Fruit Fly Expert Identification System and Systematic Information

Norrbom Status of Knowledge 33
Drew & Hardy (1981), Grewal & Kapoor (1986[1809]), Mainx
(1976), Ponisch & Brandl (1992), Liang & Liang (1993),
Hunwattanakul & Baimai (1994), and Morgante et al. (1996)
described those of additional species. Most Tephritidae studied
to date have a diploid number of 12 (n=6), although several
species have eight, nine, ten or 14 chromosomes. Within the
family, there is considerable karyotypic variation in centromere
position, secondary constrictions, and chromosome size
(Solferini & Morgante 1987).
The sex determination system in Ceratitis capitata has
been reviewed by Lifschitz & Cladera (1989). Maleness is
determined by a small segment of the Y chromosome near the
centromere. In most other tephritids that have been studied, sex
determination systems have been described based on chromosome
morphology only (Berlocher 1993). Male heterogamety
is common in Trypetinae (13 spp. of Anastrepha, 5 spp. of
Bactrocera, Ceratitis capitata, 10 spp. of Rhagoletis, and 2 spp.
of Zonosemata) (Frias 1992[1597], Grewal & Kapoor
1986[1809]). Of these species, Anastrepha bistrigata, A. serpentina
and Rhagoletis striatella males have been reported as
X1X2Y, whereas R. meigenii may be X0. Two species of
Anastrepha and 14 species of Rhagoletis have been reported to
have isomorphic sex chromosomes, although most of the
Rhagoletis are probably male heterogametic except for R.
suavis, which is probably female heterogametic (Berlocher
1993).
Female heterogamety has been reported in some Tephritinae
(a total of 11 species of Cecidocharella, Oedaspis, Procecidochares,
Rachiptera, Acinia, Hyalopeza, Parahyalopeza, and
Tephritis), whereas Tephritis arnicae has been reported to have
a male XO sex determination system (Bush 1966[682], Frias
1992[1597]). Myopites inulaedyssentericae has heteromorphic
sex chromosomes, but in which sex this occurs has not been
determined (Ponisch & Brandl 1992). Six species of Urophora
and a total of six species of Dyseuaresta, Trupanea, and Trypanaresta
are reported to have isomorphic sex chromosomes
(Mainx 1976, Frias 1992[1597], Ponisch & Brandl 1992).
Biochemical and molecular studies
Various types of biochemical and molecular analyses involving
fruit flies have been conducted, but most were limited
to certain pest species for applied purposes. Most of these data
thus have limited systematic significance at this time. Some
studies have attempted to analyze phylogenetic relationships or
to discriminate taxa using biochemical characters.
Isozyme electrophoresis has been the biochemical technique
most commonly used on tephritids. Rhagoletis is the most
extensively investigated genus (Berlocher 1980, Berlocher &
Bush 1982, Berlocher et al. 1993, Payne & Berlocher
1995[3769]), and a key and phylogenies have been proposed
based on allozyme data. Gasperi et al. (1991) and Kourti et al.
(1992) analyzed the geographic isozyme variability of Ceratitis
capitata and its significance regarding the dispersion of this
species. At least some isozymes have been studied in 17 species
of Anastrepha, including A. fraterculus, which is probably a
complex of several cryptic species (Morgante et al. 1980, 1996,
Matioli et al. 1986, Steck 1991, Stefani & Morgante 1996), and
in 13 species of Bactrocera (McKechnie 1975, Drew & Hardy
1981, Yong 1988, 1990[5250], 1992[5254], 1993, 1995,
Zouros & Loukas 1989, Ooi 1991, Dadour et al. 1992, Drew &
Hancock 1994[1238], Ochando et al. 1994), nine species of
Blepharoneura (Condon & Steck, in press), Capparimyia
savastani and two species of Ceratitis (Gasperi et al. 1987,
Malacrida et al. 1991, Kourti et al. 1992), Chaetostomella
undosa (Steck 1981), four species of Euaresta (Berlocher
1984[410]), Eurosta solidaginis (Waring et al. 1990), six species
of Neaspilota (Steck 1981), Oxyna parietina (Eber et al.
1992), Paraterellia immaculata (Steck 1981), Tephritis bardanae
(Eber et al. 1991), four species of Terellia (Steck
1981, Muller-Scharer et al. 1991), Trirhithrum coffeae (Malacrida
et al. 1991), and Urophora cardui (Eber & Brandl 1994).
Simon (1969) used serological techniques to analyze
Rhagoletis pomonella host races and R. mendax, and Kitto
(1983) and Sarma et al. (1987) used immunological techniques
to compare alpha-glycerophosphate dehydrogenase in 16 species
in 12 genera of Tephritidae, but there have been no subsequent
studies of fruit flies using these methods.
DNA research is a rapidly developing area in the study of
Tephritidae as for many other insect groups. Han & McPheron
(1994, 1997) and McPheron & Han (1997) studied two DNA
segments; they partially sequenced the nuclear 18S ribosomal
gene of 26 species of fruit flies in 21 genera and the mitochondrial
16S ribosomal RNA gene in 50 species in 28 genera. Other
sequences of nuclear and/or mitochondrial DNA have been
studied in Anastrepha suspensa and fraterculus, seven species
of Bactrocera, Ceratitis capitata, two species of Eurosta, and
several species of Rhagoletis (Haymer et al. 1990, Anleitner &
Haymer 1992, Soto-Adames et al. 1994, He & Haymer 1994,
Steck & Sheppard 1993, Gasparich et al. 1995, McPheron et al.
1995, Frommer et al. 1996, White 1996, Brown et al. 1996,
Hoeben et al. 1996). Haymer et al. (1994) developed DNA
probes that can be used to distinguish Ceratitis capitata, Bactrocera
cucurbitae and B. dorsalis.
Cuticular hydrocarbons have been analyzed in eight species
of Anastrepha, two species of Ceratitis, and four species
of Bactrocera, and have proven useful to discriminate adults
and larvae of these taxa, except among some of the Anastrepha
species (Carlson & Yocum 1986, Goh et al. 1993, Sutton &
Carlson 1993, Sutton & Steck 1994).
Male sex pheromones have been identified, at least partially,
for two species of Anastrepha (Nation 1975, 1989), nine
species of Bactrocera (Koyama 1989[2772], Mazomenos
1989, Perkins et al. 1990), Ceratitis capitata (Jones
1989[2523], Heath et al. 1991), and Toxotrypana curvicauda
(Chuman et al. 1987), but there is evidence for their presence
in other species and genera. The diverse composition of the
pheromones of the few species studied thus far allows little
generalization. Evidence for host-marking pheromones has
been reported in ten Rhagoletis species, two Anastrepha, Capparimyia
savastani, Ceratitis capitata, Paraceratitella eurycephala,
and Tephritis bardanae, but the pheromones have
been identified only in Rhagoletis cerasi (Averill & Prokopy
1989[247], Straw 1989[4692], Freidberg 1990).
Response to certain chemical attractants, such as cue lure,
methyl eugenol, or trimedlure, has been considered taxonomically
useful in the Dacina and Ceratitidina (Hancock 1987,
Drew 1989[232]).