A revision of the neotropical genus ischioscia verhoeff,with descriptions of four new species (isopoda,philosciidae)

A revision of the species of the Proischioscia‐Ischioscia‐group revealed the necessity to synony‐mize the genus Proischioscia Vandel, 1968 with Ischioscia Verhoeff, 1928. The following previously described species are accepted and included in the genus Ischioscia: Ischioscia lobifera Verhoeff, 1928,Ischioscia amazónica Lemos de Castro, 1955, Proischioscia andina Vandel, 1968, Ischioscia bolivari Vandel, 1968, and Proischioscia sturmi Vandel, 1972. Four new species are described: I. stenocarpa, I. hanagarthi and I. longicauda from Peru, and I. irmleri from Brazil. An analysis of the generic and specific characters is given from a viewpoint of phylogenetic systematics.     

The phylogeny of the genus Ischioscia Verhoeff, 1928, with redescriptions of three species (Crustacea: Isopoda: Oniscidea)

The genus Ischioscia Verhoeff, 1928 is reviewed. 26 species are considered valid. A key for their identification is given, as well as a map showing the geographic distribution. The known range of the genus covers a large area from the central Amazon region to the mountains of Guatemala. The species of Ischioscia have a typical “philosciid” habitus (“runner” type); they can be distinguished from other Neotropical species with similar habitus by the following apomorphies: (1) male pereiopod 1 carpus enlarged to a plate-like extension, (2) scale field on male pereiopod 1 covering entire frontal side of the carpus, (3) male pereiopod 7 ischium with a ventral scale field, (4) dactylus in both sexes with a long inner claw. The groundpattern of Ischioscia is reconstructed, and an analysis of the phylogenetic relations within the genus is made on the basis of morphological data. The species are very similar to each other, most differences are found in the male structures of sexually dimorphic features. Ischioscia sturmi (Vandel, 1972), I. amazonica Lemos de Castro, 1955 and I. bolivari Vandel, 1968 are redescribed in detail.     

Analysis of mitochondrial COI sequences of the Diachasmimorpha longicaudata (Hymenoptera: Braconidae) species complex in Thailand

Diachasmimorpha longicaudata is an Opiinae parasitoid used to control tephritid fruit flies, which cause tremendous economic losses of fruits worldwide. In Thailand, D. longicaudata is classified as three sibling species, DLA, DLB and DLBB, based on the morphological and biological species concepts but their genetic variation has not been studied. Therefore, we investigated the genetic differentiation of the mitochondrial COI gene to clarify the ambiguous taxonomy of this species complex. The 603‐bp COI region was sequenced from laboratory‐bred colonies and field‐collected specimens from seven locations representing five geographical regions in Thailand. DLA was associated with the host Bactrocera correcta while DLB and DLBB were associated with Bactrocera dorsalis. The interspecific nucleotide differences of COI sequences among the three groups ranged from 6.70% to 7.62% (Kimura 2‐parameter distance), which adequately separates species complexes within the order Hymenoptera and supports the current sibling species classification. The neighbor joining, maximum likelihood and consensus Bayesian phylogenetic trees constructed from COI sequences revealed that the three sibling species of laboratory and field‐collected D. longicaudata are monophyletic with 100% support. The high genetic variation and molecular phylogeny of the COI sequences were shown to discriminate between the D. longicaudata species examined in this study.     

Response of two parasitoid species (Hymenoptera: Braconidae,Figitidae) to tephritid host and host food substrate cues

The Neotropical‐native figitid Aganaspis pelleranoi (Brèthes) and the Asian braconid Diachasmimorpha longicaudata (Ashmead) are two parasitoids of Tephritidae fruit flies with long and recent, respectively, evolutionary histories in the Neotropics. Both species experienced a recent range of overlap. In Argentina, A. pelleranoi is a potential species in biological control programs against the pestiferous tephritid species, Anastrepha fraterculus (Wiedemann) and Ceratitis capitata (Wiedemann), whereas D. longicaudata is already used in open‐field releases against Medfly in central‐western Argentina. To characterize the host‐foraging strategies of A. pelleranoi and D. longicaudata, olfactometer experiments were conducted comparing responses to C. capitata and A. fraterculus larvae, in two kinds of food substrate: fruit and artificial larval medium. To control the possible influence of host larvae used for parasitoid rearing on olfactory response, two strains of both parasitoid species, reared on both tephrtid species, were studied. Volatiles directly emanating either from A. fraterculus or C. capitata larvae may be detected by both A. pelleranoi and D. longicaudata, although chemical stimuli originating from the combination of host larvae and the habitat of the host were preferred. However, olfactory cues associated with host larvae probably play a relevant role in host searching behaviour of A. pelleranoi, whereas for D. longicaudata, the host‐habitat olfactory stimuli would be highly essential in short‐range host location. The strain of the parasitoids did not affect host search ability on the two tephritid species evaluated. These evidences are relevant for mass production of both parasitoids and their impact following open‐field augmentative releases.     

Intrinsic competition between Diachasmimorpha longicaudata and three native species of parasitoids (Hymenoptera: Braconidae: Opiinae) of Anastrepha (Diptera: Tephritidae) fruit flies under laboratory conditions

The effect of intrinsic competition between the exotic parasitoid Diachasmimorpha longicaudata (Ashmead) and the native species Doryctobracon crawfordi (Viereck), Utetes anastrephae (Viereck) and Opius hirtus (Fischer) (all Braconidae: Opiinae) was studied under laboratory conditions. Each native species and D. longicaudata acted as both a resident and an invader, and all species were introduced to the host simultaneously. Diachasmimorpha longicaudata was found to be the most competitive species because it achieved the highest parasitism percentage under all the experimental conditions, but it was also negatively affected by the presence and parasitic activity of the native parasitoids. Utetes anastrephae was the only species that maintained its parasitic rate when all species attacked the available hosts simultaneously. The emergence probability of a female D. longicaudata was positively associated with the increase in the number of scars on the cuticle of the host pupa, but this association was not observed for the native species. It was concluded that D. longicaudata is an intrinsic competitor that is superior to D. crawfordi, U. anastrephae and O. hirtus, whether acting as a resident or an invader, producing a female-biased sex ratio in all the evaluation conditions. Utetes anastrephae was the native species that was least affected by the competitive presence of D. longicaudata, which suggests that it could be used as a complementary biological control agent for Anastrepha fruit flies.     

The bumblebees of the subgenus Subterraneobombus: integrating evidence from morphology and DNA barcodes (Hymenoptera,Apidae, Bombus)

Although bumblebees have received a lot of attention, some taxonomic problems have persisted for many years. One particularly obdurate case has been the species of the subgenus Subterraneobombus. We revise the bees of this subgenus by integrating evidence from both morphology and, for a 5% subsample, from DNA (cytochrome c oxidase subunit 1, CO1) barcodes from pinned museum specimens. We apply a reciprocal illumination procedure: (1) taxa recognized previously from morphology are used to stratify samples for DNA subsampling; (2) DNA barcodes from these subsamples are used to recognize groups of phylogenetically related specimens; and (3) for these groups, we re‐examine morphological characters in order to recognize and diagnose species. A total of 3854 specimens from 1535 samples from across the geographic range of the subgenus throughout the Holarctic and northern Oriental regions are identified to 11 species. This includes one species newly recognized from Mongolia, Bombus mongolensis Williams sp. nov. Taxon concepts are modified substantially for four species, seven lectotypes are designated, and four new synonyms are recognized. The prevailing usage of Bombus distinguendus is maintained as valid by designating Bombus elegans as a nomen oblitum and designating B. distinguendus as a nomen protectum. Identification keys and colour‐pattern diagrams are provided, and geographic distributions, elevational ranges, and phenological activity periods are described to characterize the species. An estimate of the biogeographic history is reconstructed with dispersal–vicariance analysis. In this study, DNA barcode data have been a cost‐effective source of additional characters for diagnosing groups of specimens. The barcode data contributed directly to recognizing the one new species, of which females remain difficult to identify from morphology alone. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 813–862.     

The phylogeny of the genus Ischioscia Verhoeff, 1928, with redescriptions of three species (Crustacea: Isopoda: Oniscidea)

The genus Ischioscia Verhoeff, 1928 is reviewed. 26 species are considered valid. A key for their identification is given, as well as a map showing the geographic distribution. The known range of the genus covers a large area from the central Amazon region to the mountains of Guatemala. The species of Ischioscia have a typical “philosciid” habitus (“runner” type); they can be distinguished from other Neotropical species with similar habitus by the following apomorphies: (1) male pereiopod 1 carpus enlarged to a plate-like extension, (2) scale field on male pereiopod 1 covering entire frontal side of the carpus, (3) male pereiopod 7 ischium with a ventral scale field, (4) dactylus in both sexes with a long inner claw. The groundpattern of Ischioscia is reconstructed, and an analysis of the phylogenetic relations within the genus is made on the basis of morphological data. The species are very similar to each other, most differences are found in the male structures of sexually dimorphic features. Ischioscia sturmi (Vandel, 1972), I. amazonica Lemos de Castro, 1955 and I. bolivari Vandel, 1968 are redescribed in detail.     

Effect of host diet and adult parasitoid diet on egg load dynamics and egg size of braconid parasitoids attacking Anastrepha ludens

The quantity and quality of host nutrients can affect fitness‐related traits in hymenopteran parasitoids, including oogenesis. The present study tested the prediction that a high host quality will influence oogenesis‐related traits positively in synovigenic parasitoids, and that a high‐quality adult parasitoid diet can positively affect the same parameters, potentially compensating for development on low‐quality hosts. Four braconid parasitoid species with contrasting life histories are reared on a low‐quality diet [Anastrepha ludens Loew (Diptera: Tephritidae) larvae reared on mango] or a high‐quality (artificial) diet. Adult parasitoids are provided with a high‐quality (honey ad libitum), moderate‐quality (honey every other day) or low‐quality (guava pulp) diet. Generalist species that encounter high variation in host quality naturally are predicted to be more flexible in dealing with nutrient shortfalls than specialist species. By contrast to the predictions, low‐quality hosts yield parasitoids with higher egg loads in two species: Opius hirtus Fisher and Diachasmimorpha longicaudata Ashmead. However, as predicted, a high‐quality adult diet exerts a positive effect on egg load (Utetes anastrephae Viereck), egg size (Doryctobracon crawfordi Viereck) and egg maturation rate (D. longicaudata, O. hirtus and U. anastrephae). The generalist D. longicaudata varies in egg load and maturation rate depending on host quality and adult diet, respectively. Evidence of the combined effect of both factors on parasitoid fertility is presented for the specialist O. hirtus. The theoretical and practical implications of these findings are discussed.     

Effect of Two Opiine Parasitoids (Hymenoptera: Braconidae) Introduced for Fruit Fly Control on a Native Hawaiian Tephritid,Trupanea dubautiae(Diptera: Tephritidae)

Diachasmimorpha longicaudata(Ashmead) andPsyttalia fletcheri(Silvestri) are opiine parasitoids introduced into Hawaii for control of the Oriental fruit fly,Bactrocera dorsalis(Hendel) and the melon fly,Bactrocera cucurbitae(Coquillett), respectively. Both species have recently been mass-reared and released for research in augmentative biocontrol programs. Laboratory and field sleeve cage experiments were conducted to investigate the potential impact of mass-producedD. longicaudataandP. fletcherion a native Hawaiian tephritid,Trupanea dubautiae(Bryan), infesting the flowerheads of the native composite shrubDubautia raillardioidesHillebrand. Gravid females ofD. longicaudataandP. fletcheriwere confined with bloomingD. raillardioidesflowerheads infested with late instarT. dubautiae.BothD. longicaudataandP. fletcherilacked positive oviposition responses toT. dubautiaelarvae in infested flowerheads and caused neither parasitism nor mortality to the flies. However, when larvae were removed from the flowerheads and presented in screened dishes containing artificial diet of the parasitoids' normal rearing hosts (B. dorsalisandB. cucurbitae), bothD. longicaudataandP. fletcherireadily oviposited in the test larvae. Oviposition byD. longicaudatadid not significantly affect the percentage pupation ofT. dubautiae,but did reduce the emergence of adult flies. Oviposition byP. fletcherisignificantly reduced both pupation and adult fly emergence. All progeny of both parasitoid species died as eggs or first-instar larvae. Results from our experiments demonstrate that biological control programs targeted against frugivorous tephritid pests byD. longicaudataandP. fletcherihave no harmful impact on flowerhead-infestingT. dubautiae.     

Geometric morphometrics for the taxonomy of 11 species of Anopheles (Nyssorhynchus) mosquitoes

The subgenus Anopheles (Nyssorhynchus) (Diptera: Culicidae) includes the primary vectors of Plasmodium spp. in Colombia. Most adult females of this subgenus are difficult to identify in the field using the available keys. With the objective of further investigating the discriminatory power of modern morphometrics, both landmark‐based and outline‐based approaches were explored using the wing venation geometry of 11 Anopheles (Nyssorhynchus) species. Wing shape was able to separate the closest species of the subgenus. When the 11 species were analysed together, validated classification scores on average 5.3–8.6 times higher than those expected by chance were observed. These scores computed from the total sample of 11 species were not satisfactory for the recognition of Anopheles benarrochi B, Anopheles oswaldoi s.l. and Anopheles strodei. These sibling species were captured in sympatry. To improve the identification power of the morphometric tool, it was necessary to analyse these species separately from the remaining species. The best classification scores were obtained using a combination of 12 landmarks collected not only on the intersections of wing veins, but also on spots. An outline approach also gave excellent reclassification scores. Another pair of sibling species, collected in allopatry, Anopheles nuneztovari and Anopheles rangeli, also showed high classification scores.     

First Chemical Analysis and Characterization of the Male Species‐Specific Cephalic Labial‐Gland Secretions of South American Bumblebees

The evolution of signals and reproductive traits involved in the pre‐mating recognition has been in focus of abundant research in several model species, such as bumblebees (genus Bombus). However, the most‐studied bumblebee reproductive trait, the male cephalic labial gland secretions (CLGS), remains unknown among bumblebee species from South America. In this study, the CLGS of five South American bumblebees of the subgenera Thoracobombus (Bombus excellens and B. atratus) and Cullumanobombus (B. rubicundus, B. hortulanus, and B. melaleucus) were investigated, by comparing the chemical compositions of their secretions to those of closely related European species. The results showed an obvious interspecific differentiation in both subgenera. The interspecific differentiation among the species of the Thoracobombus subgenus involved different compounds present at high contents (main compounds), while those of the Cullumanobombus subgenus shared the same main components. This suggests that among the species of the Cullumanobombus subgenus, the differentiation in minor components could lead to species discrimination.     

Reduced cephalic labial glands in the male bumblebees of the subgenus Rhodobombus Dalla Torre (Hymenoptera: Apidae: Bombus Latreille)

Until now, all males of bumblebees are known to attract conspecific females by marking places with a chemical signal secreted by their cephalic labial gland. The specific combination of patrolling flight and scentmarking is of outmost importance to bumblebees as it is their main species specific recognition system. We report here the lack of that recognition system in species of the subgenus Rhodobombus by comparing the morphology and histology of the cephalic labial glands of Bombus (Rhodobombus) mesomelas with those of a well known species, B. (Bombus) terrestris (L.) The cephalic labial glands are much smaller in B. mesomelas than in other bumblebees species and most likely non-functional. This morphology is also observed in B. pomorum and B. brodmanni which also belong to the subgenus Rhodobombus. Our morphological observations are consistent with the chemical analyses of the secretions in B. mesomelas and B. pomorum which are very limited and of most unusual composition for a bumblebee. In addition, whereas other species are thought to use their barbae mandibularis to spread their secretion onto the substrate, these structures are absent in all Rhodobombus. All these observations would mean that the males of Rhodobombus do not attract females from far away by the use of their cephalic labial gland secretions.     

Chloroplast DNA variation in diploid and polyploid species of Bromus (Poaceae) subgenera Festucaria and Ceratochloa

Summary Chloroplast DNA (cpDNA) restriction endonuclease patterns are used to examine phylogenetic relationships between Bromus subgenera Festucaria and Ceratochloa. Festucaria is considered monophyletic based on the L genome, while Ceratochloa encompasses two species complexes: the B. catharticus complex, which evolved by combining three different genomes, and the B. carinatus complex, which is thought to have originated from hybridization between polyploid species of B. catharticus and diploid members of Festucaria. All species of subgenus Ceratochloa (hexaploids and octoploids) were identical in chloroplast DNA sequences. Similarly, polyploid species of subgenus Festucaria, except for B. auleticus, were identical in cpDNA sequences. In contrast, diploid species of subgenus Festucaria showed various degrees of nucleotide sequence divergence. Species of subgenus Ceratochloa appeared monophyletic and phylogenetically closely related to the diploid B. anomalus and B. auleticus of subgenus Festucaria. The remaining diploid and polyploid species of subgenus Festucaria appeared in a distinct grouping. The study suggests that the B. catharticus complex must have been the maternal parent in the proposed hybrid origin of B. carinatus complex. Although there is no direct evidence for the paternal parent of the latter complex, the cpDNA study shows the complex to be phylogenetically very related to the diploid B. anomalus of subgenus Festucaria.     

ITS2 sequence variations among members of Diachasmimorpha longicaudata complex (Hymenoptera: Braconidae) in Thailand

The parasitoid Diachasmimorpha longicaudata complex in Thailand contains at least 3 cryptic species informally designated as species D. longicaudata A, B and BB. DNA sequence data of nuclear ITS2 (second internal transcribed spacer) were used to characterize members of this D. longicaudata complex. The polymerase chain reaction (PCR) amplicon of ITS2 region of D. longicaudata B (≈ 650 bp) clearly differentiated this species from A and BB (amplicon of ≈ 590 bp). Sequence alignment of individual parasitoids revealed that low intraspecies differences ranged from 0.457 to 3.991%, but interspecies differences ranged from 7.566 to 12.989%. Phylogenetic trees constructed using Neighbor-Joining (NJ) and Maximum Parsimony (MP) methods, taking the parasitoid Psyttalia concolor complex as an outgroup, revealed that D. longicaudata A, B and BB formed a monophyletic group, with species A and BB being more closely related than species B. ITS2 characterization of D. longicaudata complex has revealed an interesting divergence of the three cryptic sibling species in Thailand.     

A systematic study of the polyphenolic composition of aqueous extracts deriving from several Cistus genus species: evolutionary relationship

Introduction – Cistaceae is a large family of shrubs widely spread over the Mediterranean area. It includes Helianthemum, Halimium and Cistus genus. Cistus genus contains approximately 20 species distributed in three subgenus. The essential oil of Cistus species has been thoroughly studied, but the polyphenolic composition of the aerial parts of the different Cistus species needs further characterisation. Objective – To perform a comparative analysis of the qualitative and quantitative polyphenolic composition of the aerial parts of the most commonly distributed Spanish Cistus species in order to find a relationship between chemotype and subgenus. Methodology – Thirteen aqueous extracts derived from 10 different Cistus species were analysed by using HPLC with diode array‐detection coupled to electrospray ion trap mass spectrometry technique (HPLC‐DAD‐ESI‐MS/MS). Their major compounds were identified and ellagitannins were quantified. Principal component analysis (PCA) was performed on the most relevant compounds to find out the statistical association between chemotype and variety. Results – Three main groups of compounds were found, i.e. ellagitannins, flavonoids and phenolic acids derivatives. The polyphenolic profile was specific for each species, although the abundance of some compounds also varied depending on the soil type. Whereas C. ladanifer, C. salviifolius, C. populifolius and C. libanotis were specially rich in ellagitannins, C. clusii, C. laurifolius and C. monspeliensis contained significant amounts of flavonoids and much less ellagitannins. In contrast, C. crispus, C. incanus and C. albidus showed a polyphenolic profile mostly based on flavonoids. PCA analysis showed a strong relationship between Cistus subgenus and its chemotype based on the most relevant water‐soluble polyphenolic compounds. Conclusions – Chemical composition of the leaves' aqueous extracts from plants belonging to the Cistus genus is strongly related to their subgenus, in agreement to previous taxonomical and phylogenetic divisions. In contrast, soil and climate are less influencing factors. Leucocistus and Halimioides subgenus showed a higher content in ellagitannins. However, Cistus subgenus had higher flavonoid content. Copyright © 2011 John Wiley & Sons, Ltd.     

Microsympatry in cryptic lowland salamanders (Caudata: Plethodontidae: Bolitoglossa subgenus Nanotriton) from north‐western Honduras: implications for taxonomy and regional biogeography

The taxonomy of the diminutive bolitoglossine salamanders of the subgenus Nanotriton has previously been a source of confusion among specialists. At various times, at least three different species of Nanotriton have been reported to occur in Honduras: Bolitoglossa nympha, B. occidentalis and B. rufescens. Phylogenetic analysis of 16S and cyt b from samples from three localities in Honduras (departments of Yoro, Copán and Cortés) confirms that most populations are assignable to B. nympha. Nine samples collected from a single locality on the northern slope of the Sierra de Omoa, between 120 and 190 m in elevation, were found to represent two distinct taxa: B. nympha and B. rufescens. Field examination of these nine specimens found them to be morphologically indistinguishable, including a lack of maxillary teeth in all specimens. As such, in situ identification of the two species in north‐western Honduras is problematic given the occurrence of the two taxa in microsympatry in at least one locality. The discovery of yet another divergent lineage of B. rufescens highlights the need for a taxonomic reassessment within this species complex.     

Phylogenetics,historical biogeography and molecular species delimitation of Gnaptorina Reitter (Coleoptera: Tenebrionidae: Blaptini)

With 38 described species or subspecies, Gnaptorina Reitter is the second‐most species‐rich genus in the darkling beetle subtribe Gnaptorinina (Tenebrionidae: Tenebrioninae). In this study, we reconstructed a phylogeny of the genus based on one nuclear and three mitochondrial genes and used this phylogeny to explore the historical biography and diversification of Gnaptorina species. We implemented multiple molecular species delimitation approaches to reassess the status of Gnaptorina species and taxonomic subdivisions of the genus. Dating and historical biogeography analyses suggest an early Eocene origin of the genus, with the southeastern regions of the Tibetan Plateau most likely as areas of origin. Based on these results, we propose a new classification for Gnaptorina with three major clades identified. Consequently, the monotypic subgenus Boreoptorina is newly synonymized with the more species‐rich subgenus Hesperoptorina, and G. dongdashanensis Shi is transferred from Hesperoptorina to the subgenus Gnaptorina. In addition, G. minxiana Medvedev, formerly treated as a subspecies of G. potanini Reitter, is elevated to species. Results of molecular species delimitation analyses are largely congruent and confirm the status of most morphological species.     

Phylogenetic relationships and convergent evolution of ocean‐shore ground beetles (Coleoptera: Carabidae: Trechinae: Bembidion and relatives)

Through phylogenetic analysis of seven genes, we show that there have been at least six independent entries into intertidal habitats in the history of bembidiine carabids, in the ancestors of: (i) Orzolina Machado, (ii) Bembidion (Desarmatocillenus Netolitzky), (iii) Bembidion laticeps (LeConte) + palosverdes Kavanaugh & Erwin, (iv) Bembidion laterale (Samouelle), (v) Bembidion umi Sasakawa and Bembidion quadriimpressum (Motschulsky) (which may represent two separate entries), and (vi) B. nigropiceum (Marsham). The following lineages are widely separated within the subtribe Bembidiina: Orzolina is sister to the genus Ocys Stephens; subgenus Desarmatocillenus appears to be sister to all Bembidion Latreille excluding subgenus Phyla Motschulsky; B. laticeps + B. palosverdes is a clade in the Bembidion series; B. laterale is a member of the Princidium Motschulsky complex; B. umi and B. quadriimpressum are related to the Nearctic Clade of the Ocydromus Clairville complex; B. nigropiceum is sister to B. praeustum Dejean among sampled species. There are three separate lineages of ocean‐shore bembidiines that are known to prey on amphipods, and adults of these lineages [Bembidion (Desarmatocillenus), B. laterale, and B. mandibulare Solier] have unusually wide heads with long mandibles. Also common among independent lineages restricted to ocean shores are prominent front angles of the prothorax, larger numbers of setae on the elytral disc, a notable sinuation in the margin of each elytron near its apex, and short, wide mesotarsi. The reasons for the repeated evolution of these features are not evident. Our results also suggest that inland species of the Nearctic Clade may have arisen from an ocean‐shore ancestor. The close genetic similarities between the gravel river shore dwelling B. praeustum and the intertidal specialist B. nigropiceum suggest that the striking morphological adaptations of B. nigropiceum to the intertidal zone arose rapidly. We make one nomenclatural change: we resurrect the subgenus Lymneops Casey to accommodate B. palosverdes and B. laticeps.     

Olfactory response of three parasitoid species (Hymenoptera: Braconidae) to volatiles of guavas infested or not with fruit fly larvae (Diptera: Tephritidae)

The olfactory responses of the native parasitoids Doryctobracon areolatus (Szépligeti) and Asobara anastrephae (Muesebeck) and of the exotic parasitoid Diachasmimorpha longicaudata (Ashmead) to guava (Psidium guajava L.) infested or not with fruit fly larvae were evaluated. D. areolatus and D. longicaudata females responded to the odors of uninfested rotting guavas, although D. areolatus was also attracted to fruits at the initial maturation (turning) stage. The females of these species recognized the volatiles of guavas containing Ceratitis capitata (Wied.) larvae. However, in bioassays involving fruits with larvae of different instars, D. longicaudata females were not able to separate between fruits containing C. capitata larvae at the initial instars and larvae at the third instar. In the evaluations of volatiles released by guavas containing C. capitata and Anastrepha fraterculus (Wied.) larvae, the D. longicaudata females were oriented toward the volatiles of fruits containing both host species, but differed significantly from volatiles of guavas containing C. capitata larvae. The D. areolatus females also showed responses to both species, although with a preference for volatiles of fruits containing A. fraterculus larvae. The A. anastrephae females were oriented toward the odors of fruits infested with both fruit fly species. In the shade house, D. longicaudata females were oriented to volatiles of rotting fruits containing larvae or not, but could not significantly differentiate between hosts. D. areolatus females were not attracted toward fruits on the ground in the shade house, regardless of host, suggesting that this parasitoid does not forage on fallen fruits.