NATALIA VON ELLENRIEDER Natural History Museum of Los Angeles County A SYNOPSIS OF THE NEOTROPICAL SPECIES OF ‘AESHNA’ FABRICIUS: THE GENUS RHIONAESCHNA FÖRSTER (ODONATA: AESHNIDAE) von Ellenrieder, N., 2003. A synopsis of the Neotropical species of ‘Aeshna’ Fabricius: The Genus Rhionaeschna Förster (Odonata: Aeshnidae). – Tijdschrift voor Entomologie 146: 67- 207, figs. 1-468, tabs. 1-3. [ISSN 0040-7496]. Published 1 June 2003. This study includes a revisionary, phylogenetic and biogeographical analysis of Neotropical com- ponents of Aeshna Fabricius characterized by a midventral tubercle on abdominal sternum I. Phylogenetic relationships of the Neotropical species of Aeshna were inferred based on 39 adult characters. Ingroup taxa included 68 out of the 85 species currently assigned to Aeshna, and two species each of Andaeshna De Marmels and Anaciaeschna Selys. Oreaeschna dictatrix Lieftinck was chosen as outgroup. The strict consensus tree obtained after successive weighting revealed that Aeshna is not monophyletic; some of its species are more closely related to Anaciaeschna or Andaeschna. The name Aeshna should consequently be restricted to the Holarctic group includ- ing the type species Aeshna grandis Fabricius. In the present synopsis the generic name Rhion- aeschna Förster is assigned to the New World group characterized by the presence of a conical tu- bercle on abdominal sternum I, comprising 39 species formerly assigned to Aeshna. The synopsis includes keys to adults of both sexes, diagnoses, biological notes, distribution maps and more than 400 diagnostic illustrations. Rhionaeschna demarmelsi sp. n. is described, R. maita Förster is considered a junior synonym of R. brevifrons (Hagen), R. peralta (Ris) is considered a valid species, not a synonym of R. variegata (Fabricius), R. planaltica (Calvert) is raised to specific rank, ‘Aeshna’ williamsoniana Calvert, formerly included in the subgenus Hesperaeschna Cock- erell, is excluded from Rhionaeschna, and lectotypes are designated for R. maita, R. intricata (Martin), R. multicolor (Hagen), R. bonariensis (Rambur), R. diffinis (Rambur), and R. peralta. Females of three species and larvae of 16 species are still unknown. Rhionaeschna occurs from southern Argentina to southern Canada, but is primarily Neotropical with its highest diversity along the Andean mountain range between Venezuela and Bolivia. It is absent from the Amazon basin, only three species occur north to the Neotropical region. The sister group of Rhionaeschna includes some African species of ‘Aeshna’ (A. rileyi Calvert, A. subpupillata McLachlan and A. moori Pinhey). Rhionaeschna plus the African clade constitute the sister group of Andaeshna, Anaciaeschna, Anax Leach, Hemianax Selys and several species of ‘Aeshna’ of uncertain affinities (i.e. A. affinis Vander Linden, A. brevistyla Rambur, A. ellioti Kirby, A. mixta Latreille, A. isoceles Müller and A. williamsoniana); the phylogenetic relationships within this complex are not yet known and their resolution is beyond the scope of this study. Rhionaeschna is absent from the Brazilian shield. Its related species and genera (‘A.’ rileyi, ‘A.’ subpupillata, ‘A.’ moori in Africa; ‘A.’ brevistyla in Australia and New Zealand, Andaeshna in the Andes and ‘A.’ williamsoniana in Central America, ‘A.’ isoceles and highest species numbers of Anaciaeschna, Hemianax and Anax species in the Indo-Australian region) display a low diversity in Africa, which suggests a trans-Pa- cific rather than trans-Atlantic (Gondwanian) track, as has been hypothesized for other groups of similarly distributed odonates. Dr. N. von Ellenrieder, Natural History Museum of Los Angeles County, 900 Exposition Boulevard, CA 90007, U.S.A. E-mail: [email protected] Key words. – Odonata; Aeshnidae; Aeshna; Rhionaeschna; systematics; keys; cladistics; phyloge- ny; biogeography. CONTENTS Taxonomic analysis...............................................70 Introduction .........................................................68 Taxonomic part Material and methods Rhionaeschna Förster .............................................72 Phylogenetic analysis.............................................69 Keys Biogeographic analysis...........................................70 Keys to males of Rhionaeschna...............................73 67 Downloaded from Brill.com10/08/2021 11:25:36PM via free access T E, 146, 2003 Keys to females of Rhionaeschna ............................77 INTRODUCTION Rhionaeschna species accounts 1. R. draco group...................................................80 The genus Aeshna was described by Fabricius in Rhionaeschna draco (Rácenis).................................80 1775 to include four species: A. forcipata Linnaeus, A. 2. Marmaraeschna group .......................................81 grandis Linnaeus, A. variegata Fabricius and A. clavata Rhionaeschna brevicercia (Muzón & von Ellenrieder). Fabricius. Selys (1883) fixed A. juncea as the type .......................................................................81 species of Aeshna, but as this species was not included Rhionaeschna brevifrons (Hagen)............................82 in the original description of the genus, its designation Rhionaeschna fissifrons (Muzón & von Ellenrieder) 83 is invalid according to the ICZN (1999). Latreille Rhionaeschna intricata (Martin).............................84 (1810) mentioned A. forcipata as the type species of Rhionaeschna obscura (Muzón & von Ellenrieder) .84 Aeshna, but Aeshna forcipata of Latreille is a synonym Rhionaeschna pallipes (Fraser) ................................85 of Libellula vulgatissimus and not the same species as Rhionaeschna vigintipunctata (Ris) .........................86 A. forcipata Linnaeus, and thus it is also ineligible as 3. Schizuraeschna group.........................................86 the type species of Aeshna. Therefore, the first valid Rhionaeschna dugesi (Calvert) ................................86 type designation is that of Cowley (1934), who desig- Rhionaeschna jalapensis (Williamson).....................87 nated Aeshna grandis as type species of Aeshna. Rhionaeschna multicolor (Hagen) ...........................88 Aeshna was the first described genus of Aeshnidae, Rhionaeschna mutata (Hagen)................................89 and the current number of genera within this family 4. Neureclipa group ...............................................89 now stands at 50. Nineteen genera (40% of the total Rhionaeschna absoluta (Calvert) .............................89 number of currently accepted genera) have been creat- Rhionaeschna bonariensis (Rambur)........................90 ed to include species originally described as Aeshna as Rhionaeschna diffinis (Rambur)..............................91 follows: Amphiaeschna Selys, 1871, Anaciaeschna Rhionaeschna elsia (Calvert) ...................................92 Selys, 1878, Andaeshna De Marmels, 1994, Basi- Rhionaeschna galapagoensis (Currie) .......................93 aeschna Selys, 1883, Boyeria McLachlan, 1896, Cali- 5. R. variegata group .............................................94 aeschna Selys, 1883, Castoraeschna Calvert, 1952, Rhionaeschna brasiliensis (von Ellenrieder & Martins Coryphaeschna Williamson, 1903, Epiaeschna Hagen, Costa).............................................................94 1877, Gomphaeschna Selys, 1871, Gynacantha Ram- Rhionaeschna californica (Calvert)..........................94 bur, 1842, Hemianax Selys, 1883, Nasiaeschna Selys Rhionaeschna confusa (Rambur) .............................95 in Förster, 1900, Neuraeschna Hagen, 1867, Oplon- Rhionaeschna marchali (Rambur)...........................96 aeschna Selys, 1883, Planaeschna McLachlan, 1896, Rhionaeschna peralta (Ris)......................................97 Polycanthagyna Fraser, 1933, Remartinia Navás, 1911, Rhionaeschna tinti (von Ellenrieder).......................99 and Staurophlebia Brauer, 1865. No unique characters Rhionaeschna variegata (Fabricius) .........................99 define ‘Aeshna’, its species being usually identified as 6. R. cornigera group ...........................................101 those not belonging to other genera. Peters (1987) an- Rhionaeschna cornigera (Brauer)...........................101 alyzed the European genera of Aeshnidae and con- Rhionaeschna haarupi (Ris) ..................................102 cluded that Aeshna was not monophyletic, with ‘Aesh- Rhionaeschna manni (Williamson & Williamson)103 na’ affinis van der Linden, 1820 and A. mixta Latreille, Rhionaeschna nubigena (De Marmels)..................103 1805 more closely related to Anaciaeschna and Anax Rhionaeschna pauloi (Machado)...........................104 than to the remaining European Aeshna species. Rhionaeschna planaltica (Calvert).........................104 The most recent treatment of the Neotropical Rhionaeschna psilus (Calvert) ...............................106 species of ‘Aeshna’ was by Calvert (1956). His study Rhionaeschna vazquezae (Gonzalez) .....................106 comprised species currently assigned to Andaeshna, Re- 7. R. punctata group............................................107 martinia, Castoraeschna and Coryphaeschna. Calvert Rhionaeschna biliosa (Kennedy ) ..........................107 (1956) included detailed redescriptions of all species Rhionaeschna condor (De Marmels) .....................108 but no diagnoses were provided outside the keys. The Rhionaeschna decessus (Calvert) ............................108 keys were based almost exclusively on thoracic color Rhionaeschna