Dtsch. Entomol. Z. 60 (1) 2013, 53–58 / DOI 10.1002/mmnd.201300006
Alena Nav s, 1916 – the dethroned genus and Alena (Aztekoraphidia) michoacana sp. n. from Mexico (Neuropterida: Raphidioptera: Raphidiidae)
Ulrike Asp ck*,1,2 and Horst Asp ck3
1 Naturhistorisches Museum Wien, Zweite Zoologische Abteilung, Burgring 7, 1010 Vienna, Austria 2 Department of Integrative Zoology, University of Vienna, Althanstraße 14, 1090 Vienna, Austria 3 Institute of Specific Prophylaxis and Tropical Medicine, Medical Parasitology, Medical University of Vienna (MUW), Kinderspitalgasse 15, 1090 Vienna, Austria
Abstract
Received 11 December 2012 The new concept of the genus Alena, in which it is no longer the sister group of all Accepted 13 December 2012 other Raphidiidae but only of the Palaearctic clade, is presented and discussed. A. (Az- Published 22 May 2013 tekoraphidia) michoacana sp. n. is described and differentiated from other species based on the male holotype. In Alena the so-called basal sclerites which connect the gonocoxites 9 with the gonapophyses 9 are homologized with the gonangulum hitherto Key Words only ascribed to female genitalia. The homology is based on sclerites known from Ma- chilidae in both sexes. The hypothesis that the gonapophyses 9 are terminally amalga- New species mated into a complex, which comprises the fused gonocoxites, gonostyli, and gonapo- Phylogeny physes 10, is corroborated by A. michoacana sp. n., in which an intermediate state of Taxonomy this connection is evident. The geographic restriction of Alena species to high altitudes Genital sclerites of Mexico (and in two species – to the southernmost parts of the USA) is interpreted Gonangulum as a radiation following multiple vicariance events after the arrival of a more general- Biogeography ized stem species.
Introduction unexpected and surprising result represents a manifold challenge involving not only phylogeny, but also bio- For many years and until recently the genus Alena was geography and particularly the morphology of the geni- unquestionably regarded as the sister to all other extant tal sclerites. Raphidiidae (H. Asp ck et al. 1991; U. Asp ck & H. Alena is a small genus currently comprising nine Asp ck 1996; H. Asp ck 1998; H. Asp ck et al. 2001; species (U. Asp ck & H. Asp ck 1996, U. Asp ck & H. Asp ck & U. Asp ck 2007). With respect to the bi- Contreras-Ramos 2004). The discovery of these species zarre appearance and shape of the genital sclerites Ale- spanned about 110 years, Alena australis (Banks, 1895) na is the most eccentric genus of the Raphidiidae – a being the first and Alena horstaspoecki U. A. & Con- fact which supported this assumption. Moreover, the treras-Ramos, 2004, the latest. Snakeflies are among geographic restriction of the distribution to the south- the rarest insects in Mexico, and, in particular, every ernmost parts of North America (predominantly Mexi- record of a specimen of Alena merits attention. Over co) was another supporting argument. the past one hundred years less than 50 imagines of However, a molecular study on the phylogeny of the Alena have been collected. Snakeflies from Mexico are Raphidiidae (Haring et al. 2011) revealed that rather thus extremely seldom in collections, even of the lar- than Alena the distinctly less spectacular genus Agulla, gest institutions. The finding of any new species of which is also confined to the Nearctic and distributed Alena was and will always remain an exciting event. throughout the western parts of North America, is the Thus, the description of Alena (Aztekoraphidia) mi- sister to all other Raphidiidae. In that study, Alena choacana sp. n. presented in this paper is an entomolo- emerged as sister to all Palaearctic Raphidiidae. This gical highlight.
* Corresponding author, e-mail: [email protected]
# 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 54 Aspo¨ck,U.& Aspo¨ck,H.: Alena and A. michoacana sp. n. from Mexico (Raphidioptera)
Results Head “triangular”, black with a fine sculpture, and with a dark brownish median fascia, clypeus and labrum Alena Nav s, 1916 ochre brownish. Antennae: scapus, pedicellus and basal third of flagellomeres yellowish, flagellum otherwise Alena Nav s, 1916 (original description) (type species Raphidia dis- dark brownish. Pronotum: laterally with broad yellow tincta Banks, 1911): H. Asp ck et al. 1991, U. Asp ck et al. margin, anterior half brownish, caudal half dark brown- 1994, U. Asp ck & H. Asp ck 1996, U. Asp ck & Contreras-Ra- mos 2004. ish with lighter brownish pattern. Legs: predominantly yellow, third coxae brownish. Wings: membrane hya- The genus comprises three subgenera: line, venation predominantly ochre brownish, subcosta Alena s. str. (with one species: A. distincta (Banks, darker; basal part of Media anterior (Ma) in hind wing 1911)), Mexicoraphidia U. A. & H. A. 1970 (with one as a crossvein. Pterostigma yellow, above the middle of species: A. americana (Carpenter, 1958)), and Aztekor- the first pterostigmal cell, with one vein crossing. Ab- aphidia U. A. & H. A., 1970 (with seven species: A. domen: tergites and sternites blackish brown, the latter caudata (Nav s, 1914), A. infundibulata H. A. & U. A. caudally broad yellowish. Genital segments conspicu- & Rausch, 1994, A. schremmeri H. A. & U. A. & ously enlarged and yellowish. Rausch, 1994, A. minuta (Banks, 1903), A. australis Male genital segments (Figs 1, 3–5): Sternite of seg- (Banks, 1895), A. tenochtitlana U. A. & H. A., 1978, ment 8 only slightly shorter than tergite; tergite 9 trape- A. horstaspoecki U. A. & Contreras-Ramos, 2004). ziform, dorsally with median suture; gonocoxites 9 A. distincta and A. minuta have also been found in forming huge plates with a digitiform apex; gonostyli southwestern parts of the USA, all other Alena species large and stout, apically falcate; sternite 9 indistinct; are recorded only from Mexico. distinct large basal sclerites between gonocoxites 9 and gonapophyses 9 (hypovalva); paired gonapophyses 9 Alena (Aztekoraphidia) michoacana sp. n. terminally connected with huge paired sclerites consist- ing of a domed plate with dorsal and ventral processes. Derivatio nominis. The specific epithet is derived from This complex structure is interpreted as the fused gono- Michoac n, that state of Mexico, where the new species coxites, gonapophyses, and gonostyli 10 (called para- was discovered. The name is a noun of feminine gender meres); hypandrium internum huge; ectoproct (tergites in the nominative and an apposition to the name of the 10 þ 11) lacking distinct trichobothria, consisting of a genus. dorsal plate and lateral arms, which are terminally Material studied. Holotype, male: “Carapan, Michoa- rounded. can, Mex. VII-1-63 /Collr: W. A. Foster/Berkeley, v.C.” Differentiation. According to the morphology of the [19 5103600 N, 102 0201000 W, ca. 2000 m], in collection gonocoxites 9 and the gonostyli 9 Alena michoacana of the Californian Academy of Sciences. sp. n. clearly belongs to the subgenus Aztekoraphidia. Morphology (Figs 1, 3–5). A small tender species, From the three Alena species which have the Ma in the length of forewing 8 mm, habitus dominated by yellow hind wing as a longitudinal vein – A. (M.) americana, elements (pterostigma, legs and genital segments). A. (A.) caudata, and A. (A.) horstaspoecki – A.(A.) mi-
Figure 1. Habitus of Alena (Aztekoraphidia) michoacana sp. n., holotype, male. Arrow indicates the basal piece of Media anterior in the hind wing. 2. Original labels of Alena (Aztekoraphidia) michoacana sp. n., holotype, male.
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Figures 3–5. Alena (Aztekoraphidia) mi- choacana sp. n., holotype. Male genital segments, dorsal (3), ventral (4), lateral (5). e – ectoproct; bs – basal sclerite (interpreted as homologous to the female gonangulum); gx9 – gonocoxite 9; hi – hypandrium inter- num; hv – hypovalva (gonapophyses 9); p – fused parameres (complex of fused go- nocoxites, gonapophyses and gonostyli 10); s – gonostylus; S – sternite; T – tergite. choacana sp. n. can be separated eidonomically since assign one of the female specimens to A. michoacana. the Ma in the hind wing is a crossvein. A. (A.) distinc- Clarification would require finding further male speci- ta, A. (M.) americana, and A . (A.) caudata can also be mens, which may not occur in the immediate future. separated eidonomically since the pterostigma has an Distribution. The distribution of A. michoacana sp. n. apical vein. A. (A.) michoacana can be separated from is almost certainly restricted to high altitudes within a all other Alena (Aztekoraphidia) species by the shape small area of southwest Mexico, possibly only in the of the distinctly monstrous “parameres” (fused gono- state of Michoac n. coxites, gonostyli, and gonapophyses 10) which appear as simple acute apices of the gonapophyses 9 (hypoval- Discussion. In connection with the dethronement of va) in A. (A.) minuta, A. tenochtitlana, A. infundibulata Alena as the sister group of all other Raphidiidae and and A. schremmeri or have ventrally protruding bottoms the shift of Agulla to the most basal position in our in A. australis. There is no particularly close relation- molecular analysis (Haring et al. 2011), the morpholo- ship to any of the other Aztekoraphidia species. gical, phylogenetic and biogeographical implications Female unknown. In addition to the male holotype of need to be addressed. A. michoacana sp. n., two female specimens (coll. TAMU, kindly provided by Dr. John Oswald, Texas A&M University, College Station, USA) are available Morphological implications from Michoac n (Fig. 6), each of them representing a different species, and none of them can be clearly as- First: The question arises what is the nature of the so- signed to the male. It would therefore be confusing to called basal sclerites (Figs 4, 5)? In Alena, they connect
# 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim museum-dez.wiley-vch.de 56 Aspo¨ck,U.& Aspo¨ck,H.: Alena and A. michoacana sp. n. from Mexico (Raphidioptera)
Figure 6. Distribution of Alena in Mexi- co. The map shows not only the records of the described 10 species but also those of the unidentified females. There is no doubt that the unidentified speci- mens, at least in part, represent new spe- cies. Most records are based on single specimens. From the 10 species of Ale- na, only two – A. distincta and A. minu- ta – have been found outside Mexico in the USA, namely in California (A. dis- tincta) and Arizona, New Mexico, south- ern Utah and southern Colorado (A. min- uta). the anterior basal part of the gonocoxites 9 with the In male machilids (Bitsch 1974b, Fig. 1B) the follow- basal parts of the gonapophyses 9 and are very distinct ing sclerites are present: a sclerotized sternite 9, gonapo- and characteristic. In Agulla they are not visible, how- physes 9, the homologous sclerites 1) and 2); however, ever, they can be traced back in the basal globular ele- the precoxal sclerite 3) is absent (sclerite numbers corre- ments of the gonocoxites 9 known from Palaearctic spond to those given above in the description of the fe- species. These basal sclerites are either an ancient ele- male). This infers that there is a comparable sclerite in ment which has been lost in Agulla, or they are a new the male which is homologous to the gonangulum of the invention and a synapomorphy of Alena þ the Pa- female, despite the fact that the terminus gonangulum is laearctic clade. We consider that the basal sclerites are used exclusively for the female. In male Raphidiidae of an ancient element and thus belong to the ground pat- the genus Alena, the so-called basal sclerites are appar- tern of the stem species of Raphidiidae. Although it is ently homologous to the gonangulum irrespective of speculative at this stage, we entertain the possibility the fact that this terminus is restricted to the females that these sclerites could be homologous to a sclerite only. of the female which is regarded as the gonangulum of Second: In the course of the description of A. hor- the female genitalia (Bitsch 1974a; Klass et al. 2012). staspoecki our previous hypothesis (U. Asp ck 2002) of Since our concept of the homology of the male genital the composite nature of the hypovalva of certain Raphi- sclerites in Raphidioptera (and Neuropterida, as well) is diidae was corroborated: namely that the hypovalva based on the female terminalia of Archaeognatha (U. basally represents the gonapophyses 9 but terminally Asp ck & H. Asp ck 2008), a “male gonangulum hy- comprises the attached, or amalgamated parameres pothesis” should at least have a chance to be falsified. (¼ the complex of fused gonocoxites, gonostyli, gona- In Bitsch’s (1974a) description of the abdomen of a pophyses 10). In A. horstaspoecki this became obvious, female machilid, segment 9 (Fig. 1B) is characterized since the parameres appear distinctly as hooked scler- by an entirely membranous sternal area, and by the ites mounted to the gonapophyses 9. In most of the large gonocoxites 9, as well as gonapophyses 9. The other Alena species the parameres are camouflaged as gonocoxites 9 are surrounded by three pairs of sclerites: simple apices of the hypovalva. A. michoacana sp. n. in 1) a transverse bridge which is interpreted as the union a way represents a transitional mode between distinct of 2 sclerites detached from the anterior part of the and amalgamated (i.e., hidden) parameres. In several coxites, 2) a small sclerite at the lateroanterior part of Palaearctic species with similarly camouflaged para- the gonocoxites 9 addressed as the laterocoxite or go- meres, they must have evolved independently since nangulum, and 3) a precoxal sclerite. many Palaearctic species have clearly separated para- In Klass’s et al. (2012) interpretation of Bitsch meres which, of course, did not emerge secondarily (1974a), the “precoxites “ were handled as antelatero- from an amalgamation with the hypovalva. coxae, and the “laterocoxites” as postlaterocoxae. Ante- and postlaterocoxa together form the laterocoxa which represents the gonangulum.
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Phylogenetic and biogeographical Acknowledgements implications We are very much indebted to Norman Penny (San Francisco) for providing the male of A. michoacana sp. n., and to John Oswald (Col- The sister group relationship of the Nearctic Alena with lege Station) for providing the two female Alena specimens. Sincere the huge Palaearctic clade (and not with the Nearctic thanks to Harald Bruckner for graphical assistance, for the photo- Agulla) – resulting from the molecular analysis – is graph of the holotype and especially for providing the distribution not conflicting at all systematically. There is, however, a map. We thank John Plant (Vienna) for linguistic improvement. biogeographical dilemma, since Alena is restricted to the southernmost parts of North America, predominantly Mexico, whereas Agulla is restricted to the western parts References of North America, and only reaches the northern parts of Mexico. Altogether ten species of the genus Alena are Asp ck, H. 1998. Distribution and biogeography of the order Raphi- known now (see above under Alena). Eight of these spe- dioptera: updated facts and a new hypothesis. – In S. Panelius cies have so far only been recorded from certain small (ed.) Neuropterology 1997: Proceedings of the Sixth International areas in Mexico (see distribution map, Fig. 6), only A. Symposium on Neuropterology, Helsinki, Finland, 13–16 July distincta and A. minuta have also been found in the 1997. – Acta Zoologica Fennica 209: 33–44. Asp ck, H. 2002. The biology of Raphidioptera: A review of present southwestern most parts of the USA. Aside from the re- knowledge. – In G. Szir ki: Neuropterology 2000. Proceedings of cord of A. michoacana sp. n., the map also shows the two the Seventh International Symposium on Neuropterology, 6–9 new records of two additional species: Alena (Aztekora- August 2000, Budapest, Hungary. – Acta Zoologica Academiae phidia) caudata, 1 male: “Guerrero/6 miles east of/Xo- Scientiarum Hungaricae 48 (2): 35–50. chipala/July 13, 1985/Jones, Schaffner//TAMU – ENTO/ Asp ck, H. & Asp ck, U. 2007. The Raphidioptera of the Apennines X0066977/Alena/(Aztecoraphidia)/ caudata/Det. J. D. Peninsula: a biogeographical analysis. In Pantaleoni, R.A., Letar- Oswald 200400 [17 480 N99 340 W], and Alena (Aztekor- di, A. & Corazza, C. (eds): Proceedings of the Ninth International Symposium on Neuropterology, Ferrara, Italy, 20–23 June 2005. aphidia) australis, 1 male : “MEX: Baja Cal. Sur/8.4 mi. Annali del Museo Civico di Storia Naturale di Ferrara 8: 95–106. W. on Ramal/a Los Naranjos IX-13-88: E.G.Riley// Asp ck, H., Asp ck, U. & Rausch, H. 1991. Die Raphidiopteren der TAMU – ENTO/ X0073090//Alena/(Aztecoraphidia)/ Erde. Eine monographische Darstellung der Systematik, Taxono- australis/Det. J. D. Oswald 200400[18 210 N, 96 100 W], mie, Biologie, kologie und Chorologie der rezenten Raphidiop- both specimens are housed in collections at the Texas teren der Erde, mit einer zusammenfassenden bersicht der fossi- A & M University, College Station, and were kindly pro- len Raphidiopteren (Insecta: Neuropteroidea). Goecke & Evers, vided by Dr. John Oswald. Krefeld: 730 pp. and 550 pp. Asp ck, H., H lzel, H. & Asp ck, U. 2001. Kommentierter Katalog Moreover, the distribution map shows the few re- der Neuropterida (Insecta: Raphidioptera, Megaloptera, Neurop- cords of Alena based on female specimens which can- tera) der Westpal arktis. – Denisia 02: 606 pp. þ 6 Abb. not be identified at present. Asp ck, U. 2002. Male Genital Sclerites of Neuropterida: an Attempt How can the biogeographical pattern of Alena (U. As- at Homologisation (Insecta: Holometabola). – Zoologischer An- p ck et al. 2012) be explained? It can be surmised that a zeiger 241: 161–171. much more ancestral stem species of Alena reached Asp ck, U. & Asp ck, H. 1996. Raphidioptera. In Bousquets, J. E. L., Mexico when it was orographically much more homoge- Aldrete, A. N. G., Soriano, E. G. (eds): Biodiversidad, Taxonom a y Biogeograf a de Artrop dos de M xico: Hacia una s ntesis de neous than present. Tremendous radiation caused by vol- su conocimiento 19: D. R. Universidad Nacional Aut noma de canism, as well as multiple tectonic events, raising of M xico: pp. 277–286. mountains, flooding and climatic changes would have Asp ck, U. & Asp ck, H. 2008. Phylogenetic relevance of the genital had great impact on the rate of evolution of Alena. sclerites of Neuropterida (Insecta: Holometabola). – Systematic Nowadays, Alena in Mexico reflects a snakefly fauna im- Entomology 33: 97–127. prisoned in its former glacial refuge areas. Asp ck, U., Asp ck, H. & Rausch, H. 1994. Neue Arten der Familie Together with A. caudata, A. infundibulata, and A. Raphidiidae aus Mexiko und Nachweis einer Spermatophore in der Ordnung Raphidioptera (Insecta: Neuropteroidea). – Entomo- schremmeri, A. michoacana sp. n. mark the southern- logia Generalis 18: 145–163. most record of the family world-wide. These species Asp ck, U. & Contreras-Ramos, A. 2004. Alena (Aztekoraphidia) hor- occur between 15 and 20 northern latitude, while the staspoecki nov. spec. – a new snakefly from Mexico (Raphidiop- southernmost records of Raphidiidae in Africa are tera, Raphidiidae). In Asp ck, U. (ed.): Entomologie und Parasito- around 30 NL (Morocco) and in Asia around 23 NL logie. Festschrift zum 65. Geburtstag von Horst Asp ck. – (Taiwan). Denisia 13: 129–134. Finally: The Alena species differ from the other Ra- Asp ck, U., Haring, E. & Asp ck, H. 2012. Biogeographical implica- tions of a molecular phylogeny of the Raphidiidae (Raphidiop- phidiidae by remarkable biological characteristics. Their tera). – Mitteilungen der Deutschen Gesellschaft f r allgemeine larvae pupate in summer and autumn (and not, as in und angewandte Entomologie 18: 575–582. most Raphidiidae in spring after hibernation of the last Bitsch, J. 1974a. Morphologie abdominale des Machilides (Thysa- larval stage) and develop to imagoes within about two nura) – II. Squelette et musculature des segments g nitaux fe- weeks (Type III in H. Asp ck 2002). melles. – International Journal of Insect Morphology and Embry- ology 3: 101–120. Bitsch, J. 1974b. Morphologie abdominale des Machilides (Thysa- nura) – III. Squelette et musculature des segments g nitaux m les
# 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim museum-dez.wiley-vch.de 58 Aspo¨ck,U.& Aspo¨ck,H.: Alena and A. michoacana sp. n. from Mexico (Raphidioptera)
et des segments postg nitaux. – International Journal of Insect Klass, K. D., Matushkina, N. A. & Kaidel, J. 2012. The gonangulum: Morphology and Embryology 3: 203–224. a reassessment of its morphology, homology, and phylogenetic Haring, E., Asp ck, H., Bartel, D. & Asp ck, U. 2011. Molecular significance. – Arthropod Structure & Development 41 (4): 373– phylogeny of the Raphidiidae (Raphidioptera). – Systematic Ento- 394. mology 36: 16–30.