (synonyms)

Cotinis abdominalis Casey, Cotinis arizonica Casey, Cotinis atrata (Gory and Percheron), Cotinis capito Casey, Cotinis malinus Janson, Cotinis mexicana (Gory and Percheron), Cotinis nigrorubra (Gory and Percheron), Cotinis obliqua Casey, Cotinis palliata (Gory and Percheron), Cotinis sobrina (Gory and Percheron), Cotinis texana Casey, Gymnetis mutabilis Gory and Percheron

Report your observation

In Hawaii, this species represents a new invasive species. Prevent the spread of this species by reporting your observation at our iNaturalist project.

Cotinis mutabilis; photo by E.L. Engasser

Cotinis mutabilis; photo by E.L. Engasser

Cotinis mutabilis; photo by E.L. Engasser

Cotinis mutabilis; photo by E.L. Engasser

Cotinis mutabilis color morph; photo by E.L. Engasser

Cotinis mutabilis color morph; photo by E.L. Engasser

Cotinis mutabilis color morph; photo by E.L. Engasser

Cotinis mutabilis color morph; photo by E.L. Engasser

Cotinis mutabilis male genitalia, dorsal view; photo by E.L. Engasser

Cotinis mutabilis male genitalia, dorsal view; photo by E.L. Engasser

Cotinis mutabilis male genitalia, lateral view; photo by E.L. Engasser

Cotinis mutabilis male genitalia, lateral view; photo by E.L. Engasser

distribution map for Cotinis mutabilis

distribution map for Cotinis mutabilis