ZOOSYSTEMATICA ROSSICA, 24(1): 31–41 25 JUNE 2015 Evolution and taxonomic significance of the copulatory apparatus in Ensifera (Orthoptera). Part 2: Male genitalia in Grylloidea Эволюция и таксономическое значение копулятивного аппарата у длинноусых прямокрылых (Orthoptera: Ensifera). Часть 2: Гениталии самца у Grylloidea A.V. GOROCHOV А.В. ГОРОХОВ A.V. Gorochov, Zoological Institute, Russian Academy of Sciences, 1 Universitetskaya Emb., St Petersburg 199034, Russia. E-mail: [email protected] In the superfamily Grylloidea, the main trends in the evolution of the copulatory apparatus were probably connected with the transformation of simple membranous (hagloid) genitalia, characteristic of ancient groups of Ensifera, into a complicated organ with highly specialized sclerites for fixation of the female during copulation. This evolutionary process was probably accompanied by partial reduction and disappearance of paraproctal hooks or other external abdominal processes which may have been used by these ancient groups for female fixation. Sclerites in the male genitalia of Grylloidea appeared independently not less than four times: in Gryllotalpidae, Myrmecophilidae, Gryllidae and Mogoplistidae. This hypothesis, proposed by Gorochov in 1984, was one of the reasons for division of the recent Grylloidea into four families. Each of the first three families acquired sclerites in the male genitalia once, whereas Mogoplistidae possibly acquired them more than once: male genitalia of the tribe Mogoplistini are of the hagloid type, membranous; in most genera of Arachnocephalini (Mogoplistinae), in Pseudomogoplistes (Mogoplistinae) and in Malgasiinae, male genitalia have three types of sclerites which could have also appeared independently. Moreover, many sclerites of the male genitalia in Grylloidea are formed independently and have significant convergent similarity; this is why the nomenclature of male genital structures based partly on their function and posi- tion but not exclusively on their homology is simpler and much more suitable for descriptions and morphological investigations. This nomenclature is considered here. В надсемействе Grylloidea главные тенденции в эволюции копулятивного аппарата были, очевидно, связаны с преобразованием простых мембранозных (хаглоидных) гениталий, характерных для древних групп Ensifera, в усложненный орган с высокоспециализиро- ванными склеритами для фиксации самки при копуляции. Возможно, этот эволюцион- ный процесс сопровождался частичной редукцией и исчезновением парапроктальных крючков или других наружных выростов брюшка, которые могли использоваться этими древними группами для фиксации самки. Cклериты в гениталиях самца Grylloidea воз- никают независимо не менее четырех раз: у Gryllotalpidae, Myrmecophilidae, Gryllidae и Mogoplistidae. Эта гипотеза, предложенная Гороховым в 1984 г., была одной из причин для деления современных Grylloidea на четыре семейства. Каждое из трех первых семейств приобрело склериты в гениталиях самца однажды, но Mogoplistidae, возможно, приоб- ретали их неоднократно: гениталии самца в трибе Mogoplistini – хаглоидного типа, мем- бранозные; у большинства родов Arachnocephalini (Mogoplistinae), у Pseudomogoplistes (Mogoplistinae) и у Malgasiinae гениталии самца имеют три типа склеритов, которые могли возникнуть также независимо. Более того, многие склериты гениталий самца у Grylloidea формируются независимо и имеют значительное конвергентное сходство; вот © 2015 Zoological Institute, Russian Academy of Scienсes 32 A.V. GOROCHOV. COPULATORY APPARATUS IN ENSIFERA (ORTHOPTERA). 2 почему номенклатура генитальных структур самца, частично основанная на их функции и положении, но не только на их гомологии, является более простой и более пригодной для описаний и морфологических исследований. Здесь эта номенклатура рассмотрена. Key words: copulatory apparatus, evolution, morphology, taxonomic importance, Orthoptera, Ensifera, Grylloidea Ключевые слова: копулятивный аппарат, эволюция, морфология, таксономическое зна- чение, Orthoptera, Ensifera, Grylloidea INTRODUCTION was proposed by Gorochov (1984, 1986). It was based on characters of the copulatory This series of papers is the next step in apparatus as well as of some other organs. the development of hypotheses on the ensif- In these works, the terminology of copula- eran evolution published in a special mono- tory structures proposed by the previous graph on this subject (Gorochov, 1995a, b). authors (Randell, 1964; Alexander & Otte, In the previous communication of this se- 1967; Chopard, 1969) was used with some ries, some general problems of evolution of original modifications. This terminology the copulatory apparatus in Ensifera were took into account the evidence that many discussed (Gorochov, 2014). These prob- sclerites of the phallus (= male genitalia) lems concerned primary and secondary sex- were formed independently in different ual characters, intraspecific stability of these groups of Grylloidea and have significant characters, interspecific sexual differences, convergent similarity (convergent origin of the “lock-and-key” and “genital clock” hy- many structures in the male genitalia was potheses, early evolution of sexual char- also observed in Dictyoptera; Anisyutkin, acters in orthopteroid insects, and general 2009, 2011). Therefore, this terminology trends in the evolution of the ensiferan cop- was partly based on the function and posi- ulatory apparatus. The present communica- tion of genital structures but not solely on tion continues this series and contains the their homology. Such terminology is rather discussion of the structure of male genitalia simple and most suitable for descriptions in the superfamily Grylloidea and analysis of and morphological investigations. the main trends in their evolution. A short time later, a new phylogenetic The paper is based on the data present- scheme of the Grylloidea and a new nomen- ed by the author at the 11th International clature of its phallus were proposed in some Congress of Orthopterology (11th–15th of the first publications by Desutter (1987, August 2013, Kunming, China) and briefly 1988). Her opinion was based solely on the outlined in the abstract of that presentation study of the phallus; therefore she could not (Gorochov, 2013). discover the numerous cases of convergence in male genital structures. The nomencla- RESULTS ture of Desutter suggested that any single Phylogenetic investigations term should refer only to homologous (not of the Grylloidea and nomenclature convergent) structures, so that a great of its male genitalia number of terms would need to create for all structures of convergent origin. These cases The study of morphological evolution of convergence were not taken into account is closely connected with the phylogenetic in her phylogenetic scheme of Grylloidea: study of the group in question. In the su- the principal division of Gryllidae into perfamily Grylloidea, the first phyloge- “Diplosclerophalles” (Oecanthinae and netic scheme of families and subfamilies part of Phalangopsinae) and “Monosclero- © 2015 Zoological Institute, Russian Academy of Scienсes, Zoosystematica Rossica 24(1): 31–41 A.V. GOROCHOV. COPULATORY APPARATUS IN ENSIFERA (ORTHOPTERA). 2 33 phalles” (all the other subfamilies of Gryl- membranous (hagloid) phallus, charac- lidae except Pteroplistinae), separation of teristic of ancient groups of Ensifera and the phalangopsid tribe Paragryllini from preserved in many recent representatives all the other taxa of “Monosclerophalles”, of the infraorder Tettigoniidea (Hagloidea, and unification of Mogoplistidae with Myr- Stenopelmatoidea and Tettigonioidea), into mecophilidae in a holophyletic clade were a complicated organ with highly specialized unsuccessful and later rejected by Desut- sclerites for fixation of female during copu- ter-Grandcolas (1992) or not supported by lation. This evolutionary process was prob- later morphological (Gorochov, 1995) and ably accompanied by partial reduction and molecular (Jost & Shaw, 2006) studies. In disappearance of hooks or other external her subsequent publications, no new phylo- processes of the male abdomen which could genetic scheme of Grylloidea was proposed. be used by these ancient groups for female An additional nomenclature for struc- fixation (preservation of the tendency to tures of the cricket phallus was also pro- form the latter copulatory structures can be posed by Mesa et al. (1997, 1999a, b, c). This observed in many other groups of Orthop- nomenclature had no phylogenetic explana- tera). Sclerites in the phallus of Grylloidea tion: it seems that these authors used their independently appeared not less than 4 terms for homologous structures, but their times: in Gryllotalpidae, Myrmecophilidae homologizations were often erroneous [for (including Bothriophylacinae), Gryllidae example, their terms “PECS” and “DECS” and Mogoplistidae. This hypothesis (Goro- were used in Nemobiinae for epiphallus and chov, 1984) was one of the reasons for divi- rami, respectively (Mesa et al., 1999c: Figs sion of the recent Grylloidea into four fami- 8–15); but in Gryllinae, these terms were lies (Fig. I). Each of the first three families used in the opposite sense: “PECS” for rami, acquired sclerites in the phallus once, but and “DECS” for epiphallus (Mesa & Garcia, Mogoplistidae possibly acquired them more 1999a: figs 4–11 and 20–27)]. than once. The first phylogenetic scheme and ear- There were two main ways of emergence lier terminology of genital structures were of sclerites in the