Aphaereta ceratitivora sp. n. (Hymenoptera, Braconidae), a new parasitoid of Ceratitis capitata (Wiedemann) (Diptera, Tephritidae) from the Azores

Abstract A new gregarious larval-pupal endoparasitoid of Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) is described and illustrated: Aphaereta ceratitivora sp. n. (Braconidae: Alysiinae: Alysiini).


Introduction
In recent years interest in the parasitoid Hymenoptera has grown as a result of the increasing demand for biological methods for pest control and their possible use as natural enemies. The Braconidae are the second largest family of this order, the major-ity of species are primary parasitoids of immature stages of Lepidoptera, Coleoptera and Diptera (Sharkey 1993).
Ceratitis capitata (Wiedemann, 1824) (Diptera: Tephritidae) or Mediterranean fruit fly (Medfly) is a pest that causes substantial economic losses in the Mediterranean fruit production due to their high dispersal ability and ecological plasticity (Liquido et al. 1991;Gillani et al. 2002). In Azores (Portugal) a survey was done to see if there were possible candidates for the control of C. capitata, before considering the introduction of exotic species, that can cause adverse effects on the native parasitoids and non-target species (Oliveira et al. 2008).
From two parasitized pupae of C. capitata collected in São Miguel Island (Azores, Portugal) emerged in total 12 adult parasitoids, belonging to a new species of the genus Aphaereta Foerster, 1862 (Alysiinae: Alysiini). Six adult parasitoids emerged per pupa; rearing in the lab resulted in four parasitoids per host pupa at 20°C (the optimum temperature for development). The subfamily Alysiinae, with 2321 catalogued species worldwide (Yu et al. 2012) has a prominent position within the Braconidae family (van Achterberg 1993, Dolphin andQuicke 2001) and consists of the tribes Alysiini and Dacnusini. The species of this subfamily are endoparasitoids of dipterous larvae, with oviposition into the egg or the larva of the host and emergence from the host puparium. Wharton (2002) used this character, along with the possession of exodont mandibles, to define the subfamily. Almost all Dacnusini are parasitoids of leaf-and stem-mining dipterans, usually Agromyzidae (Wharton 2002), but Alysiini attacks a wide range of dipterous hosts from at least 20 different families (Wharton 1980).
Diagnosis. Antenna of ♀ with 18-20 segments and 1.1-1.2 times as long as fore wing; pedicellus yellowish-brown, not contrasting with scapus; third antennal segment of ♀ dark brown or brown basally and comparatively slender (Fig. 6); outer side of fourth antennal segment of ♀ straight or nearly so (Fig. 6); fourth-seventh antennal segments of ♀ moderately shiny and dark brown; ventral convex area of side of pronotum moderately narrow and yellowish-brown; medio-posterior depression of mesoscutum absent; wing membrane slightly infuscate; axillar depression narrow to medium-sized and smooth; tegulae brown or dark brown, darker than fore femur; ventrally hind basitarsus narrowly acutely protruding postero-ventrally; hind tibia distinctly setose baso-dorsally; hind basitarsus moderately slender and often more or less infuscate; tarsal claws narrow (Fig. 7); median carina of propodeum in lateral view hardly protruding and narrowly lamelliform (Fig. 12); first metasomal tergite strongly widened posteriorly, medially densely and finely rugulose and dark or pale brown (Fig.  11); setose part of ovipositor sheath 0.6 times as long as metasoma and 0.7-0.8 times as long as hind tibia; length of fore wing 1.6-2.4 mm and of body 1.6-2.2 mm.
Distribution. Portugal (Azores); most likely also France, but no material available for study (see below).
Etymology. From the generic name of its host (Ceratites) and "voro" (Latin for "devour"), because it is devouring this host.
Notes. Similar to the gregarious Nearctic A. pallipes (Say, 1829), but this species is a parasitoid of other families and has the setose part of the ovipositor sheath about as long as the metasoma and longer than the hind tibia. The Mediterranean fruit fly has been reported as host of A. minuta (Nees, 1911) from South France (Ghesquière 1950, Martin 1952, Narayanan and Chawla 1962, but this is most likely a misidentification. A. minuta is very similar, but differs in having the hind basitarsus slenderer (Fig. 21) (less so in A. ceratitivora; Fig. 7), the antennal segments of ♀ up to 22 (up to 20 segments), the axillar depression wide and finely crenulate (comparatively narrow and smooth), clypeus low basally (steeply elevated), the first tergite less widened posteriorly (more widened posteriorly; Fig. 11)), the tegulae and fore femur similarly coloured (tegulae darker than fore femur) and gregarious parasitoid of dipterous larvae in dung and rotting organic matter; e.g., Scatophaga species in rotting seaweed, and Sarcophaga species in human excrements and rotting Sepia species (gregarious parasitoid of C. capitata in fruits).

1
Lateral carina of mesoscutum absent in front of tegulae (Fig. 14a); ovipositor sheath very aberrantly shaped, widened submedially and up curved apically (Fig. 15); labial palp with 2 segments (Fig. 14b) (Fig. 23); hind femur less bristly setose and more slender in lateral view (Fig. 3)  Tegulae brown or dark brown, darker than fore femur; hind basitarsus less slender ( Fig. 7; about 4.5 times as long as its maximal width); axillar depression narrow to medium-sized and smooth (Fig. 13); ventral convex area of side of pronotum comparatively narrow (Fig. 12) Note. Similar to the Nearctic A. pallipes (Say, 1829), but this species is a gregarious parasitoid of other Diptera families and has setose part of ovipositor sheath about as long as metasoma and longer than hind tibia. -Tegulae yellowish-brown, similar to colour of fore femur; hind basitarsus comparatively slender (Figs 20, 21; about 5 times as long as its maximum width); axillar depression large triangular; ventral convex area of side of pronotum comparatively wide (Fig. 24)