您好,欢迎来到尔游网。
搜索
您的当前位置:首页A New Species of Megarhyphus, an Interesting Discovery from the Lower Jurassic of England (Dip

A New Species of Megarhyphus, an Interesting Discovery from the Lower Jurassic of England (Dip

来源:尔游网
Vol 84 No.4 PP.693—695 ACTA GEOLOGICA SINICA(English Edition) Aug.20 1 0 A New Species of Megarhyphus,an Interesting Discovery from the Lower Jurassic of England(Diptera,Anis0p0didae) Krzemilfska EWA ,.Coram A.ROBERT and Krzemilfski WIESLAW l h ̄stitute rJ厂Systematics and Evolution fAniomals,Polish Academy ofSciences,Krakow,Poland 2 School ofHuman and Environmental Sciences,the UniversiO',Reading RG6 2A UK Abstract:The oldest representative of the genus Megarhyphus Kovalev(Diptera:Anisopodidae)is described from the Lower Jurassic(Sinemurian)of England.A summary of our knowledge of Jurassic Anisopodidae is given. Key words:new species,Megarhyphus,Anisopodidae,Olbiogastrinae,Diptera,Lower Jurassic,alula l lntl・OductiOn Recent AnisODOdidae are a small family comprising Issyk—Kul Lake in Kirghizia.dated as Sinemurian(Lower Jurassic).The next youngest are Mesorhyphus ilallus Handlirsch. 1 920 and Mesorhyphus zirzipanus Ansorge.1 996 from山e approximately l 2O species of worldwide distibutrion.Various Toarcian(Lower Jurassic)of Germany;Mesorhyphus areolatits Handlirsch,1 920 appears to be a synonym of Mesorhyphus tlanus taxonomic systems of the family co—exist today.It was divided into two subfamilies,Olbiogastrinae and Anisopodinae,by fAnsorge and Krzeminski.1 995).The youngest described f0ssil species of Olbiogastrinae is Mesorhyphus clav咖es Kovalev,1 990 from the Jurassic—Cretaceous boundary of Daya, east Hennig(1973).From the 1atter,Krivosheina(1986)separated the genus M、,cetobia into a monotypic family Mycetobiidae,and Amorim and Tozoni(1 994)raised the Olbiogastrinae to the rank of famil v Most authors currently acknowledge division into three Transbaikalia,Russia(Rasnitsyn and Quicke,2003). The Megarhyphus genus was hitherto known from tWO Astatic localities in Transbaikalia:Daya fMegarhyphus sophiae Kovalev, subfamilies:Olbiogastrinae,Anisopodinae,and Mycetobiinae(e. g.Woodley.1 989;Oosterbroek and Courtney,1995;Shcherbakov 1990; Jurassic-Cretaceous boundary) and Onokhoy et a1.,l995:Michelsen,1999;Grimaldi and Engel,2005),and this system is followed jn the present paper.Members of the subfamilies differ mainly in the wing venation and genitalia.An interesting evolutionary trait is the gradual reduction of spennathecae: Olbiogastrinae have three spermathecae, Mycetobiinae two.and Anisopodinae only one.Wing venation is similar in 0lbiogastrinae and Anisopodinae.while in the Mycetobiinae.the veins R2+3 and M2 are reduced.and the disca1 fd1 cell is open.The Olbiogastrinae subfamily comprises five recent genera:Carreraia Correa,1 947,lx ̄bogaster Phillippi, (Megarhyphus rectinervis Kovalev,1 990;Early Cretaceous). Kovalev(1990)mentioned an additionaI specimen from the Upper Jurassic of the Chimkent region of Kazakhstan,but without more precise data.Both described species are characterized by a subtriangular wing,with a greatly expanded anal lobe. The specimen described here is assigned to Megarh3phus on the basis of the similar wing shape and venation.It was collected from a fine—grained.1aminated 1imestone nodule in a marine mudstone sequence of the Lower Jurassic Lias Group exposed on the Dorset coast.southern England.With an estimated age of I 94 l 88 1.Olbiogaster 0sten—Sacken.1 886,Austrogaster Amorim and Tozoni.J 994.and Eogaster Amorim and Tozoni.1 994. The Anisopodomorpha belong to one of the oldest lineages of the Diptera.with n,mrhyphus blagoderm, Krzeminski and Krzeminska f20o31.a representative of Protorhyphidae,known Ma(Ogg et a1.,2008),it is approximately 50 Ma older than both congeners,and similr ian age to Mesorh3phus;tmtil now,the oldest known anisopodid. 2 Systematic Part Order Diptera Linn6,1 758 Family Anisopodidae Meigen,1 800 Subfamily Olbiogastinae Hennifg,1 973 Genus Megarhyphus Kovalev,1 990 from the Lower-Middle Triassic boundary of France. ProtorhvDhidae are ancestral to Anisopodidae and are fairly common among the Triassic and Jurassic Diptera.The Anisopodidae family had probably branched off by the basal Jurassic.and its oldest lineage is the Olbiogastrinae.represented by three Mesozoic genera:Mesorhyphus Handlirsch,1 938, Path3,rhx,phus Kovalev.1 986、and Megat‘hyphus Kovalev、l 990. The oldest species of Olbiogastfinae. and thus of the Anisopodidae.is Mesorhvphus rhaeticus Rohdendorf,J 962 from Megarhyphus amberae sp.nov. (Fig.1a-c) Diagnosis:Wing 4.8 mm long;anal portion expanded into subtriangular shape,widest approximately proximal third of wing. Corresponding author.E—mail:Krzeminska@isez.pan.krakow.pl Anal basal margin bears an alula and additional small lobe.R3 694 Megarhyphus Discovered from the Lower Jurassic of England(Diptera,Anisopodidae) Ewa et al (d) dMl+2 Fig.1.Megarhyphus amberae sp.nov.(Lower Jurassic;Dorset,UK). (a)Specimen(positive part);(b)region of discal cell magnified(negative part);(c)reconstruction;(d)Megarhyphus sophiae Kovalev(Kovalev,1 990,fig.108) almost straight;distance between tips of Sc and R l almost three 3 Discussion The species described herein differs from both younger congeners from Asia in wing shape and venation.The widest times the distance between the tips of Rl and R3:short cross—vein ml—m2 between M1 and M2.No free section of Ml+2 is present beyond the d cel1.The most similar species is Megarhyphus sophiae Kovalev;which differs in having an expanded anallobe portion of the wing in our species is shitfed more distally in closer to the wing base.more rounded in shape.only one smal1 comparison to Megarhyphus sophiae(Fig.1 d),in which the basalmost portion is also greatly rounded and not subtriangular. lobe(alula).and a free section M l+2 beyond the d cel1. Etymology:The new species name is dedicated to Amber,the eldest daughter of Robert Coram. The other species,Megarhyphus rectinervis Kovalev,1 990 is known only from a wing fragment and its exact shape is unknown. Both Asiatic species differ in venation,having a free section of MateriaI examined:Holotype Natural History Museum (London)number It 28447【LD/DIPT 2】,a single wing preserved in two parts f+,一).Brooki Bed,Shales—with—Beef Member, Charmouth Mudstone Formation,Lias Group(Lower Sinemurian, M l+2 beyond the d cell,while in Megarhyphus amberae sp.nov., such a section is absent and M 1 and M2 leave the d cell as separate veins(Fig.1 b). An intriguing character of our species is the two small lobes at Turneri zone,Brooki subzone),Monmouth Beach,Lyme Regis, Dorset。UK(national grid reference SY 334 9 l 4).Collected by R. A.Coram. Description:A well—preserved wing,4.8 mm long,1.9 mm the wing base.While one lobe(alula)is present in Anisopodomorpha,and also especially in the lower Brachycera, the wings with two lobes seem to be rare among the Diptera. The taxonomic status of the genus Megarhyphus is not certain. wide(Fig.1 a,c),of characteristic shape:anal portion is expanded into subtriangular shape,widest approximately proximal third of Kovalev(1990)classified it in Olbiogastrinae and remarked that the antennae are exceptionally short for this family.Such short antennae are characteristic of Anisopodinae,suggesting that Megarhyphus could belong within this subfamily.However,in the absence of other characters,such a placement would be premature. wing and anal basal margin bears an alula and additional small lobe.Sc long,terminating opposite three—quarters length of the d cell;R1 long,ending close to tip of R3;R3 almost straight; distance between tips of Sc and R l almost three times the distance between tips of R l and R3:Rs long;cross—vein卜m in middle of the d cell;R4+5 long and wavy,terminally arched to costal wing margin;d cell almost four times as long as wide.Short cross—vein Manuscript received Jan.4,20 1 0 accepted March 24,201 0 edited by Jiang Shaoqing m1一m2 between MI and M2 is present(this detailjs best seen on the negative part,Fig.1b).Ml almost twice as long as d cell;M4 leaves d eell in proximal tl1ird:cross.vein m__cu between M4 and Cu:A 1 strongly wavy in terminal section. Vo1.84 No.4 ACTA GEOLOGICA SINICA(English Edition) Aug.2010 695 References Amorim,D.S.,and Tozoni,S.H.S.,1 994.Phylogenetic and biogeographic analysis of the Anisopodoidea(Diptera, Bibionomorpha),with all area cladogram for intercontinental relationships.Revista Brasileira de Entomologia,38(3/4): 517—543. Ansorge J.,and Krzeminski,W.,l995.Revision of Mesorhyphus Handtirch.Eoptecia Handiirsch and Hetcrorhyphus Bode (Diptera:Anisopodomorpha,Bibionomorpha)from the Upper Llassie of Germany.Paldontologische Zeitschriif.69(1/2): 167-l72. Ansorge.J..1996.Insekten aus dem oberen Lias von Grilninen (Vorpommem,Norddeutschland).Neue Palaeontologische A扫向d,2 ,“玎 n,2:l—l 32(in German). Grimaldi.D.and Engel,M.S.,2005.Evolution of the Insects. Cambridge University Press,New York/Cambridge,755. Handlirsch,A.。1920.Palaeontologie(part)【=Lieferung 5】.In: Schroeder C.W.M.(ed.),Handbuch der Entomologie.Band III.G.Fischer.Jena:l l 7~208(in German). Hennig,W.,1973.Diptera(Zweifltigler).In:Helmcke,J.G., Stark,D.,and Wermuth,H..(eds.),HatMbuch der Zoologie. Eine Naturgeschichte der stdmme des Tierreichs.1K Band: Arthropoda一2.Hd!fte:Insecta Zweite Aulfage.2 tell: Spezielles.W.De Gruyter,Berlin,337(in German). Kovalev, V.G., 1 986. fInfraorders Bibionomorpha and Asilomorpha].In:Insects n the earh,Cretaceous ecosystems of Ⅵ,estern Mongolia. Joint Soviet — Mongolian Palaeontologic・a,Expedition.28:l25-54(in Russian). Kovalev,V.G..1990.Dipterans.Muscida.In:Rasnitsyn,A.P. (ed.、.Late Mesozoic insects of eastern Trnnsbaikalia.TrH Paleontologicheskogo nIstituta(,5 Aca Sci..239:l 23一l 77 (in Russian). Krivosheina.N.P.,1986.Family Anisopodidae.In:So6s,A.and Papp,L.(eds.)Catalogue of Palaearctic Diptera,Vo1.4. Akad6miai Kiad6.Budapest:330-332. Krzeminski.W.,and Krzeminska,E.,2003.Triassic Diptera: descriptions,revisions and phylogenetic relations.Ac ta ZOOlogica cracoviensia.46 fsupp1.一Fossil Insects):153—1 84. Michelsen,V、,1999.Wood gnats of hte genus Sylvicola(Diptera, Anisopodidae):Taxonomic status,family assignment,and review of nominal species described bv J.C.Fabricius dschr ̄ft voor Entomologie,l42:69-75, Ogg,J.G.,Ogg,G.,and Gradstein,F.M.,2008. Concise Geologic Time Scale.Cambridge:Cambridge University Press, l77. 0osterbroek,P.,and Courtney,G.,1995.Phylogeny of the nematocerous farallies of Diptera.Zoological Journal of the Linnean Society.11 5:267-3 l t. Rasnitsyn,A.P.,and Quicke,D.L.J.(eds.),2003.Histor.3'of nIsects.Kluwer Academic Pub1.Dordrecht/BOston,London 517pp. Rohdendorf,B.B..1962.Order Diptera.Flies.In:Rohdendoif,B. B.(ed.),Fundamentals of PaleontoIog3’.(Volume 9). Izdatel’stwo Akad.Nauk.MOSCOW:307-345 fin Russian). Shcherbakov,D.E,Lukashevich,E.D.,and Blagoderov,V.A, 1995.Triassic Diptera and initial radiation of the order. Internationaf Journaf of Dipterologicaf Research,6(2 :75— 115. Woodley,N.E.,1989.Phylogeny and classiifcation of the “orthorrhaphous”Brachycera.In:McAlpine,J.E.,and Wood D.M.(eds.),Manual fo Nearctic Diptera,Vo1.3.Agriculture Canada Monograph 32.Ottawa:1 37 1一l 396. 

因篇幅问题不能全部显示,请点此查看更多更全内容

Copyright © 2019- axer.cn 版权所有 湘ICP备2023022495号-12

违法及侵权请联系:TEL:199 18 7713 E-MAIL:2724546146@qq.com

本站由北京市万商天勤律师事务所王兴未律师提供法律服务