Synonyms and other taxonomic changes
Cactobrosis fernaldialis (Hulst, 1886)
Megaphycis fernaldialis Hulst, 1886
Euzophera gigantella Ragonot, 1901
Honora cinerella Hulst, 1901
Explanation of Names
Named in honor of entomologist Charles H.
Fernald (1838-1921).
Size
Powell & Opler (2009) reported the forewing length 14.5-20.5 mm., females much larger than males.
(1)Range
Powell & Opler (2009) reported the range to include Texas to southern California.
(1)Season
Powell & Opler (2009) reported late March to April and July to November.
(1)Food
Powell & Opler (2009) states that larvae feed in
fishhook barrel cactus (
Ferocactus wislizeni) and probably in other related cacti. Mann (1969), Betton (1972), Horst (2008) and the AZ Department of Agriculture also list the
saguaro cactus (
Carnegiea gigantea).
Life Cycle
Up to 100 larvae feed gregariously on one plant causing a yellowish appearance. They tunnel freely and eject frass through a few small holes. Pupation occurs in flimsy cocoons beneath the plant or nearby (Mann, 1969). Larvae feed at the base of saguaro buds and tunnel into the cactus (AZDA). Note: The Arizona-Sonora Desert Museum, under a
photo of the larva, states that the larvae are NOT gregarious.
Remarks
Larvae carry and transmit the bacteria (Erwinia carnegieana) that causes black necrosis disease and may play a major role in the decline of the saguaro cactus (Betton, 1972; Horst, 2008). The Arizona-Sonora Desert Museum website states that larvae rarely cause lethal damage to larger cacti. The cactus' reaction to the moth larva and bacteria results in a hard callus tissue growth that may be present in the carcass of a dead saguaro (pictured in Betton, 1972).
Print References
Betton, H.B. 1972. Physical and biological factors affecting the maintenance and management of the giant (Saguaro) cactus,
Cereus giganteus, Englem. BLM Evaluation. pp.
1-38
Horst, R.K. 2008. Westcott's plant disease handbook. 7th edition. Springer Reference.
p.106
Hulst, G.D. 1886. Descriptions of new Pyralidae.
Transactions of the American Entomological Society 13:
163.
Mann, J. 1969. Cactus-feeding insects and mites.
Bulletin of the United States National Museum 256. p.
70.
(2)
Neunzig, H.H., 1997.
The Moths of America North of Mexico, Fascicle 15.4. The Wedge Entomological Research Foundation. p. 47; plate 3, figs. 1-4.
(3)
Powell, J.A. & P.A. Opler 2009.
Moths of Western North America. University of California Press. plate 13, fig. 24; p. 196.
(1)Internet References
Arizona Department of Agriculture - AZDA on the bacterial necrosis of saguaro cacti
saguaro-juniper.com - photos of callus tissue growth caused by larvae
Saguaro Boots - more photos of callus tissue growth caused by larvae
