Cyclocephala pasadenae

Pest

Common name(s)

Pasadena masked chafer, southwestern masked chafer

Taxonomy

Family: Scarabaeidae Subfamily: Dynastinae Genus: Cyclocephala Species: Cyclocephala pasadenae (Casey, 1915)

Adult diagnosis

Total body length 12.0–14.0 mm (0.47–0.55 in). Body elongate oval. Elytra and pronotum tan to golden-brown in color; clypeus and frons black to dark brown. Head lacking horns or tubercles. Pronotum lacking horns or tubercles. Elytral lacking obvious striae. Lateral margin of front tibia with 3 teeth. Claws of front tibia noticeably more robust in males than females.

Larval diagnosis

(Ritcher, 1966): Grub C-shaped, not hump-backed, cylindrical, whitish. Maxilla with galea and lacinia fused or nearly so. Lacinia of maxilla with 3 well developed unci. Maxillary stridulatory teeth truncate. Inner, concave surface of mandible, distad of the molar area, smooth. Head yellow-brown to light reddish-brown, lacking coarse punctures. Dorsal surface of last antennal segment with 2–5 sensory spots. Legs 4-segmented. Spiracles of first 6 abdominal segments similar in size. Scutella of front and middle sections of thorax each with 2 setae. Anal opening transverse, straight or slightly curved. Plegmatia absent.

Native range

Southern U.S., northern Mexico. This species is known from the southern half of the U.S. (Hardy, 1991). It is most common in the southwestern states (Ratcliffe and Paulsen, 2008) and is also known from northern Mexico (Ratcliffe et al., 2013).

Plant host(s)

Larvae are associated with turf grasses (Jameson et al., 2009).

Life history

In Nebraska, this species has a single generation per year, with adults active from June to October. Adult abundance peaks strongly in July (Ratcliffe and Paulsen, 2008). Females lay eggs in the soil, with larvae feeding on both grass roots and organic soil debris. Adults do not appear to feed (Ritcher, 1966).

Pest potential

Moderate. The pest potential of this species is somewhat unclear. Some sources state that larvae rarely occur in sufficient density to cause serious turf damage (Ratcliffe and Paulsen, 2008). Other sources describe it as among the most destructive turf pests in its range (Jameson et al., 2009). In its small Hawaiian range, this species has been associated with visible turf damage, some caused indirectly when birds dig for grubs (Jameson et al., 2009).

Status in Hawaii

Established. Cyclocephala pasadenae is known only from a Waikaloa golf course on Big Island, where it was first recorded 2007 (Jameson et al., 2009). Anecdotal evidence from the golf course staff suggest it may have established as early as the mid 1990's (Jameson et al., 2009).

Status in Guam

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

Potential distribution and dispersal pathway

This species is attracted to lights at night (Ratcliffe and Paulsen, 2008) and could be attracted to well lit ports and airports. This would allow for hitchhiking on marine or air cargo. Because eggs are laid in turf grasses, it is possible that eggs or larvae could be transported in shipments of commercial sod. Cyclocephala pasadenae should be regarded as a potential invasive threat to the other U.S. Pacific territories and the Caribbean.

Similar species

Cyclocephala pasadenae is the only member of its genus known from Hawaii. It is superficially most similar to another turf pest, Anomala orientalis (oriental beetle). These species are easily separated by size (C. pasadenae at 12.0–14.0 mm [0.47–0.55 in] versus 7.0–11.0 mm [0.28–0.43 in] in A. orientalis) and examination of the front tarsi (C. pasadenae with 3 teeth along the lateral margin of the front tibia versus 2 teeth along the lateral margin in A. orientalis).

Other names (synonyms)

Cyclocephala mexica Martínez, Ochrosidia arizonica Casey, Ochrosidia facilis Casey, Ochrosidia melina Casey, Ochrosidia ovulata Casey, Ochrosidia pasadenae Casey, Ochrosidia pusilla Casey, Ochrosidia validiceps Casey

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Cyclocephala pasadenae male; photo by E.L. Engasser

Cyclocephala pasadenae male; photo by E.L. Engasser

Cyclocephala pasadenae male; photo by E.L. Engasser

Cyclocephala pasadenae male; photo by E.L. Engasser

Cyclocephala pasadenae male foretibia; photo by E.L. Engasser

Cyclocephala pasadenae male foretibia; photo by E.L. Engasser

Cyclocephala pasadenae female foretibia; photo by E.L. Engasser

Cyclocephala pasadenae female foretibia; photo by E.L. Engasser

Cyclocephala pasadenae male genitalia, caudal view; photo by E.L. Engasser

Cyclocephala pasadenae male genitalia, caudal view; photo by E.L. Engasser

Cyclocephala pasadenae male genitalia, lateral view; photo by E.L. Engasser

Cyclocephala pasadenae male genitalia, lateral view; photo by E.L. Engasser

distribution map for Cyclocephala pasadenae

distribution map for Cyclocephala pasadenae