Two species of Ichneumonidae from Tristan da Cunha and Nightingale Islands, South Atlantic (Hymenoptera)

Transcription

1 Mitt. Münch. Ent. Ges München, ISSN Two species of Ichneumonidae from Trian da Cunha a Nightingale Islas, Sou Atlantic (Hymenoptera) Klaus HORSTMANN Abract Two species of Ichneumonidae (Hymenoptera) from Trian da Cunha a Nightingale Islas, Sou Atlantic, are described: Ichneumon insulator sp. n. a Meloboris helmia (HOLMGREN). Some remarks on Ichneumon unicinctus BRULLÉ are added. Introduction In a recent biological survey of Trian da Cunha a Nightingale Islas, a number of parasitic Hymenoptera were collected by Chriine HÄNEL a Jeremy GREEN. Two species of Ichneumonidae were sent to me for determination. One of em proved to belong to Meloboris helmia (HOLMGREN), a species know only from e original description (HOLMGREN 1868: 417). The oer is apparently an uescribed species of Ichneumon LINNAEUS. Bo species are described here. The fauna of e Trian da Cunha Archipelago was revised by HOLDGATE (1965), who mentioned one species of Ichneumonidae (Phygadeuon spec. from Trian da Cunha). Material of is taxon could not be traced. Ichneumon insulator sp. n. Holotype ( ): Nightingale Isla '095"S; 12 28'470"W; 03 April Collector Jeremy GREEN, Ea laing area Coaal boulders + Tussock + Shack developments. Inside hut, alive (Natural Hiory Museum, Loon). Paratypes (2 ): Trian da Cunha '44"S; '53"W; 2270 ft. 15 Feb Leg. C. HÄNEL, On e rim, we of patches. Above Molly Gulch, below Daylies Hill. Malaise trap. Blechnum palmiforme grassla mix. (1 Natural Hiory Museum, Loon; 1 Iziko Museums, Cape Town). The new species belongs to e species group A of HILPERT (1992: 45), but cannot be associated wi one of e subgroups characterized for European species. In Europe, species of at group parasitize pupae of Noctuidae hidden uer moss or in e soil (HINZ & HORSTMANN 2007: 60). The species is closely related to I. unicinctus BRULLÉ, a species known from Seychelles, Réunion, Mauritius a Madagascar (HEINRICH 1967: 492), a also a parasitoid of Noctuidae. Female: Head wi punctation on a smoo backgrou. Temples diinctly conricted behi e eyes, 0.7 times as long as e wid of e eye (seen from above), tangential lines on eyes a temples intersect on e scutellum (Fig. 1). Diance between eye a lateral ocellus 1.2 times as long as e longe diameter of a lateral ocellus. Malar space 0.8 times as long as basal wid of a maible. Genal carina joining e oral carina diant from e base of e maible, bo carinae low. Maible sleer, lower maibular too diinct, much shorter an upper too. Clypeus slightly roued basally, flat apically, wi some small punctures basally, few large punctures basally a medially, a a line of very small punctures subapically, wiout longitudinal riae. Apex of clypeus in, sharp, almo not roued forwards medially. Face wi raer fine a dense or very dense punctures, partly wi transverse wrinkles. Frons, vertex a temples for e greater part wi very dense a fine punctures, partly rugose. Temples wi disperse punctation ventrally. 31

2 Fig. 1-4: Ichneumon insulator sp. n. (holotype ). 1. Head from above. 2. Base of antenna. 3. Area superomedia. 4. Popetiole a base of 2 garal tergite. Fig. 5-7: Meloboris helmia (HOLMGREN) (holotype ). 5. Head from above. 6. Areolet. 7. Area superomedia. Flagellum wi 36 segments, out, slightly fusiform, flattened on e uerside medially a subapically, truncate a almo not attenuated apically, 1 segment (annellus excluded) 1.9 times, 7 segment 1.0 times, shorte a wide segment 0.5 times, penultimate segment 0.73 times as long as wide (Fig. 2). Thorax for e greater part wi very dense punctation on a smoo backgrou, partly rugose-punctate. Pronotum laterally a mesopleurum partly rugose. Scutellum dispersely punctate medially. Speculum densely punctate. Hi coxa wi a diinct oval scopa (area wi conspicuous a very dense pilosity) ventrally, wi fine a very dense punctures beside e scopa, dense a raer fine punctures in oer parts, a a few additional large punctures. Legs out, hi femur 3.7 times as long as high, wi dense a fine rd punctation all over its outer side. Tarsi of front a mid legs enlarged, 3 segments of front a mid tarsi 1.0- rd 1.1 times as long as wide. Hi tarsus not much enlarged, 3 segment 1.7 times as long as wide. Propodeum finely a very densely rugose a rugose punctate. Area superomedia 1.3 times as long as wide, wi almo parallel sides, coulae lacking (Fig. 3). Area poica divided into ree parts by fine longitudinal carinae, e lateral parts more coarsely rugose an e middle part. Middle part of e popetiole 1.25 times as wide as a lateral part, somewhat raised, wi about 20 fine longitudinal riae a wi a few additional fine punctures. Lateral parts for e greater part wi longitudinal wrinkles. 2 garal tergite wi fine a very dense punctures, a wi very fine longitudinal riae anteriorly between e garocoeli, some of ose riae exteing almo to e middle of e tergite. Interspace between e garocoeli 2.4 times as wide as e wid of a garocoelus. Garocoelus diinct, not deeply depressed, wi 32

3 about eight longitudinal ridges. Thyridum diinct, oblique (Fig. 4). Middle a poerior tergites wi very dense a fine punctures a very dense a fine pilosity, almo velvety. Gaer slightly attenuated poeriorly. Subgenital plate short. Ovipositor slightly projecting beyo e tip of e gaer. Integument colour for e greater part black. Palpus yellowish brown. Maible tinged wi brown. rd Clypeus a inner orbits tinged wi reddish brown. Scape, pedicellus a 1 to 3 flagellar segments dark yellowish brown, 4 to 7 segments blackish, 8 to 11 segments blackish dorsally, dark yellowish brown ventrally, dial segments black. Scutellum yellow. Tegula a basal sclerites of wings dark yellowish brown. Wings hyaline, igma pale yellowish brown. Legs for e greater part dark yellowish brown. Coxae partly tinged wi black. Dial half of hi tibia a all of hi tarsus black. 1 garal segment dark yellowish brown, partly tinged wi black. 2 tergite brownish black anteriorly a medially, e poerior 0.3 yellowish brown. The following tergites black, eir poerior edges narrowly yellowish brown. 7 tergite dark yellowish brown. Pilosity whitish. Head 2.3 mm wide. Thorax 4.2 mm long (mesoscutum to propodeum), 1.76 mm wide (mesoscutum). Front wing 8.0 mm long. 1 garal tergite 2.1 mm long. Popetiole 0.71 mm long, 1.17 mm wide. 2 tergite 1.76 mm long, 2.4 mm wide. Body leng (wiout ovipositor) 11.4 mm long. Male: Malar space 0.55 times as long as basal wid of a maible. Flagellum wi segments, wi tyloids on e segments 6-15 or Large tyloid 0.64 times as long as flagellar segment, 5.0 times as long as wide, slightly widened medially. In oer sculptural characters similar to e. Integument colour für e greater part black, wi extensive light yellow markings. Yellow are: palpi, maible (except tee), clypeus, face, frontal orbit, a large ventral ripe on e outer orbit (but malar space a a narrow ba on e gena black), ventral half (or more) of scape a pedicellus, collum dorsally a wi a small ripe laterally, pronotum wi a long dorsal ripe poeriorly, tegula, basal sclerites of wings, subalar prominence, scutellum, poscutellum, a narrow poerior ripe on metapleurum, front a mid legs, dorsal part of hi coxa, hi trochanter a trochantellus, basal 0.6 of hi tibia, basal 0.8 of hi basitarsus, poerior 0.7 of propodeum, poerior 0.7 of popetiole, anterior, lateral a poerior edges of 2 rd garal tergite, lateral a poerior edges of 3 tergite, poerior edges of 4 a 5 tergites. Base of flagellum reddish brown ventrally (up to e 12 segment). Wings hyaline, igma pale yellowish brown. Femora, tibiae a tarsi of front a mid legs partly tinged wi light red. Hi femur reddish brown proximally, black dially (to a variable extent). 6 a 7 garal tergites wiout yellow markings, slightly tinged wi brown. Subgenital plate black. Genital clasper brownish proximally, yellowish brown dially. Pilosity whitish. Ichneumon unicinctus BRULLÉ This species is revised a described by HEINRICH (1967: 492). The differs from I. insulator by: Clypeus wi dense or very dense punctation. Maible slightly inflated subapically. Flagellum wi segments, e 4 or 5 segment about as long as wide. Popetiole less extensively riate. Wings diinctly infuscated, igma black. Mid a hi legs black, tibiae slightly tinged wi brown. 2 garal tergite wi a narrow whitish to reddish ba poeriorly. The is raer poorly marked wi yellow on head, orax a legs (see description by HEINRICH). In addition it differs from I. insulator by: Clypeus wi very dense punctation. Flagellum wi segments. Popetiole less extensively riate. 4 a 5 garal tergites wiout yellow markings, but 6 a 7 tergites wi large yellow spots dorsally. HEINRICH mentions 2 from Madagascar wi extensive yellow markings, which he tentatively places to unicinctus, but does not describe e characteriics used here to diinguish insulator a unicinctus. Material: 1 Mauritius, ex Sesamia calamiris HAMPSON (Noctuidae) (Natural Hiory Museum, Loon); 1, 1 Antananarivo, Tananarive Prov., Madagascar (American Entomological Initute, Gainesville); 1, 1 Bekily, Madagascar (Muséum National d Hioire Naturelle, Paris); 2 Tananarive, Madagascar (Paris); 1 Bekily, Madagascar (Loon); 1 Périnet, Madagascar (Zoologische Staatssammlung München, Munich). 33

4 Meloboris (Nepiera) helmia (HOLMGREN) Holotype ( ): Cap. B. Spei. (Cape of Good Hope, Sou Africa), Victorin. Type, L. Helmia HGN. (Naturhioriska Riksmuseet, Stockholm). This species was known up to now only from e holotype. It belongs to e subgenus Nepiera FÖRSTER (HORSTMANN 1970: 81) a is very similar to e Palaearctic species Meloboris collector (THUNBERG). The latter differs by e colour of e hi coxa (completely black). M. collector parasitizes larvae of several species of Noctuidae (TISCHLER 1966: 73; AUBERT et al. 1984: 226; ŠEDIVÝ 1986: 17). Female: Head for e greater part coriaceous a dull. Temples very short a rongly conricted behi e eyes, 0.55 times as long as e wid of an eye (seen from above), tangential lines on eyes a temples intersect shortly behi e centre of e mesoscutum (Fig. 5). Diance between eye a lateral ocellus 1.15 times as long as e longe diameter of a lateral ocellus. Face 0.85 times as wide as frons. Eye scarcely emarginate beside e antennal socket. Malar space 0.6 times as long as e basal wid of a maible. Genal carina joining e oral carinae diinctly diant from e base of e maible, bo carinae low. Lower margin of maible diinctly lamelliform, upper too slightly larger an lower too. Clypeus diinctly roued, wi some fine punctures subapically, its apex sharp, truncate medially. Vertex a temples finely coriaceous, slightly shining, very fine punctures hardly discernible. Flagellum wi segments, sleer, filiform, 2 segment 3.3 times, penultimate segment 1.3 times as long as wide. Thorax coriaceous, dull. Lateral part of pronotum wi short riae poeriorly. Epomia fine. Notaulus very weakly iicated. Prescutellar groove smoo. Scutellum wi lateral carinae only anteriorly. Speculum finely coriaceous, slightly shining. Speculum a impression in front of e speculum wiout pilosity, oer parts of e orax wi diinct fine pilosity. Prepectal carina complete, low. Popectal carina interrupted subventrally in front of e mid coxae. Areolet large, narrowly sessile or pointed, wie 2 recurrent vein at or shortly diad of e middle (Fig. 6). Nervulus diinctly pofurcal. Nervellus vertical, not visibly intercepted (sometimes slightly reclivous a slightly intercepted). Legs sleer, hi femur 5.7 times as long as high. Hi claws short, wi two short pectinate tee basally. Propodeum coriaceous, wi conspicuous dense a fine white pilosity. Area basalis a area petiolaris surroued by diinct carinae, lateral carinae of e area superomedia iiinct a partly covered wi wrinkles. Area basalis sessile, slightly longer an wide. Area superomedia about 2.5 times as long as wide (sometimes narrower), wi coulae in front of e middle, e latter partly reduced (Fig. 7). Area petiolaris flat, wi some longitudinal wrinkles. Propodeal spiracle raer large, closer to e pleural carina an its longe diameter. 1 a 2 garal tergites coriaceous a dull, poerior tergites finely coriaceous a shining. Petiole laterally wi dorsal a ventral longitudinal carinae but wiout glymmae. Popetiole roued dorsally a laterally, wi complete lateral carinae, spiracles scarcely protruding. Thyridium diinct, large, its diance to e anterior edge of e 2 tergite 1.5 times as wide as its longe diameter. Poerior edges of 6 a 7 garal tergites not emarginate dorsally. Ovipositor diinctly projecting beyo e tip of e gaer, ovipositor shea 0,7 times as long as e 1 garal tergite. Integument colour for e greater part black. Palpi, maible (tee brown), scape a pedicellus ventrally, proernum ventrally, upper hi corner of pronotum, tegula, basal sclerites of wing, coxae, trochanters a trochantelli whitish (e white marks more exteed in e holotype). Hi coxa wi a small blackish basal mark (lacking in e holotype). Femur, tibia a tarsus of front leg whitish yellow. Mid femur yellowish red. Mid tibia whitish, brown apically. Mid tarsus blackish, its basitarsus broadly whitish basally. Hi femur light reddish brown ventrally a on e inner side, wi a blackish ripe dorsally. Hi tibia whitish basally a ventrally, wi black dorsal marks subbasally a apically, usually wi a blackish dorsal ripe also medially (is ripe lacking in e holotype). Hi tarsus black, basitarsus wi a small white mark basally. Pteroigma dark brown (light brown in e holotype, perhaps faded). Poerior edges of 2 to 8 garal tergites broadly whitish, lateral edges of poerior tergites whitish, sometimes also e popetiole whitish poeriorly. Head 0.93 mm wide. Thorax 1.49 mm long (mesoscutum to propodeum), 0.61 mm wide (mesoscutum). Front wing 3.2 mm long. 1 garal tergite 0.66 mm long. Popetiole 0.24 mm long, 0.23 mm wide. 2 tergite 0.63 mm long, 0.35 mm wide. Ovipositor shea 0.39 mm long. Body leng (wiout ovipositor) about 3.9 mm. The measurements were taken from 1 from Nightingale Isla; e holotype from e Cape of Good Hope is larger by a factor of about

5 Male: Flagellum wi about 30 segments. In oer characters similar to e. Material: 1 Cape of Good Hope (Naturhioriska Riksmuseet, Stockholm); 2, 2 Johannesburg (American Entomological Initute, Gainesville); 2, 7 Nightingale Isla a 1, 3 Trian da Cunha, collector Chriine HÄNEL (1, 2 Iziko Museums, Cape Town, 1, 2 Natural Hiory Museum, Loon, 1, 5 Natural Resources Department, Trian da Cunha, 1 Coll. Hormann). Acknowledgements I am iepted to Chriine HÄNEL (Stellenbosch), Gavin BROAD (Natural Hiory Museum, Loon), Simon VAN NOORT (Sou African Museum, Iziko Museums, Cape Town) a Mark SHAW (National Museums of Scotla, Edinburgh) for collecting a sorting e material from e Sou Atlantic islas a seing it for udy, a to Hege VÅRDAL (Naturhioriska Riksmuseet, Stockholm), Claire VILLEMANT (Muséum National d Hioire Naturelle, Paris) a David WAHL (American Entomological Initute, Gainesville) for seing types a oer material for comparison. The field work of Chriine HÄNEL was supported by e Darwin Initiative a e Royal Society for e Protection of Birds. Zusammenfassung Zwei Arten der Ichneumonidae (Hymenoptera) von den Inseln Trian da Cunha u Nightingale im Südatlantik werden beschrieben: Ichneumon insulator sp. n. u Meloboris helmia (HOLMGREN). Einige Bemerkungen zu Ichneumon unicinctus BRULLÉ si angefügt. References AUBERT, J.-F., J. HALPERIN & D. GERLING 1984: Les ichneumonides d Israel. Entomophaga 29, HEINRICH, G. 1967: Synopsis a reclassification of e Ichneumoninae Stenopneuicae of Africa sou of e Sahara (Hymenoptera). Vol. III. Synopsis of e Ichneumonini: Subtribes Ichneumonina a Amblytelina. State College Press, Farmington, pp HILPERT, H. 1992: Zur Syematik der Gattung Ichneumon LINNAEUS, 1758 in der Wepalaearktis (Hymenoptera, Ichneumonidae, Ichneumoninae). Entomofauna, Suppl. 6, HINZ, R. & K. HORSTMANN 2007: Über Wirtsbeziehungen europäischer Ichneumon-Arten (Insecta, Hymenoptera, Ichneumoniae, Ichneumoninae). Spixiana 30, HOLDGATE, M. W. 1965: The fauna of e Trian da Cunha Islas. Phil. Trans. R. Soc. Loon (B) 249, HOLMGREN, A. E. 1868: Hymenoptera. In: Kongliga svenska fregatten Eugenies resa omkring jorden. Vol. 1, Zoologi. Part 1, Insecta. P. A. Noredt, Stockholm, pp HORSTMANN, K. 1970: Bemerkungen zur Syematik einiger Gattungen der Campopleginae (Hymenoptera, Ichneumonidae). NachrBl. Bayer. Ent. 19, ŠEDIVÝ, J. 1986: The hos of ichneumon flies in Europe (Hymenoptera, Ichneumonidae). Acta ent. bohemoslov. 83, TISCHLER, W. 1966: Pflanzenengel als Überwinterungsellen für Tiere der Agrarlaschaft. Faun.-Ökol. Mitt. (Neumüner) 3, Auors address: Dr. Klaus HORSTMANN Lehruhl Zoologie III Biozentrum, Am Hubla D Würzburg, Germany 35