Fopius arisanus (Sonan, 1932)

See additional comments under the Fopius persulcatus species group on the Fopius page. An overview of the biology of this species has been published by Rousse et al. (2005)
Taxonomic History / Nomenclature
Opius oophilus Fullaway is a junior synonym (Wharton and Gilstrap 1983), and all of the biological control literature prior to about 1985 used the name oophilus.
Prior to the description of Fopius, the species now placed in this genus were most frequently included either in Opius or Biosteres. This particular species has also been placed, occasionally, in Diachasma. Thus, the names Opius oophilus, Biosteres oophilus, and Diachasma oophilus all refer to Fopius arisanus.
Members of the persulcatus species group (to which Fopius arisanus belongs) are characterized by the presence of striate sculpture on the second metasomal tergum (as in Fig. 8) and a frons that is densely covered with large punctures, giving the frons a somewhat rugose appearance (Figs. 3 and 4). This species is further characterized by generally dark abdomen and thoracic pleura and the absence of a ridge apically on the dorsal valve of the ovipositor.
1.Fopius arisanus habitus: lateral
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4. Fopius arisanus frons, ocelli, ...
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6. Fopius arisanus thorax: ...
7. Fopius arisanus abdomen: d...
8. Fopius arisanus abdom...
9. Fopius arisanus fore wing...
10.Fopius arisanus hind wing
Diagnosis and Relationships
Relationships among members of the genus Fopius have been briefly discussed by Wharton (1999).
Native to the Indo-Pacific Region, from at least India to Taiwan. This species was originally described from Taiwan.

Fullaway described Opius oophilus on the basis of specimens collected in Hawaii following the introduction of this species against Oriental fruit fly in the late 1940s, but oophilus was later recognized as a synonym of arisanus, originally described from Taiwan. The actual country of origin for the material introduced to Hawaii is uncertain (though believed to be Malaysia). Fopius arisanus has subsequently become established in several other countries, including Australia, Costa Rica, Fiji, and Mauritius (Wharton et al. 1981, Wharton and Gilstrap 1983) as a result of purposeful redistribution from Hawaii targeting a variety of pest tephritids (Wharton 1989). For a more recent summary, see Rousse et al. (2005).

Indonesia (Turica, A. 1968.)
Hawaii (Bess, H. A. 1953.; Carter, W. 1952.; Steiner, L. F. and Lee, R. K. S. 1955.; Tamashiro, M. and Sherman, M. 1955.; van den Bosch, R. and Haramoto, F. H. 1951.; van den Bosch, R.; Bess, H. A.; Haramoto, F. H. 1951.; Fischer, M. 1963.; Purcell, M. F. 1998.; Waterhouse, D. F. 1993.; Buckingham, G. R. 1968.; Haramoto, F. H. 1953.; Kaya, H. K. and Nishida, T. 1968.; Papp, J. 1985.; Ramadan, M. M.; Wong, T. T. Y.; McInnis, D. O. 1994.; Harris, E. J. and Bautista, R. C. 1994.; Palacio, I. P.; Ibrahim, A. G.; Ibrahim, R. 1991.; Ramadan, M. M.; Wong, T. T. Y.; Herr, J. C. 1994.; Vargas, R. I.; Stark, J. D.; Uchida, G. K.; Purcell, M. 1993.; Anonymous. 1953.; Gilstrap, F. E. and Hart, W. G. 1987.; Bess, H. A.; van den Bosch, R.; Haramoto, F. H. 1961.; Wharton, R. A. 1987.; Purcell, M. F.; Herr, J. C.; Messing, R. H.; Wong, T. T. Y. 1998.; Vargas, R. I.; Walsh, W. A.; Nishida, T. 1995.; Wong, T. T. Y.; Mochizuki, N.; Nishimoto, J. I. 1984.; Ramadan, M. M.; Wong, T. T. Y.; Beardsley, J. W. 1992.; Ramadan, M. M.; Wong, T. T. Y.; Messing, R. H. 1995.; Wong, T. T. Y. and Ramadan, M. M. 1987.; Wong, T. T. Y.; Ramadan, M. M.; McInnis, D. O.; Mochizuki, N.; Nishimoto, J. I.; Herr, J. C. 1991.; Wong, T. T. Y.; Ramadan, M. M.; Herr, J. C.; McInnis, D. O. 1992.; Bennett, F. D.; Rosen, D.; Cochereau, P.; Wood, B. J. 1976.; Haramoto, F. H. and Bess, H. A. 1970.; Nishida, T. and Napompeth, B. 1974.; Wilson, F. 1960.; Stark, J. D.; Vargas, R. I.; Thalman, R. K. 1991.; Bautista, R. C.; Harris, E. J.; Lawrence, P. O. 1998.; Chaudhry, M. M. K. 1989.; Purcell, M. F.; Jackson, C. G.; Long, J. P.; Batchelor, M. A. 1994.; Stark, J. D.; Vargas, R. I.; Walsh, W. A. 1994.; Vargas, R. I.; Walsh, W. A.; Hsu, C. L.; Spencer, J.; Mackey, B.; Whitehand, L. 1994.; Liquido, N. J. 1991.; Purcell, M. F.; Daniels, K. M.; Whitehand, L. C.; Messing, R. H. 1994.; Harris, E. J.; Okamoto, R. Y.; Lee, C. Y. L.; Nishida, T. 1991.; van den Bosch, R. 1952.; Bautista, R. C.; Mochizuki, N.; Spencer, J. P.; Harris, E. J., Ichimura, D. M. 1999.; Bess, H. A.; Haramota, F. H.; Hinckley, A. D. 1963.; Huffaker, C. B.; F. J. Simmonds; and Laing, J. E. 1976.; Laing, J. E. and Hamai, J. 1976.; Clausen, C. P. 1978.; Eitam, A. 1998.; Bautista, R. C.; Harris, E. J.; Vargas, R. I. 2001.; Harris, E. J. and Bautista, R. C. 2001.; Wang, S. G. and Messing R. H. 2002.; Vargas, R. I.; Peck, S. L.; McQuate, G. T.; Jackson, C. G.; Stark, J. D.; Armstrong, J. W. 2001.; Duan, J. J.; Messing, R. H.; Dukas, R. 2000.; Duan, J. J.; Messing, R. H.; Purcell, M. F. 1998.; Lopez, M.; Sivinski, J.; Rendon, P.; Holler, T.; Bloem, K.; Copeland, R.; Trostle, M.; Aluja, M. 2003.; Quimio, G. M. and Walter, G. H. 2001.; Wang, X. and Messing, R. H. 2003.; Lawrence, P. O.; Harris, E. J.; Bautista, R. C. 2000.; Harris, E. J.; Bautista, R. C.; Spencer, J. P. 2000.; Purcell, M. F.; Duan, J. J.; Messing, R. H. 1997.; Narayanan, E. S. and Batra, H. N. 1960.; Fry, J. M. 1989.; van den Bosch, R. 1951.; Clausen, C. P. 1953.; Anonymous (Joint legislative committe on agriculture and livestock problems). 1953.; Debach, P. and Rosen, D. 1991.; Wang, X. G. and Messing, R. H. 2004.; Wang, X. G. and Messing, R. H. 2004.; Wang, X. G.; Messing, R. H.; Bautista, R. C. 2003.; Wang, X. G.; Bokonon-Ganta, A. H.; Ramadan, M. M.; Messing R. H. 2004.; Ramadan, M. M. 2004.; Bautista, R. C.; Harris, E. J.; Vargas, R. I.; Jang, E. B. 2004.; Vargas, R. I.; Long, J.; Miller, N. W.; Delate, K.; Jackson, C. G.; Uchida, G. K.; Bautista, R. C.; Harris, E. J. 2004.; Jackson, C. G.; Vargas; R. I.; Suda, D. Y. 2003.; Duan, J. J. and Messing, R. H. 2000.)
Biology and Behavior
This species oviposits in the egg of the host. It is an egg-prepupal parasitoid, eventually emerging from the host puparium shortly after the latter is formed (killing the host before pupation takes place). Initial work on the biology of this species was published by van den Bosch et al. (1951), van den Bosch and Haramoto (1951), van den Bosch and Haramoto (1953), Hagen (1953), and Haramoto (1957). More recent studies include those of Snowball et al. (1962), Kaya and Nishida (1968), Wong et al. (1984), Williams et al. (1988), Ibrahim et al. (1992), Ramadan et al. (1992), Bautista and Harris (1996), Bautista et al. (1999) (mass rearing), Quimio and Walter (2000), Quimio and Walter (2001), Harris and Bautista (2001), Bautista et al. (2001), Vargas et al. (2002), Baeza-Larios et al. (2002), Falco et al. (2003), Wang and Messing (2003), and Altuzar et al. (2004). Wang and Messing (2003) explored the effects of several factors (indirect host stimuli, food supply, and mating status) on egg maturation in female F. arisanus, and found that only oviposition experience was directly associated with an increase in egg maturation. The authors suggest that providing laboratory-reared F. arisanus females with a constant supply of host eggs may increase parasitoid offspring in mass rearing, and maximize field parasitism of hosts after release. Additional experiments indicated that intraspecific competition occurs in superparasitized medfly eggs, resulting in high mortality of supernumerary F. arisanus eggs and first instar larvae by physiological suppression (Wang and Messing 2003).

Fopius arisanus has achieved a competitive advantage over other introduced parasitoid species in Hawaii. Wang and Messing (2003) have shown several mechanisms by which F. arisanus optimizes its parasitization capabilities including adjusting foraging time according to patch quality cues (presence of plant injury odors, kariomones, and previous experience in patch), utilizing a fixed set of host location behaviors (antennating, probing, detecting, and ovipositing), and discriminating nonparasitized from parasitized hosts for oviposition.

Similar to results from previous experiments with Diachasmimorpha tryoni (Wang and Messing 2003), Diachasmimorpha krausii, and Psyttalia concolor (Wang and Messing 2002), Wang et al. (2003) found that F. arisanus was the superior competitor when matched with Diachasmimorpha longicaudata. As an egg parasite, F. arisanus arrives on the host (Ceratitis capitata and Bactrocera dorsalis in these experiments) prior to D. longicaudata, a larval parasite, and suppresses development of D. longicaudata, primarily at the egg stage. The authors also report that in experiments with the 4 larval parasitoids none were able to directly destroy F. arisanus larvae during parasitism. Although a superior competitor among many fruit fly parasitoids, F. arisanus does not flourish in all environments including higher elevations and lower temperatures, and is not adapted to certain tephritid hosts including Bactrocera cucurbitae. These recent studies verify and expand on the earlier studies of interspecific competition by van den Bosch and Haramoto (1951), van den Bosch and Haramoto (1953) and Bess et al. (1961). For a detailed review of the biology of this species, see Rousse et al. (2005).

Biology - Host Range Testing
Based on its successful development on a range of tephritid pests against which it has been introduced, Fopius arisanus cannot be regarded as a strict specialist on Oriental fruit fly, Bactrocera dorsalis. However, there is clear evidence that not all fruit-infesting tephritids are suitable hosts. Under laboratory conditions, F. arisanus will oviposit in eggs of the melon fly Bactrocera cucurbitae (Nishida et al. 1953). Although it appears that F. arisanus is not able to develop in the melon fly egg, it has a negative effect on the fitness of the egg. Nishida and Haramoto (1953) tested the capability of F. arisanus to attack Bactrocera cucurbitae in Hawaii where Bactrocera dorsalis and B. cucurbitae have overlapping distributions. F. arisanus readily oviposited in B. cucurbitae causing up to 80% mortality of fly eggs, but failed to develop to the adult stage. Nishida and Haramoto also found B. cucurbitae to be immune to other parasitoids of B. dorsalis, including Fopius vandenboschi, Psyttalia incisi, and Diachasmimorpha longicaudatus. Bautista et al. (2004) provided similar information on arisanus and cucurbitae in Hawaii.

Other experimental studies provide evidence that F. arisanus is able to successfully parasitize and complete development in olive fly, Bactrocera oleae, as well as cause incidental fly egg mortality through ovipositor insertion (Calvitti et al. 2002). Similar results were obtained on Anastrepha suspensa after earlier failures (Lawrence et al. 2000) and on other species of Anastrepha (Zenil et al. 2004). Snowball and Lukins (1964) reared arisanus from several species of Bactrocera when it was introduced to Australia for biological control of Queensland fruit fly. Chinajariyawong et al. (2000) provide a long list of native hosts from Thailand and Malaysia.

The potential impact of F. arisanus and 2 other tephritid egg parasitoids (F. caudatus and F. ceratitivorus) on a nontarget flowerhead-feeding tephritid, Trupanea dubautiae, was evaluated by Wang et al. (2004). Trupanea dubautiae is critical for pollination of plants in Hawaii. In laboratory experiments, no evidence of parasitism of T. dubautiae by any of the 3 parasitoids was observed.

Biological Control
Successfully introduced to Hawaii during the biological control program against Oriental fruit fly, Bactrocera dorsalis (Clancy et al. 1952) and widely believed to be the most successful parasitoid introduced to Hawaii for biological control of tephritids (Bess et al. 1961, Clausen et al. 1965). Subsequent sampling programs in Hawaii confirm the dominance of arisanus and the importance of this species in suppressing both medfly and Oriental fruit fly (e.g. Wong et al. 1984, Wong and Ramadan 1987).

Efficacy in combination with SIT: Vargas et al. (1994) and Vargas (1996) and with bait sprays: Vargas et al. (2001).

Suggestions for augmentative biological control: Harris et al. (2000).

Potential for use against olive fly in California: Sime et al. (2008).

Introduced to Society Islands (Tahiti, Moorea, Raiatea, Tahaa, and Huahine) from Hawaii from 2002-2004, resulting in the most successful example of classical biological control of tephritid fruit flies in the Pacific area outside of Hawaii (Vargas et al. 2007).

A listing of F. arisanus introductions in the New World for biological control is provided below summarized from Ovruski, Aluja, Sivinski, and Wharton 2000:

Mexico—introduced in 1954 against Anastrepha ludens; Jimenez-Jimenez 1956.
Costa Rica—introduced in 1955 against Ceratitis capitata; specimens recovered, established (Holler et al. 1996, Wharton et al. 1981, Wharton et al. 1998).
Argentina—introduced in 1961 against C. capitata; Ovruski 1995.
Florida, USA—introduced 1974-75 against A. suspensa; Baranowski et al. 1993.

See also Rousse et al. 2005.