Phylogeny of the Family Sialidae (Insecta: Megaloptera) Inferred from Morphological Data, with Implications for Generic Classiﬁcation and Historical Biogeography

Home , Alderfly, Megaloptera, Sialis, Sialis lutaria

Cladistics

Cladistics (2014) 1–32 10.1111/cla.12071

Phylogeny of the family Sialidae (Insecta: Megaloptera) inferred from morphological data, with implications for generic classiﬁcation and historical biogeography

Xingyue Liua,*, Fumio Hayashib and Ding Yanga,*

aDepartment of Entomology, China Agricultural University, Beijing, 100193, China; bDepartment of Biology, Tokyo Metropolitan University, Minamiosawa 1–1, Hachioji, Tokyo, 192–0397, Japan Accepted 6 January 2014

Abstract

Sialidae (alderflies) is a family of the holometabolous insect order Megaloptera, with ca. 75 extant species in eight genera distributed worldwide. Alderflies are a group of “living fossils” with a long evolutionary history. The oldest fossil attributed to Sialidae dates back to the Early Jurassic period. Further, the global distribution of modern-day species shows a remarkably dis- junctive pattern. However, due to the rareness of most species and scarcity of comprehensive taxonomic revisions, the phylogeny of Sialidae remains largely unexplored, and the present classification system is in great need of renewal. Here we reconstruct the first phylogeny for Sialidae worldwide based on the most comprehensive sampling and broadest morphological data ever presented for this group of insects. All Cenozoic alderflies belong to a monophyletic clade, which may also include the Early Juras- sic genus †Dobbertinia, and the Late Jurassic genus †Sharasialis is their putative sister taxon. Two subfamilies of Sialidae are proposed, namely †Sharasialinae subfam. nov. and Sialidinae. Austrosialis is the sister of all other extant genera, an assemblage which comprises three monophyletic lineages: the Stenosialis lineage, the Ilyobius lineage, and the Sialis lineage. The revised classification of Sialidae is composed of 12 valid genera and 87 valid species. Ilyobius and Protosialis are recognized as valid generic names, while Nipponosialis is treated as a synonym of Sialis. Reconstruction of the ancestral area proposes a global distribution of alderflies in Pangaea before their diversification. The generic diversification of alderflies might have occurred before the breakup of Pangaea, but the divergence of some lineages or genera was probably promoted by the splitting of this supercontinent. © The Willi Hennig Society 2014.

Introduction of nygmata on wings, and the loss of callus cerci, while their larvae are distinguished by the presence of The family Sialidae, commonly called alderflies, is a terminal filament on the tenth abdominal segment. group of little-known insects belonging to Megalopter- More obviously, in general appearance, the adult sia- a, which is a holometabolous insect order placed in lids are much smaller than corydalids and have the superorder Neuropterida and contains only two uniformly dark wings (Fig. 1). The alderfly larvae are extant families: Corydalidae and Sialidae. Compared predaceous, exclusively aquatic, and inhabit streams, with Corydalidae, the adults of Sialidae are character- rivers, or lakes where the substrate is soft and detritus ized by the absence of ocelli, the pronotum shorter is abundant (Flint et al., 2008). Adult alderflies gener- than wide, the dilated fourth tarsomeres, the absence ally do not feed, although some species have been observed to visit flowers (Kaiser, 1961; Azam and Anderson, 1969). Further, they are poor fliers, and *Corresponding author: E-mail address: [email protected] and [email protected] remain in the same general area where the larvae

(a) (b) (c)

(d) (e) (f)

(g) (h) (i) Fig. 1. Habitus of alderfly adults, male: (a) Austrosialis ignicollis; (b) Stenosialis australiensis; (c) Leptosialis africana; (d) Haplosialis afra; (e) Indosialis bannaensis; (f) Ilyobius mexicana; (g) Protosialis americana; (h) Sialis jezoensis; (i) Sialis annae. Scale bar = 5.0 mm. occurred (Flint et al., 2008). In contrast to corydalids, 1920 from the Lower Jurassic of Germany, which was sialid adults are mostly diurnal and seldom captured originally placed in Mecoptera (Handlirsch, 1920) and by light (New and Theischinger, 1993). Although some was transferred to Sialidae by Ansorge (2001). The alderfly species from Palaearctic and Nearctic realms second Mesozoic alderfly †Sharasialis fusiformis are readily found in the field, most species from other Ponomarenko, 2012 was discovered very recently by zoogeographical realms are extremely rare in collec- Ponomarenko (2012); it is a larval fossil from the tions. Upper Jurassic of Mongolia. All other alderfly fossils Some European alderfly species were described very occur from the Cenozoic. They include 10 species early, and aspects of their morphology, physiology, placed in six genera (Lambkin, 1992; Nel et al., 2002; and ecology have been extensively studied. The first Wichard and Engel, 2006; Engel and Grimaldi, 2007). described species, Sialis lutaria (Linnaeus, 1758), was Currently, extant Sialidae contain eight valid genera originally placed in the brown lacewing genus Hemero- and ca. 75 valid species, while fossil Sialidae encom- bius (Geigy and DuBois, 1935; Selman, 1960; Elliott, pass seven valid genera (including five extant genera) 1996). Latreille (1802) erected the genus Sialis, which and a total of 12 valid species (Yang and Liu, 2010; is the first valid generic taxon in Sialidae and included Oswald, 2012). almost all alderfly species described in the 19th cen- The Sialidae occur in all continents of the world tury. Previously, Sialidae was defined in a broader (except Antarctica), and their geographical distribution sense, and included Corydalidae and Sialidae until is interesting in that the modern fauna differs greatly Davis (1903) divided the “Sialididae” into two subfam- at the genus and species level among main zoogeo- ilies: Sialidinae and Corydalinae. Both subfamilies graphical realms. Five extant genera are presently dis- were raised to full familial status by Tillyard (1919). tributed in the Southern Hemisphere, namely Most genera and nearly a half of all extant species of Austrosialis Tillyard, 1919 and Stenosialis Tillyard, Sialidae were described in the first half of the 20th cen- 1919; which are endemic to Australia, Protosialis van tury. Since then, the generic classification system has der Weele, 1909; currently endemic to Neotropics but hardly changed (van der Weele, 1910; Tillyard, 1919; also found in the Eocene Baltic amber, Leptosialis Esben-Petersen, 1920; Lestage, 1927; Barnard, 1931; Esben-Petersen, 1920; endemic to South Africa, and Ross, 1937). Several additional regional revisionary Haplosialis Navas, 1936, endemic to Madagascar. works on Sialidae were published from 1950 to 2010s Altogether they contain 18 species, ca. 20% of the and described ca. 40 new species, e.g. Kuwayama world’s species. The remaining species are distributed (1962), Flint (1964), Aspock€ et al. (1980, 2001a), in the Northern Hemisphere, with ca. 50 species placed Vshivkova (1985), Whiting (1991), Hayashi and Suda in the dominant genus Sialis, which is widespread in (1995), Theischinger (2000), Liu and Yang (2006a,b), Eurasia and North America, and a few species placed Liu et al. (2008), Contreras-Ramos (2008), and Price in Nipponosialis Kuwayama, 1962 (ranging mainly in et al. (2012). Considering the extinct Sialidae, the earli- Taiwan, Ryukyus, and Japan) and Indosialis Lestage, est definite fossil is †Dobbertinia reticulata Handlirsch, 1927 (endemic to Oriental realm). Fossil alderflies were X. Liu et al. / Cladistics (2014) 1–32 3 found mainly in the Northern Hemisphere and most of Sialidae is discussed in light of the proposed of them are restricted to Europe (Engel and Grimaldi, phylogenetic hypothesis and fossil evidence. 2007), while an unnamed species of Austrosialis is recorded from the Palaeocene of Australia (Lambkin, 1992). Materials and methods Interpreting historical biogeography of the group requires appropriate phylogenetic data. The nature of Specimens examined and terminology the sister-group to Sialidae has been debated. The sister relationship between Sialidae and Raphidioptera We aimed to include all valid species of both fossil was supported by the basal fusion of MP and CuA and extant Sialidae as the ingroup taxa in the present veins in the forewing by Hennig (1953), the female phylogenetic analysis. However, a few species subse- telotrophic ovarioles by Stys and Bilinski (1990), and quently were excluded from the primary taxa list. the molecular evidence presented by Winterton et al. First, a fossil species, Sialis strausi Illies, 1967 was (2010), which indicates a paraphyletic Megaloptera. excluded because it is known only based on a poorly Alternatively, Sialidae was considered to be the sister preserved larva, without any informative characters of the corydalid subfamily Chauliodinae within a for the analysis. Second, Protosialis brasiliensis monophyletic Megaloptera based on a greater reduc- Navas, 1936, Sialis vanderweelei Aspock€ & Aspock,€ tion or fusion of genital structures according to Con- 1983, Sialis dorochovae Vshivkova, 1985, and Sialis treras-Ramos (2004). Contrary to this, the sister gonzalezi Vshivkova, 1985 were also excluded because relationship between Sialidae and Corydalidae was they are considered as invalid species in the present recovered in both morphological and molecular data study (see updated world catalog of Sialidae in Table (Aspock€ et al., 2001b; Beutel and Friedrich, 2008). S4). Finally, a total of 86 species of Sialidae were More recently a mitochondrial phylogenomic study included in the phylogenetic analysis (see detailed confirmed the traditional higher classification of Mega- taxa list in Table 1). A fishfly species, Platychauliodes loptera, i.e. Sialidae + (Chauliodinae + Corydalinae) capensis Barnard, 1931 (Megaloptera: Corydalidae: (Wang et al., 2012). Chauliodinae) and a snakefly species, Sininocellia gi- The internal phylogeny of Sialidae is too poorly gantos Yang, 1985 (Raphidioptera: Inocelliidae) were known to conclusively address the question of their selected as the outgroup in the analysis. The out- origin and diversification. Thus far, only two pub- group selection was based on the hypothesis that lished works, Whiting (1994) and Nel et al. (2002), Corydalidae is the sister of Sialidae and that Raphid- have focused on the intergeneric and interspecific phy- ioptera is the sister of Megaloptera + Neuroptera logeny of the Sialidae. Whiting (1994) performed the (Aspock€ et al., 2001b; Wang et al., 2012). Both two first cladistic analysis on Sialidae based on morpholog- outgroup species are relatively basal and have many ical data to unravel the interspecific phylogeny of comparable plesiomorphic characters (Liu et al., North American Sialis. Nel et al. (2002) attempted to 2011, 2012a). reconstruct the intergeneric phylogeny of Sialidae, The specimens of extant Sialidae examined for the including both extant and fossil genera based on only analysis are deposited in the Albany Museum, Gra- wing venation characters, but failed to obtain well hamstown, South Africa (AMGS); the Australian resolved results. Therefore, due to the poorly studied Museum, Sydney, Australia (AMS); the Entomological intergeneric and interspecific relationships of the Siali- Museum, China Agricultural University, Beijing, dae, the generic classification remains obscure and China (CAU); the Deutsches Entomologisches Institut, severely in need of revision, a fact that has been Muncheberg,€ Germany (SDEI); the Fumio Hayashi repeatedly lamented by numerous authors (New and personal collection in Tokyo Metropolitan University, Theischinger, 1993; Penny, 1993; Whiting, 1994; Con- Tokyo, Japan (HFC); the Royal Belgian Institute of treras-Ramos, 2008; Liu et al., 2008; Price et al., Natural Sciences, Brussels, Belgium (IRSB); the Hun- 2012). garian Natural History Museum, Budapest, Hungary Our goal was to revise the classification system and (HNHM); the Illinois Natural History Survey, Cham- to clarify the evolutionary pattern of Sialidae. For this paign, Illinois, USA (INHS); the Museum fur€ Naturk- purpose, we examined large numbers of specimens unde, Berlin, Germany (MFN); the Museum National from almost all alderfly species worldwide. Here we d’Histoire Naturelle, Paris, France (MNHN); the present a phylogenetic hypothesis for Sialidae based Musee Cantonal de Zoologie, Lausanne, Switzerland on the most comprehensive morphological data avail- (MZL); the Warsaw Museum of the Institute of Zool- able to date. Further, we aim to test the monophyly of ogy, Polish Academy of Sciences, Warsaw, Poland all described genera and to examine the intergeneric (MZPW); the Natural History Museum, London, UK relationships, as well as the interspecific relationships, (BMNH); the Naturhistorische Museum Wien, Vienna, for some speciose genera. The historical biogeography Austria (NHMW); the National Museum of Natural 4 X. Liu et al. / Cladistics (2014) 1–32

Table 1 Taxa included in the phylogenetic analysis

Genus Species Authors Distribution Guiding literature

Sininocellia gigantos Yang, 1985 OR: China Liu et al. (2012a) Platychauliodes capensis Barnard, 1931 AF: South Africa Liu et al. (2011) Austrosialis ignicollis Tillyard, 1918 AU: Australia Austrosialis maxmouldsi Theischinger, 1983 AU: Australia Haplosialis afra (Navas, 1936) AF: Madagascar Haplosialis madegassa (Navas, 1927) AF: Madagascar Navas (1927) Indosialis bannaensis Liu, Yang & Hayashi, 2006 OR: China, Laos, Thailand, Vietnam Indosialis minora (Banks, 1920) OR: Malaysia, Singapore Indosialis indicus Liu, Flint & Yang, 2008 OR: India Leptosialis africana Esben-Petersen, 1920 AF: South Africa Leptosialis necopinata Price, Liu, de Moor & Villet, 2012 AF: South Africa Nipponosialis jezoensis (Okamoto, 1910) PA: Japan, Russia Nipponosialis kuwayamai Hayashi & Suda, 1995 stat. nov. PA: Japan Nipponosialis kumejimae (Okamoto, 1910) OR: China, Japan Protosialis bifasciata (Hagen, 1861) NT: Cuba Protosialis bimaculata Banks, 1920 NT: Bolivia Banks (1920) Protosialis chilensis (McLachlan, 1870) NT: Chile Protosialis flammata Penny, 1981 NT: Brazil Protosialis flavicollis (Enderlein, 1910) NT: Colombia Protosialis hauseri Contreras-Ramos, Fiorentin & NT: Brazil Contreras-Ramos Urakami, 2005 et al. (2005) Protosialis mexicana (Banks, 1901) NT: Mexico, Panama Protosialis nubila Navas, 1933 NT: Brazil Protosialis ranchograndis Contreras-Ramos, 2006 NT: Venezuela Contreras-Ramos (2006) Sialis abchasica Vshivkova, 1985 PA: Georgia, Russia Vshivkova (1985) Sialis aequalis Banks, 1920 NA: USA Sialis americana (Rambur, 1842) NA: USA Sialis annae Vshivkova, 1979 PA: Russia Sialis arvalis Ross, 1937 NA: USA Sialis bifida Hayashi & Suda, 1997 PA: Japan Sialis bilobata Whiting, 1991 NA: USA Whiting (1991) Sialis californica Banks, 1920 NA: Canada, USA Sialis concava Banks, 1897 NA: Canada, USA Sialis contigua Flint, 1964 NA: USA Sialis cornuta Ross, 1937 NA: Canada, USA Sialis driesbachi Flint, 1964 NA: USA Sialis elegans Liu & Yang, 2006 OR: China Sialis fuliginosa Pictet, 1836 PA: Europe Sialis glabella Ross, 1937 NA: USA Sialis hamata Ross, 1937 NA: Canada, USA Sialis hasta Ross, 1937 NA: USA Sialis henanensis Liu & Yang, 2006 OR: China Sialis infumata Newman, 1938 NA: Canada, USA Sialis iola Ross, 1937 NA: Canada, USA Sialis itasca Ross, 1937 NA: Canada, USA Sialis japonica van der Weele, 1909 PA: Japan Sialis jianfengensis Yang, Yang & Hu, 2002 OR: China Sialis joppa Ross, 1937 NA: Canada, USA Sialis klingstedti Vshivkova, 1985 PA: Kazakhstan, Russia Vshivkova (1985) Sialis kunmingensis Liu & Yang, 2006 OR: China Sialis kyushuensis Hayashi & Suda, 1995 stat. nov. PA: Japan Sialis levanidovae Vshivkova, 1980 PA: Russia Sialis longidens Klingstedt, 1932 PA: China, Japan, Mongolia, Russia Sialis luohanbaensis Liu, Hayashi & Yang, 2012 OR: China Sialis lutaria (Linnaeus, 1758) OR: Europe Sialis martynovae Vshivkova, 1980 PA: Russia Sialis melania Nakahara, 1915 PA: Japan. Sialis mohri Ross, 1937 NA: Canada, USA. Sialis morio Klingstedt, 1932 PA: Europe Sialis navasi Liu, Hayashi & Yang, 2009 OR: China X. Liu et al. / Cladistics (2014) 1–32 5

Table 1 (Continued)

Genus Species Authors Distribution Guiding literature

Sialis nevadensis Davis, 1903 NA: USA Sialis nigripes Pictet, 1865 PA: Europe Sialis nina Townsend, 1939 NA: USA Sialis occidens Ross, 1937 NA: USA Sialis rotunda Banks, 1920 NA: Canada, USA Sialis sibirica McLachlan, 1872 PA: northern Europe and northeastern Asia Sialis sinensis Banks, 1940 OR: China, Japan Sialis sordida Klingstedt, 1932 PA: Europe and central Asia Sialis spangleri Flint, 1964 NA: USA Sialis tohokuensis Hayashi & Suda, 1995 stat. nov. PA: Japan Sialis toyamaensis Hayashi & Suda, 1995 stat. nov. PA: Japan Sialis vagans Ross, 1937 NA: Canada, USA Sialis velata Ross, 1937; NA: Canada, USA Sialis versicoloris Liu & Yang, 2006 OR: China Sialis yamatoensis Hayashi & Suda, 1995 PA: Japan Sialis zhiltzovae Vshivkova, 1985 PA: Georgia Vshivkova (1985) Stenosialis australiensis Tillyard, 1918 AU: Australia Stenosialis hollowayi Theischinger, 1983 AU: Australia †Dobbertinia reticulata Handlirsch, 1920 PA: Germany, Lower Jurassic Ansorge (2001) †Eosialis dorisi Nel et al., 2002 PA: Parisian amber, Lowermost Eocene †Indosialis beskonakensis Nel, 1988 PA: Turkey, Oligocene/Miocene Nel (1988) †Proindosialis cantalensis Nel, 1988 PA: France, Upper Miocene Nel (1988) †Protosialis baltica Wichard, 1997 PA: Baltic amber, Upper Eocene Wichard (1997) †Protosialis casca Engel & Grimaldi, 2007 NT: Dominican amber, Miocene Engel and Grimaldi (2007) †Protosialis herrlingi Wichard, 2002 PA: Baltic amber, Upper Eocene Wichard (2002) †Protosialis voigti Wichard & Engel, 2006 PA: Baltic amber, Middle Eocene Wichard and Engel (2006) †Sharasialis fusiformis Ponomarenko, 2012 PA: Mongolia: Upper Jurassic Ponomarenko (2012) †Sialis groehni Wichard, 1997 PA: Baltic amber, Upper Eocene Wichard (1997) †Sialis muratensis Nel, 1988 PA: France, Upper Miocene/Pliocene Nel (1988)

AF, Afrotropical; AU, Australian; NA, Nearctic; NT, Neotropical; OR, Oriental; PA, Palaearctic.

History, Smithsonian Institution, Washington, DC, characters of Sialidae, coding 35 characters. After USA (USNM); the National Museum of Nature and careful evaluation of these previously proposed charac- Science, Tokyo, Japan (NSMT); the Iziko South Afri- ters, we found that nearly half were of poor phyloge- can Museum, Cape Town, South Africa (SAMC); and netic utility, mostly due to ambiguous homology, such the Hokkaido University Museum, Sapporo, Japan as the coloration of head and thorax, the number of (SEHU). costal crossveins, etc. In the present study, we exam- Terminology of wing venation follows Wootton ined the specimens of most extant taxa included in the (1979). The homologization of genital sclerites among analysis, as well as the holotype of Eosialis dorisi Nel Neuropterida families was reviewed by Aspock€ and et al. (2002) from the Eocene Parisian amber. Charac- Aspock€ (2008). We generally accept their interpreta- ter states of the species without available specimens tion on the homologization of the genital sclerites were obtained using literature for guidance. Based on in Sialidae and use the gonocoxite-based terms our survey, 108 morphological characters obtained (gonocoxite, gonapophysis, and gonostylus) rather from adults (106, including 7 head, 12 thorax, 73 male than the neutral terms (parameres, gonarcus, etc.), genitalia, and 14 female genitalia) and larvae (2) were which were thought to be speciﬁc inventions of Neur- numerically coded (Appendix 1; Figs 1, 5–23). The opterida by Tjeder (1954). majority of coded characters stem from the genitalia (which, however, are missing in most fossil species) Morphological characters and a few extant species in which male specimens are unknown. Of 108 characters, 100 are binary and 8 are In their phylogenetic analyses, Nel et al. (2002) stud- multistate. Missing data were coded as “?”, and inap- ied wing venation, coding 18 characters; and Whiting plicable data as “–”. All characters were treated as (1994) studied male genitalia and a few other external unordered and with equal weight. 6 X. Liu et al. / Cladistics (2014) 1–32

Phylogenetic analysis Results

The phylogenetic analysis was performed in TNT Phylogenetic analysis ver. 1.1 (Goloboff et al., 2008) with an initial New Technology search set to 100 (using a driven search Phylogenetic analysis of the dataset including all with sectorial search, ratchet, drift, and tree fusing; alderfly taxa (matrix 1) with TNT yielded 53 MPTs. finding the minimum tree 10 times). An additional In the strict consensus tree from this dataset (Fig. 2a), “traditional search” based on 100 random addition Sialidae was monophyletic, but the internal relation- sequences was used to confirm the results of the New ships within Sialidae were poorly resolved and only a Technology search. First, we analysed the dataset few sister relationships within Sialis were recovered. including all alderfly taxa, namely matrix 1 (Table S1 The tree resolution was improved after pruning in Supporting information). Then we used the Pruned- some fossil species and extant species lacking male Trees option implemented in TNT ver. 1.1 (Goloboff representatives, and the relationships among most al- et al., 2008) to find improvements in tree resolution derfly genera were well resolved (see dataset in Table and support by finding and pruning certain wildcard S2). The strict consensus tree of 35 MPTs from this taxa. The branch support values were calculated with pruned dataset (matrix 2; Fig. 2b) firstly shows that the function implemented in TNT (tree bisection and †Sharasialis from the Upper Jurassic is the sister to reconnection, TBR, from existing trees, retain trees sub- the remaining ingroup taxa. Within the monophyletic optimal by 10 steps). Character states were mapped on Sialidae, Austrosialis is the sister to the remaining a most parsimonious tree (MPT) using WinClada ver. taxa, which are monophyletic. In this monophyletic 1.0 (Nixon, 2002), showing only unambiguous changes. group, Leptosialis and Stenosialis have sister relationships. The clade containing Haplosialis, †Eosialis,and Ancestral area reconstruction Indosialis forms a sister group to the five Neotropical species of Protosialis. The genera Nipponosialis and Based on the geographical distribution patterns of Sialis, as currently delimited, are not monophyletic. world alderfly genera, seven endemic areas were con- Two Nearctic Sialis species, S. americana and S. gla- sidered in this analysis: (a) eastern Australia (including bella, are grouped with Protosialis bifasciata from Tasmania); (b) southernmost Africa; (c) Madagascar; Cuba. The monophyletic group of these three species (d) South and Southeast Asia; (e) South America and is sister to the clade including the remaining species southern Central America (i.e. the present Neotropics); of Sialis, all species of Nipponosialis, and †Protosialis (f) southern half of North America; (g) Eurasia with voigti. The monophyly of Nipponosialis is not sup- exception of South and Southeast Asia, Middle East, ported. Since all nodes in the consensus tree have low large parts of Central and West Asia, and northern Bremer support values, we pruned all fossil taxa and part of Siberia (i.e. the Palaearctic realm with transi- extant taxa lacking male representatives (see dataset, tion zone between Palaearctic and Oriental realms; namely matrix 3, in Table S3). The parsimony analy- Fig. 4b). sis of matrix 3 obtained 14 MPTs. The strict consen- Ancestral areas at internal nodes were inferred using sus tree of these 14 MPTs (Fig. 3a) has largely a dispersal-vicariance (DIVA) optimization model identical intergeneric relationships with the results (Ronquist, 1997) implemented in the program from the matrix 2 dataset with pruned taxa, and all RASP2.0 Beta (Yu et al., 2011). The DIVA model nodes of the strict consensus tree reflected the inter- acknowledges the need for some level of dispersal in generic relationships of the matrix 2 dataset and the explaining the occurrence of widespread ancestors, and nodes comprising Protosialis + (Haplosialis + Indosial- the optimal ancestral reconstruction of the DIVA is) were supported with higher Bremer support values model is the least costly, i.e. the most parsimonious, (≥2). Furthermore, the phylogenetic relationships reconstruction. Since DIVA requires binary topology, within the monophyletic group comprising the species we used a fully resolved intergeneric phylogeny of of Nipponosialis and most species of Sialis had better Sialidae generated from the parsimony analysis based resolution. on the dataset with pruned taxa, namely matrix 2 (Table S2), for this analysis. In this binary tree, all ter- Ancestral area reconstruction minal taxa were confined at the genus level, and all extant genera plus two fossil genera, i.e. †Sharasialis The ancestral area reconstructed for all alderfly and †Eosialis, which have definite phylogenetic status, genera was eastern Australia, southernmost Africa, were included (Fig. 4a). The DIVA optimization was North America, and Eurasia (abfg). A combination conducted with default settings with the maximum of areas crossing Northern and Southern Hemispheres number of areas in ancestral ranges constrained to (abfg or abf) was reconstructed as the ancestral area four. for all Cenozoic alderfly genera. Similarly, a combina- X. Liu et al. / Cladistics (2014) 1–32 7

Fig. 2. Phylogenetic relationships among species of Sialidae, strict consensus trees based on analysis of: (a) matrix 1, which generated 53 MPTs; (b) matrix 2 with partial fossil and extant taxa pruned, which generated 35 MPTs. Bremer support values mapped on trees above branches. 8 X. Liu et al. / Cladistics (2014) 1–32

Fig. 3. Phylogenetic relationships of species of Sialidae, inferred from matrix 3 with all fossil taxa and extant taxa lacking male representatives pruned: (a) strict consensus tree of 14 MPTs, with Bremer support values mapped above branches; (b) selected tree of 14 MPTs, unambiguous apomorphies mapped on branches, black circles indicate nonhomoplasious changes, all valid genera and recognized species-groups are marked, names of genera follow taxonomic treatment based on present phylogenetic results. X. Liu et al. / Cladistics (2014) 1–32 9

(a)

(b)

Fig. 4. Historical biogeography of Sialidae. (a) Chronogram showing intergeneric relationships within Sialidae (after results of analysis of matrix 2, putative position of †Dobbertinia and †Proindosialis indicated by dotted lines), reconstructed ancestral areas mapped for each node, red circles indicate fossil records, numbers aside red circles show detailed information of relevant fossils: 1. †Sharasialis fusiformis from Late Jurassic of Mongolia; 2. †Dobbertinia reticulata from Early Jurassic of Germany; 3. †Austrosialis sp. from Palaeocene of Australia; 4. †Eosialis dorisi from the Eocene Parisian amber and Indosialis sp. from the Eocene Baltic amber; 5. †Indosialis beskonakensis from the Oligocene/Miocene of Turkey; 6. †Ilyobius baltica and †I. herrlingi from the Eocene Baltic amber; 7. †Ilyobius casca from the Miocene Dominican amber; 8. †Proindosialis cantalensis from Mio- cene of France; 9. †Sialis groehni and †S. voigti from the Eocene Baltic amber; 10. †Sialis muratensis from Miocene/Pliocene of France; 11. †Sialis strausi from Pliocene of Germany; thick branches indicate known extent of the fossil record; colour of branches corresponds to distribution areas of alderﬂy genera shown in Fig. 4b, branches with mixed colours indicate distribution across different areas; length of branches are estimated based on the date of putative divergence events; dashed lines indicate relevant divergence events with unknown date; geologic periods calibrated to a time scale in Myr placed at left, with rough images of palaeogeographical composition (by Ronald Blakey). (b) Endemic areas of world Sialidae, areas coded as follows: a, eastern Australia (including Tasmania); b, southernmost Africa; c, Madagascar; d, South and Southeast Asia; e, South America and southern Central America; f, southern half of North America; g, Eurasia with exception of South and Southeast Asia, Middle East, large parts of Central and West Asia, and northern part of Siberia. tion of areas crossing Northern and Southern Hemi- was reconstructed. Eurasia (g) was reconstructed as spheres (bfg, abfg, bf, or abf) was reconstructed for the ancestral area for the Ilyobius lineage, and within most Cenozoic alderﬂy genera except Austrosialis.A this lineage Madagascar plus Eurasia (with or without range in eastern Australia and southernmost Africa South and Southeast Asia) (cdg or cg) was recon- (ab) was reconstructed for the nodes of the sister pair structed as the ancestral area for the clade Haplosialis Stenosialis + Leptosialis. For the monophyletic clade + (Indosialis + †Eosialis). The ancestral area for the comprising the Ilyobius lineage and the Sialis lineage, Sialis lineage was reconstructed as North America (f) an area including North America and Eurasia (fg) only. 10 X. Liu et al. / Cladistics (2014) 1–32

(a) (b) (c)

(d) (e) (f)

(g) (h) (i) Fig. 5. Head and pronotum of alderﬂy adults, male: (a) Austrosialis maxmouldsi; (b) Stenosialis australiensis; (c) Leptosialis africana; (d) Haplosialis afra; (e) Indosialis bannaensis; (f) Ilyobius mexicana; (g) Protosialis americana; (h) Sialis kumejimae; (i) Sialis navasi. Scale bar = 1.0 mm.

Discussion (a) (b) Our investigation represents the ﬁrst phylogenetic study of Sialidae that spans all genera and most species. We discuss the results generated from the phylogenetic analysis based on matrix 3 (Fig. 3). These results uncovered a number of well supported clades and relationships within Sialidae. Support for these (c) (d) clades and their internal relationships are discussed Fig. 6. Labrum of alderﬂy adults: (a) Haplosialis afra, male; below. In addition, we also discuss the phylogenetic (b) Protosialis americana, male; (c) Sialis melania, male; (d) same, status of some fossil species based on the results from female. Scale bar = 1.0 mm. matrix 2 (Fig. 2b). X. Liu et al. / Cladistics (2014) 1–32 11

(a) (b)

(f) (g)

(h) (i)

Fig. 7. Mandibles of alderﬂy adults: (a) Ilyobius mexicana, male; (b) same, female; (c) Indosialis minora, male; (d) Protosialis glabella, male; (e) Sialis kunmingensis, male; (f) Sialis kumejimae, male; (g) same, female; (h) Sialis melania, male; (i) same, female. Scale bar = 1.0 mm.

Sialidae 2012b). Hence, based on the distinct differences in the larval morphology, it is plausible that †Sharasial- The monophyly of extant Sialidae is well supported is and all Cenozoic alderfly genera represent two sub- by a number of undisputed characters (Fig. 3b). The families, namely †Sharasialinae subfam. nov. (Type synapomorphies are the bifurcated Rs (char. 7 : 0), genus: †Sharasialis Ponomarenko, 2012; see diagnosis the MP vein with weak stem on the forewing (char. in Table S4), and Sialidinae. 13 : 1), the prothorax wider than long (char. 17 : 1), the bilobed fourth tarsomere (char. 18 : 1), the Extant genera from Afrotropical, Australian, and degeneration of the male gonocoxite 10 (char. Neotropical realms 58 : 1), the sclerotized female gonapophysis 8 (char. 100 : 0), the absence of the lateral tracheal gills on The alderflies from the southern Hemisphere are rare, the abdominal segment 8 of larvae (char. 106 : 1), and comprise the genera Austrosialis, Haplosialis, Lept- and the presence of the caudal filament on the osialis, Protosialis, and Stenosialis. Austrosialis and Ste- abdominal segment 10 of larvae (char. 107 : 1). How- nosialis are endemic to the Australian realm and are ever, it is worth mentioning that the larva of the fos- distributed only in costal area of eastern Australia and sil genus †Sharasialis from the Upper Jurassic of Tasmania. The monophyly of Austrosialis is supported Mongolia (Ponomarenko, 2012) has a pair of short by the dorsally curved male sternite 9 (char. 27 : 1; lateral tracheal gills on the abdominal segment 8 Fig. 9d) and the genus is recognized as the sister to the (similar to Corydalidae), which may represent the remaining extant alderflies, which are monophyletic due plesiomorphic condition in Megaloptera. Therefore, to the absence of the male gonocoxite 10 (char. 56 : 1) strictly speaking, the absence of the eighth pair of and the female gonocoxite 8 without a narrow longitu- larval lateral tracheal gills is a good synapomorphy dinal incision (char. 96 : 1). The other Australian genus for the extant Sialidae and a possible synapomorphy Stenosialis is monophyletic with several synapomor- for all Cenozoic Sialidae. Generally, Megaloptera phies, i.e. male sternite 9 directed posterodorsad and have rather conservative larval morphology. For thoroughly associated with tergite 9 (char. 25 : 1; example, the larvae of Chauliodinae have remained Fig. 10c), flattened male gonocoxite 9 (char. 29 : 1; almost unchanged in many important morphological Fig. 10b), male ectoproct ventrally with spinous bristles structures since the Middle Jurassic (Liu et al., (char. 38 : 1; Fig. 10b), male ectoproct partly fused 12 X. Liu et al. / Cladistics (2014) 1–32

(a) (b) (c)

(d) (e) (f)

(g) (h) (i)

(j)

(k) (l) Fig. 8. Wings of alderfly adults: (a) Austrosialis maxmouldsi; (b) Stenosialis australiensis; (c) Leptosialis necopinata; (d) Haplosialis afra; (e) Indosialis bannaensis; (f) Ilyobius mexicana; (g) Protosialis americana; (h) Sialis kumejimae; (i) Sialis sibirica; (j) †Dobbertinia reticulata, modified from Ansorge (2001); (k) †Eosialis dorisi, modified from Nel et al. (2002); (l) †Proindosialis cantalensis, modified from Nel (1988). Scale bar = 2.0 mm. with gonocoxite 11 (char. 41 : 1; Fig. 10b), and male Indosialis; this clade is supported by the largely exposed gonocoxite 11 proximally with spinous setae (char. male gonocoxite 9 in dorsal view (char. 32 : 1; 63 : 1) and with broadly subquadrate median processes Fig. 13a), the posterodorsally directed median pro- (char. 64 : 1; Fig. 10b). Interestingly, the two Austra- cesses of the male gonocoxite 10 (char. 60 : 1; Fig. 13c), lian alderfly genera are heterogeneous, and Stenosialis and the setose female gonapophyses 8 (char. 101 : 1; is the sister to the South African endemic genus Leptos- Fig. 12f). The male ectoproct with a slender, elongate, ialis, since in both the male ectoproct is largely paired and feebly sclerotized projection (char. 55 : 1; Fig. 12c) but medially fused by anteriorly convex and feebly and the female gonocoxite 8 with a narrow, longitudi- sclerotized region (chars 36 : 1, 37 : 1; Fig. 10a). The nal incision (char. 96 : 0; Fig. 12f) were mapped as the sister pair Stenosialis + Leptosialis is the sister to the autapomorphies of H. afra. It should be possible to monophyletic clade including Haplosialis, Indosialis, clarify the synapomorphies of the genus Haplosialis Protosialis, Nipponosialis, and Sialis with synapomor- when more data on H. madegassa become available, phies, such as the simple anterior branch of MP in both since the holotype, which is the only known specimen, wings (chars 8 : 1, 11 : 1) and the male gonocoxite 11 is lost. The Neotropical Protosialis is monophyletic but with vertically protruding median processes (char. weakly supported by the male endophallus with black- 77 : 1). The little known Malagasian endemic genus ish thorny setae (char. 90 : 1). The genus is the sister to Haplosialis is the sister to the Oriental endemic genus Haplosialis + Indosialis based on two synapomorphies: X. Liu et al. / Cladistics (2014) 1–32 13

(a) (b)

(e) (f)

Fig. 9. Austrosialis maxmouldsi Theischinger: (a) male genitalia, dorsal view; (b) male genitalia, ventral view; (c) male genitalia, lateral view; (d) male genitalia, caudal view; (e) female genitalia, lateral view; (f) female genitalia, ventral view. T7–9: seventh to ninth tergum; S7–9: seventh to ninth sternum; gp8: eighth gonapophyses; gx8, 9, and 11, eighth, ninth, and eleventh gonocoxite; gs9, ninth gonostylus; e, ectoproct. Scale bar = 1.0 mm. the completely paired male ectoproct (char. 36 : 2) and 9 : 1), the absence of the forewing sc crossvein (char. the specialized female gonapophyses 8 (char. 101 : 1/2). 10 : 1), and the paired female gonocoxite 8 (char. 94 : 1; Fig. 13f). Sialis and Nipponosialis form a Extant genera from Nearctic, Oriental, and Palaearctic monophyletic group, within which, however, both Sialis realms and Nipponosialis are paraphyletic. Synapomorphies for this clade include the male tergite 9 anteriorly with The extant alderﬂies from the Northern Hemisphere V-shaped internal apodeme (char. 21 : 1), the male ec- have a much richer species diversity than the sialid toproct largely fused with anus (char. 43 : 1), the fauna of the Southern Hemisphere and are widely dis- membranous female gonapophyses 8 (char. 100 : 1), tributed in the Nearctic, Palaearctic, and Oriental and the irregularly shaped female bursa copulatrix realms. All of them are placed into three genera: Sialis, with lateral projection and sclerotized ridges (char. Indosialis, and Nipponosialis. As discussed above, Ind- 104 : 1). A sister pair of two Nearctic Sialis species, osialis is the sister to the Malagasian genus Haplosialis, S. americana + S. glabella, are sister to the remaining and its monophyly is supported by the male left man- species of Sialis and Nipponosialis, which formed a dible being longer than the right mandible and having well supported monophyletic group based on a group two small inner teeth (chars 3 : 1, 5 : 1; Fig. 7c), the of synapomorphies: male mandibles with inner fossa forewing with posterior branch of MP simple (char. (char. 2 : 1), male left mandible with additional tooth 14 X. Liu et al. / Cladistics (2014) 1–32

(a) (b)

(e) (f)

Fig. 10. Stenosialis australiensis Tillyard: (a) male genitalia, dorsal view; (b) male genitalia, ventral view; (c) male genitalia, lateral view; (d) male genitalia, caudal view; (e) female genitalia, lateral view; (f) female genitalia, ventral view. Scale bar = 1.0 mm.

anterior to terminal tooth (char. 4 : 1), Rs vein of eyes (char. 0 : 1) and the distinctly broadened costal forewing with over three branches (char. 7 : 1), male region of the forewing (char. 14 : 1). tergite 9 nearly as long as wide (char. 19 : 1), male gonocoxites 9 close to each other (char. 28 : 1), Extinct genera male gonocoxite 11 with trace of median fusion on proximal plate (char. 59 : 1), and the truncate posterior Combining extant and extinct taxa into a single phy- margin of female sternite 7 (char. 92 : 0). Nipponosialis logenetic analysis is considered superior to the alterna- kumejimae is the sister to the monophyletic group tive method of analysing extant taxa ﬁrst, and then including N. jezoensis + N. kuwayamai and most Sialis adding the extinct taxa in a second step based on an species. The non-monophyly of Nipponosialis and its informal assessment of presumptive synapomorphies present relationships with Sialis are concordant with (Beutel et al., 2013). However, this approach cannot the synonymization of Nipponosialis under Sialis be always effective as evidence by the existing case, in proposed by New and Theischinger (1993). All Old which most fossil taxa lack a large number of phyloge- World Sialis and most Nearctic Sialis (S. americana + netic informative characters, e.g. the genitalic data. S. glabella excluded) are monophyletic and are Alternatively, by pruning certain taxa from the data supported by the feebly prominent male compound matrix, some relationships may be recovered. As X. Liu et al. / Cladistics (2014) 1–32 15

(a) (b)

(e) (f)

Fig. 11. Leptosialis necopinata Price, Liu, de Moor & Villet: (a) male genitalia, dorsal view; (b) male genitalia, ventral view; (c) male genitalia, lateral view; (d) male genitalia, caudal view; (e) female genitalia, lateral view; (f) female genitalia, ventral view. Scale bar = 1.0 mm. shown in the consensus tree from the matrix 3 dataset is somewhat similar to the results obtained by Nel with partial fossil and extant taxa pruned (Fig. 2b), et al. (2002) in which †Eosialis was grouped with Ind- the Upper Jurassic genus †Sharasialis could be consid- osialis and Leptosialis. Without knowledge of the geni- ered the most ancestral alderfly currently known. talic structure, the validity and phylogenetic status of Although the Lower Jurassic genus †Dobbertinia is the †Proindosialis remains unknown. Nonetheless, we con- earliest alderfly, its phylogenetic status is unclear. sider †Proindosialis to be distantly related to Indosialis There are two extinct genera from the Cenozoic, i.e. based on the strongly inflated costal region and the †Eosialis from the lower most Eocene and †Proindosi- MP vein with both main branches bifurcated in the alis from the Upper Miocene. †Eosialis formed a forewing. The branching condition of Rs was predicted monophyletic group with Indosialis with simple to be two-branched in †Proindosialis by Nel et al. anterior branch of MP and absence of the sc crossvein (2002). However, because the specimen is incomplete, in the forewing as synapomorphies. This relationship it cannot be ruled out that Rs is three-branched. If so, 16 X. Liu et al. / Cladistics (2014) 1–32

(a) (b)

(e) (f)

Fig. 12. Haplosialis afra (Navas): (a) male genitalia, dorsal view; (b) male genitalia, ventral view; (c) male genitalia, lateral view; (d) male genitalia, caudal view; (e) female genitalia, lateral view; (f) female genitalia, ventral view. Scale bar = 1.0 mm. the venation of †Proindosialis may indicate that this available. †Protosialis voigti has trifurcate Rs and is genus is probably a junior synonym of Sialis. Due to likely to be a species of Sialis, a view supported by the absence of data concerning the male endophallus, Fig. 2b. The generic placement of the other Cenozoic the three extinct species of Protosialis (†P. baltica, fossil alderflies with preserved adults remain as previ- †P. casca, and †P. herrlingi) are not grouped with the ously postulated: †Austrosialis sp. from the Palaeocene extant Neotropical Protosialis species in our analyses; of Australia, Indosialis sp. and †Sialis groehni from the instead, all might be closely related to each other due Eocene Baltic amber, †Indosialis beskonakensis from to similar venation, paired male ectoproct, and widely the Olio-Miocene of Turkey, and †Sialis muratensis separated male gonocoxite 9. Nevertheless, all extant from the Upper Miocene of France. Neotropical Protosialis have distinct coloration of alternate orange and black areas on head and prono- Generic classification tum, while †P. baltica and †P. herrlingi are mostly black, and the male tergite 9 in †P. herrlingi bears a Based on the phylogenetic analysis, a revised gen- pair of digitiform projections, which is shared by Lept- eric classification of Sialidae is presented. The family osialis as one of its autapomorphies. Therefore, the Sialidae comprises 12 valid genera and 87 valid spe- generic status of †P. baltica and †P. herrlingi needs cies. A world catalog of Sialidae is given in Table further clarification when more material becomes S4. X. Liu et al. / Cladistics (2014) 1–32 17

(a) (b)

(e) (f)

Fig. 13. Indosialis minora (Banks): (a) male genitalia, dorsal view; (b) male genitalia, ventral view; (c) male genitalia, lateral view; (d) male genitalia, caudal view; (e) female genitalia, lateral view; (f) female genitalia, ventral view. Scale bar = 1.0 mm.

The validity of the genus Protosialis is one of the of Sialis in that they lack the bilobed male labrum, most disputed questions in the taxonomy of Sialidae. specialized male mandibles with inner fossa, and trifur- Protosialis was erected by van der Weele (1909) for cate Rs veins, and these two species cannot be grouped three Neotropical alderflies (P. bifasciata, P. chilensis, with most Neotropical species of Protosialis. However, and P. mexicana) and one Nearctic species (S. ameri- P. bifasciata from Cuba was assigned to a monophy- cana), which is the type species of Protosialis. Ross letic group with S. americana and S. glabella based on (1937) synonymized Protosialis with Sialis, and this the female tergite 9 distinctly prominent on postero- treatment was supported by Whiting (1994). However, dorsal corner in lateral view in the results from the usage of the name Protosialis has not been abandoned dataset with partial fossil and extant taxa pruned since several Neotropical alderflies have subsequently (Fig. 2b). Therefore we consider S. americana, S. gla- been described as Protosialis by Penny (1981), Contre- bella, and P. bifasciata to belong to a genus separate ras-Ramos et al. (2005), and Contreras-Ramos (2006, from Sialis and most Neotropical Protosialis. Since 2008). Moreover, it must be mentioned that another S. americana is the type species of Protosialis, this genus name, Ilyobius, was erected for Sialis flavicollis genus is confirmed to be valid, but in a different sense Enderlein, 1910 by Enderlein (1910), but treated as a than previously conceived. Although the genus type of junior synonym of Protosialis by Penny (1981). In the Ilyobius (i.e. holotype of P. flavicollis) is poorly pre- present phylogenetic results (Fig. 3), five Neotropical served and its genitalia are lost, P. flavicollis should Protosialis species form a monophyletic group, which belong to the monophyletic group including P. flam- is to be considered as a valid genus. The Nearctic mata, P. mexicana,andP. ranchograndis based on the S. americana and S. glabella differ from other species similar cephalic marking patterns. In accordance with 18 X. Liu et al. / Cladistics (2014) 1–32

(a) (e)

(a)

(b) (f)

(b) (c) (g)

(d) (h) (c)

Fig. 14. Male genitalia of Ilyobius spp.: (a–d) Ilyobius chilensis (McLachlan), (a) dorsal view, (b) ventral view, (c) lateral view, (d) caudal view; (e–h) Ilyobius mexicana (Banks), (e) dorsal view, (f) ventral view, (g) lateral view, (h) caudal view. Scale bar = 1.0 mm.

this, Ilyobius should be reinstated as a valid genus that includes most Neotropical alderﬂies (except P. bifasciata).

Interspeciﬁc relationships (d)

Considering Ilyobius, the ﬁve extant species included Fig. 15. Female genitalia of Ilyobius spp.: (a–b) Ilyobius chilensis herein are separated into two species-groups. The Ilyo- (McLachlan), (a) lateral view, (b) ventral view; (c–d) Ilyobius mexica- bius chilensis group is composed of I. chilensis and na (Banks), (c) lateral view, (d) ventral view. Scale bar = 1.0 mm. X. Liu et al. / Cladistics (2014) 1–32 19

(a) (b)

(e) (f)

Fig. 16. Protosialis americana (Rambur): (a) male genitalia, dorsal view; (b) male genitalia, ventral view; (c) male genitalia, lateral view; (d) male genitalia, caudal view; (e) female genitalia, lateral view; (f) female genitalia, ventral view. Scale bar = 1.0 mm.

I. hauseri, and its monophyly is supported by the male head or dark markings around the compound eyes. sternite 9 with an elongate median protrusion (char. Since the head of I. flavicollis is uniformly orange, it 24 : 1; Fig. 14b), the hook-like male ectoproct (char. may also belong to this species-group. 54 : 1; Fig. 14c), the transversely band-like male gono- According to the taxonomic treatment and generic coxite 11 with short median processes (char. 88 : 1; classification of Sialidae, several species of Sialis from Fig. 14d), and the female gonocoxite 8 reduced and East Asia must have originated from a relatively ear- fused with gonapophyses 8 (chars 97 : 1, 99 : 1; lier divergence (see Fig. 3b). These include S. kumeji- Fig. 15b). Ilyobius nubila likely belongs to this species- mae, and three sister pairs: S. jezoensis + group since the female has gonocoxite and gonapophy- S. kuwayamai; S. kunmingensis + S. luohanbaensis;and ses 8 similar to those in I. chilensis and I. hauseri. The S. elegans + S. versicoloris. All North American and Ilyobius mexicana group is composed of I. flammata, European species, as well as a few Asian species, form I. mexicana, and I. ranchograndis, and its monophyly the crown group of Sialis. This group is supported by is supported by the male ectoproct largely paired but the male mandible without additional distal tooth medially connected by a very thin and feebly sclero- (char. 4 : 0), and can be separated into three main lin- tized region (char. 36 : 1; Fig. 14e), the male anus ven- eages, namely the S. lutaria lineage (monophyly sup- trally with a setose lobe (char. 91 : 1; Fig. 14h), and ported by the lingulate male sternite 9), the the female sternite 7 with an obtuse protrusion near S. infumata lineage (monophyly supported by the male posterior margin (char. 93 : 1; Fig. 15d). Adults of the ectoproct entirely sclerotized ventrally and the male I. mexicana group generally have a uniformly orange gonocoxite 11 with rather elongate and arcuately 20 X. Liu et al. / Cladistics (2014) 1–32

(a) (e) (i)

(b) (f) (j)

(d) (h) (l)

Fig. 17. Male genitalia of Sialis spp.: (a–d) Sialis jezoensis Okamoto, (a) dorsal view, (b) ventral view, (c) lateral view, (d) caudal view; (e–h) Sialis elegans Liu & Yang, (e) dorsal view, (f) ventral view, (g) lateral view, (h) caudal view; (i–l) Sialis luohanbaensis Liu, Hayashi & Yang, (i) dorsal view, (j) ventral view, (k) lateral view, (l) caudal view. Scale bar = 1.0 mm. curved median processes), and the S. sinensis lineage netic relationships among the species-groups of Sialis (monophyly supported by the transversely band-like were not resolved in the analysis by Whiting (1994). male sternite 9). The three lineages of Sialis recovered However, we recovered the S. infumata lineage as the in the present analysis are generally consistent with the sister to the S. sinensis lineage being supported by the previous hypothesis proposed by Whiting (1994), in shortened male sternite 9. Aside from the three spe- which the North American species of Sialis (except cies-groups recognized by Whiting (1994), we propose S. americana group, which is transferred to Protosialis) four other species-groups based on the present phylog- are separated into three species-groups, i.e. the S. aeq- eny, i.e. the S. lutaria group (comprising S. abchasica, ualis group (presently belonging to the S. lutaria line- S. klingstedti, S. levanidovae, S. lutaria, S. morio, age), the S. californica group (presently belong to the S. sordida, and S. zhiltzovae), the S. longidens group S. sinensis lineage), and the S. infumata group (pres- (comprising S. annae, S. biﬁda,andS. longidens), the ently belong to the S. infumata lineage). The phyloge- S. sinensis group (comprising S. henanensis, S. japon- X. Liu et al. / Cladistics (2014) 1–32 21

(a) (e) (i)

(b) (f) (j)

(d) (h) (l)

Fig. 18. Male genitalia of Sialis spp.: (a–d) Sialis nevadensis Davis, (a) dorsal view, (b) ventral view, (c) lateral view, (d) caudal view; (e–h) Sialis aequalis Banks, (e) dorsal view, (f) ventral view, (g) lateral view, (h) caudal view; (i–l) Sialis lutaria (Linnaeus), (i) dorsal view, (j) ventral view, (k) lateral view, (l) caudal view. Scale bar = 1.0 mm. ica, and S. sinensis), and the S. melania group (com- †Parasialidae, which is reported from the Late Permian prising S. melania, S. kyushuensis, S. tohokuensis, and (Ponomarenko, 1977), the earliest time of origin for S. toyamaensis). the Sialidae might be later than the Late Permian. Since all early Sialidae and stem groups of Megalopter- Origin of Sialidae a are from Eurasia, this landmass is thought to be the most likely place of origin for Sialidae. The earliest fossil of Sialidae currently known is †D. reticulata from the Early Jurassic (ca. 185 Ma) of Diversification of Sialidae Germany, which indicates that the family must have originated at least during the Early Jurassic. It is worth The diversification of Sialidae was initiated at least mentioning that the divergence date between Sialidae in the Jurassic since two genera are found in the Early and Corydalidae was estimated to be in the Late Trias- and Late Jurassic, respectively (Ansorge, 2001; Pon- sic (ca. 224 Ma) based on the mitochondrial genome omarenko, 2012). It is noticeable that the earliest data (Wang et al., 2012), or in the Early Permian (ca. alderfly genus †Dobbertinia is very similar to some 285 Ma), based on several nuclear and mitochondrial extant genera (e.g. Austrosialis) based on the nearly sequence data (Winterton et al., 2010). Both of these unchanged wing venation (Ansorge, 2001). Further, studies report a much earlier origin of Sialidae than the basal most alderfly genus †Sharasialis, which is the previously supposed. However, when considering one sole member of †Sharasialinae subfam. nov. and is of the putative stem groups of Megaloptera, i.e. considerably different from extant genera in larval 22 X. Liu et al. / Cladistics (2014) 1–32

†Sharasialis form a sister relationship, we could con- clude that the subfamilial diversification of Sialidae probably occurred at least during the Early Jurassic. However, it is difficult to test these hypotheses as long as we lack adult specimens of †Sharasialis and the larva of †Dobbertinia.If†Dobbertinia weretobemuch more closely related to the Cenozoic genera, the common ancestor of Sialidinae should have originated at (a) (e) least by the Early Jurassic. Although Eurasia is postulated to be the place of origin for Sialidae, the possible origin date for this family, which is prior to the breakup of the supercontinent Pangaea, shows that alderflies could have been widespread in Pangaea. Indeed, the present DIVA analysis also indicates a Pangaean origin for Sialidae in which Australia + Africa + Asia + North America represent the reconstructed ancestral area. Moreover, a similar ancestral area was also reconstructed for the (b) (f) clade that included all Cenozoic alderfly genera (major members of Sialidinae) and the subclade including most Cenozoic alderfly genera expect Austrosialis. Therefore it is suggested that the common ancestor of Sialidinae probably originated and was widespread in Pangaea during the Early Jurassic, and that an early divergence within Sialidinae might have also occurred prior to the breakup of the supercontinent. The splitting of Pangaea, especially the sequential breakup of Gondwana, is held to account for the (c) (g) diversification of various fauna during the Mesozoic (Sanmartın and Ronquist, 2004; Grimaldi and Engel, 2005). Penny (1993) proposed the hypothesis that the megalopteran subfamily Corydalinae had a Gondwa- nan origin based on the intergeneric phylogeny and the austral distribution of certain basal genera. Fur- ther, he mentioned that the other two major groups of Megaloptera (i.e. Chauliodinae and Sialidae) might have a similar model of origin from Gondwana. According to a recent study on the historical biogeography of Chauliodinae (Liu et al., 2012b), diversification in Gondwana and subsequent northward dispersal (d) (h) to Eurasia and North America during the Cretaceous and early Tertiary were recovered for a lineage including most fishfly genera, although Chauliodinae had Fig. 19. Male genitalia of Sialis spp.: (a–d) Sialis nigripes Pictet, been widely distributed in Pangaea during the Early (a) dorsal view, (b) ventral view, (c) lateral view, (d) caudal view; Jurassic. (e–h) Sialis infumata Newman, (e) dorsal view, (f) ventral view, (g) lateral view, (h) caudal view. Scale bar = 1.0 mm. Based on the present ancestral area reconstruction, the divergence between the Stenosialis lineage, which has an ancestral area restricted to the Southern Hemi- morphology, appeared much later than †Dobbertinia sphere, and the Ilyobius + Sialis lineage, which has an in the fossil record. Nevertheless, due to the early ancestral area restricted to the Northern Hemisphere, divergence of Sialidae, it is not surprising that the may be indicative of the separation between Laurasia †Sharasialis lineage might have originated much earlier and Gondwana. However, it is difficult to explain how than the Late Jurassic but has not been found before the Malagasian endemic genus Haplosialis in the Ilyo- this period due to the incompleteness of the fossil bius lineage migrated to their current distribution area record. The question remains whether †Dobbertinia from Laurasia, since Madagascar, as a landmass of also belongs to †Sharasialinae. If †Dobbertinia and Gondwana, was never largely connected to Laurasia X. Liu et al. / Cladistics (2014) 1–32 23

(a) (e) (i)

(b) (f) (j)

(d) (h) (l)

Fig. 20. Male genitalia of Sialis spp.: (a–d) Sialis longidens Klingstedt, (a) dorsal view, (b) ventral view, (c) lateral view, (d) caudal view; (e–h) Sialis melania Nakahara, (e) dorsal view, (f) ventral view, (g) lateral view, (h) caudal view; (i–l) Sialis sinensis Banks, (i) dorsal view, (j) ventral view, (k) lateral view, (l) caudal view. Scale bar = 1.0 mm. after the initial breakup of Pangaea (Sanmartın and nated before the breakup of Pangaea. Due to the Ronquist, 2004). Therefore some generic diversiﬁca- doubtful generic placement of the extinct Eocene tion, e.g. the splitting of Austrosialis and the diver- Ilyobius, the interpretation on the generic diversiﬁca- gence between the Stenosialis lineage and the Ilyobius tion within this lineage is still premature. Nevertheless, + Sialis lineage, must be unrelated to the breakup of the split between the Malagasian genus Haplosialis Pangaea. However, regarding the Stenosialis lineage, and the Eurasian genera †Eosialis + Indosialis, which we cannot eliminate the possibility that the divergence has Madagascar and Eurasia as the reconstructed between Stenosialis, which is endemic to Australia, and ancestral area for their common ancestor, is consistent Leptosialis, which is endemic to South Africa, was due with the divergence between Madagascar and India to the splitting apart of eastern Gondwana (Africa, during the Late Cretaceous (ca. 84 Ma) (Sanmartın India, Madagascar) and western Gondwana (all other and Ronquist, 2004). The northward drift of India southern landmasses) during the Early Cretaceous and its collision with Eurasia probably introduced the (Sanmartın and Ronquist, 2004; Grimaldi and Engel, ancestor of †Eosialis and Indosialis to Asia. After- 2005). ward, the ancestor of †Eosialis and Indosialis,asa Regarding the Ilyobius lineage, the ancestral area of new colonizer of Eurasia, possibly expanded its distri- this lineage was reconstructed as Eurasia. Similarly, as bution area eastward to Indochina and Sundaland and with the Malagasian endemic genus Haplosialis,we westward to Europe when these areas were tropical or hypothesize that this lineage also could have origi- warm temperate during the Eocene, while †Eosialis 24 X. Liu et al. / Cladistics (2014) 1–32

(a) (e) (i)

(b) (f) (j)

(c)

(g) (k)

(d) (h) (l)

Fig. 21. Male genitalia of Sialis spp.: (a–d) Sialis navasi Liu, Hayashi & Yang, (a) dorsal view, (b) ventral view, (c) lateral view, (d) caudal view; (e–h) Sialis sibirica McLachlan, (e) dorsal view, (f) ventral view, (g) lateral view, (h) caudal view; (i–l) Sialis californica Banks, (i) dorsal view, (j) ventral view, (k) lateral view, (l) caudal view. Scale bar = 1.0 mm. and the European Indosialis became extinct when their between the Ilyobius lineage and the Sialis lineage favorable warm habitats were reduced during the gla- took place before the breakup of Pangaea, the evolu- cial periods. The hypothesis that the common ancestor tionary history of the Sialis lineage could be much of some Eurasian endemic genera (e.g. †Eosialis and older than the Eocene. Although the present knowl- Indosialis) was introduced by the Indian subcontinent edge on prehistorical alderﬂies is very limited due to is therefore largely consistent with the Gondwanan the scarcity of fossil evidence, it is noticeable that origin (more exactly the Indian-origin) for the Asian certain genera (e.g. Ilyobius) currently distributed in endemic Corydalinae and Chauliodinae as proposed the Southern Hemisphere were once present in the by Penny (1993) and Liu et al. (2012b). Northern Hemisphere based on the fossil record, but Regarding the Sialis lineage, the ancestral area of neither fossil nor extant species related to the Sialis this lineage was reconstructed as North America. lineage has been found in the Southern Hemisphere. The earliest fossil record of this lineage is found in This scenario may suggest that the origin and diver- Eocene Baltic amber (Wichard, 1997), which indi- siﬁcation of the Sialis lineage occurred within the cates a divergence of this lineage no later than the Northern Hemisphere, possibly after the breakup of Eocene. As discussed above, if the divergence Pangaea. X. Liu et al. / Cladistics (2014) 1–32 25

(a) (e) (i)

(b) (f) (j)

(d) (h) (l)

Fig. 22. Female genitalia of Sialis spp.: (a–b) Sialis jezoensis Okamoto, (a) lateral view, (b) ventral view; (c–d) Sialis nevadensis Davis, (c) lateral view, (d) ventral view; (e–f) Sialis aequalis Banks, (e) lateral view, (f) ventral view; (g–h) Sialis lutaria (Linnaeus), (g) lateral view, (h) ventral view; (i–j) Sialis infumata Newman, (i) lateral view, (j) ventral view; (k–l) Sialis sinensis Banks, (k) lateral view, (l) ventral view. Scale bar = 1.0 mm.

The widespread distribution of Sialis is probably Conclusion due to a geological connection between North America and Eurasia. The Bering Bridge, which connected wes- The present research represents the most comprehen- tern North America and Asia from the Middle Creta- sive phylogeny of Sialidae to date, and is a crucial step ceous to the Late Pliocene (Sanmartın et al., 2001), in our understanding of the evolution of this ancient probably provided a significant route for the intercon- group. Based on the results of the phylogenetic analy- tinental faunal exchange of Sialis, which is demon- sis, the classification and intergeneric relationships of strated by the close relationships among certain Asian Sialidae are largely clarified (see key to genera of Siali- and North American alderflies (e.g. the monophyletic dae in Appendix 2). All Cenozoic genera form a S. sinensis lineage comprising many closely related monophyletic group, representing the subfamily Sialid- Asian and North American species). Moreover, the inae with the Jurassic genus †Sharasialis as a putative Thulean Bridge, which was the most important route sister taxa representing the subfamily †Sharasialinae for exchange of temperate biota between eastern subfam. nov. Of Cenozoic alderflies, the Australian North America and Europe in the Early Eocene (ca. endemic genus Austrosialis is sister to the remaining 55 Ma) (Sanmartın et al., 2001), might also account genera. The South African endemic genus Leptosialis for dispersals of Sialis across North America and Eur- and the Australian endemic genus Stenosialis form a ope. The sister relationship between S. nigripes from monophyletic Stenosialis lineage, which is sister to the Europe and the S. infumata group endemic to eastern Ilyobius and Sialis lineages. Within the Ilyobius line- North America would support the existence of this age, the Malagasian endemic genus Haplosialis and the intercontinental dispersal. Asian endemic genus Indosialis form a monophyletic 26 X. Liu et al. / Cladistics (2014) 1–32

Acknowledgements

We thank the following curators who kindly loaned or supplied specimens for this study: Dr L. Abrah am (Kaposvar), Dr U. Aspock€ (NHMW, Vienna), Dr D. Britton (AMS, Sydney), Ms. M. Cochrane (SAMC, Cape Town), J. Constant (IRSB, Brussels), Dr E. DeWalt and Dr P. P. Tinerella (INHS, Champaign), Dr O. S. Flint, Jr (USNM, Washington D.C.), Mr. D. Goodger and Dr B. W. Price (BMNH, London), Dr F. de Moor (AMGS, Grahamstown), Dr A. Nel (MNHN, Paris), Dr M. Ohl (MFN, Berlin), Dr M. Owada (NSMT, Tokyo), G. Sziraki (HNHM, Budapest), Dr M. Sartori (MZL, Lausanne), A. Taeger (SDEI, Muncheberg),€ Dr K. Yoshizawa (SEHU, Sapporo). Thanks are due to Dr John Plant (Vienna) for help with the English. We also appreciate two anonymous reviewers who provided valuable comments on this manuscript. This (a) (b) research was supported by the National Natural Sci- Fig. 23. Larvae of Sialidae: (a) Sialis sibirica McLachlan; (b) †Shar- ence Foundation of China (Nos. 31320103902 and asialis fusiformis Ponomarenko, modified from Ponomarenko (2012). 31322501), the National Key Basic Research Program Scale bar = 1.0 mm. of China (973 Program) (No. 2013CB127600), the Foundation for the Author of National Excellent Doctoral Dissertation of PR China (No. 201178), group, which is sister to the Neotropical endemic and a grant-in-aid for fellows of the Japan Society genus Ilyobius. †Eosialis from the Eocene Baltic amber for the Promotion of Science (JSPS) relating to the is tentatively included in the Ilyobius lineage. The Sial- JSPS Postdoctoral Fellowship for Foreign Research- is lineage comprises Protosialis and Sialis, while †Pro- ers (No. 20-08417). indosialis from the Upper Miocene of France might also belong to this lineage. However, most Neotropical alderflies previously placed in Protosialis are excluded References from this genus, and the present concept of the genus Sialis includes all species of the genus Nipponosialis. Ansorge, J., 2001. Dobbertinia reticulata Handlirsch 1920 from the Lower Jurassic of Dobbertin (Mecklenburg/Germany) — the The latter name is presently considered to be a syno- oldest representative of Sialidae (Megaloptera). N. Jb. Geol. nym of Sialis. Palaont.€ Mh. 2001, 553–564. The fossil record indicates that Sialidae might have Aspock,€ U., Aspock,€ H., 2008. Phylogenetic relevance of the genital originated by no later than the Early Jurassic. The sclerites of Neuropterida (Insecta: Holometabola). Syst. Entomol. 33, 97–127. ancestral area reconstruction for the main lineages of Aspock,€ H., Aspock,€ U., Holzel,€ H., 1980. Die Neuropteren Sialidae suggests a global distribution of alderflies in Europas: eine zusammenfassende Darstellung der Systematik, € Pangaea before their diversification. Furthermore, the Okologie und Chorologie der Neuropteroidea (Megaloptera, divergence of several lineages might have also occurred Raphidioptera, Planipennia) Europas. Goecke & Evers, Krefeld. before the breakup of Pangaea. However, the splitting Aspock,€ H., Holzel,€ H., Aspock,€ U., 2001a. Kommentierter Katalog of Pangaea, especially the sequential breakup of der Neuropterida (Insecta: Raphidioptera, Megaloptera, Gondwana, might account for some generic divergence Neuroptera) der Westpalaarktis.€ Denisia 2, 1–606. Aspock,€ U., Plant, J.D., Nemeschkal, H.L., 2001b. Cladistic analysis of Sialidae. Afterwards, the northward rafting of India of Neuroptera and their systematic position within Neuropterida during Late Cretaceous and Early Eocene introduced (Insecta: Holometabola: Neuropterida: Neuroptera). Syst. the common ancestors of various Cenozoic genera into Entomol. 26, 73–86. the Northern Hemisphere from the opposite side of Azam, K.M., Anderson, N.H., 1969. Life history and habits of Sialis rotunda and S. californica in western Oregon. Ann. Entomol. Earth. Soc. Am. 62, 549–558. Future studies on the phylogeny of Sialidae should Banks, N., 1920. New neuropteroid insects. Bull. Mus. Comp. Zool. focus on molecular systematics with comprehensive 64, 299–362. Barnard, K.H., 1931. The Cape alder-flies (Neuroptera, sampling. Time-calibrated phylogenies eventually will Megaloptera). Trans. R. Soc. S. Afr. 19, 169–184. revise the present estimates and further unravel the Beutel, R.G., Friedrich, F., 2008. Comparative study of larval head evolutionary history of these fascinating insects that structures of Megaloptera (Hexapoda). Eur. J. Entomol. 105, are, at least, 180 Myr old. 917–938. X. Liu et al. / Cladistics (2014) 1–32 27

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The ocelli are absent in all spe- Yang, D., Liu, X.Y., 2010. Fauna Sinica Insecta, Vol. 51, cies of Sialidae. Megaloptera. Science Press, Beijing. Yu, Y., Harris, A.J., He, X.J., 2011. RASP (Reconstruct Ancestral State in Phylogenies) 2.0 beta. http://mnh.scu.edu.cn/soft/blog/ Adult thorax RASP.

7 Forewing with Rs: (0) two-branched (Fig. 8a); (1) three- Supporting Information branched or more (Figs 8h,i). 8 Forewing with anterior branch of MP: (0) distally bifurcate Additional Supporting Information may be found in (Fig. 8a); (1) simple (Fig. 8d). the online version of this article: 9 Forewing with posterior branch of MP: (0) distally bifurcate Table S1. Dataset of matrix 1 for the present phylo- (Fig. 8a); (1) simple (Fig. 8e). 10 Forewing proximally with crossvein between C and Sc: (0) genetic analysis. present (Fig. 8f); (1) absent (Fig. 8e). Table S2. Dataset of matrix 2 for the present phylo- 11 Hindwing with anterior branch of MP: (0) distally bifurcate genetic analysis. (Fig. 8a); (1) simple (Fig. 8d). Table S3. Dataset of matrix 3 for the present phylo- 12 Hindwing with posterior branch of MP: (0) distally bifurcate genetic analysis. (Fig. 8c); (1) simple (Fig. 8d). Table S4. World catalog of Sialidae. 13 Forewing with stem of MP: (0) strong; (1) weak (Fig. 8j). 14 Forewing with costal region: (0) feebly broadened proximally (Fig. 8a); (1) strongly broadened proximally (Fig. 8i). Appendix 1 15 Forewing proximally with distinctly oblique costal crossveins: (0) absent (Fig. 8a); (1) present (Fig. 8c). Morphological characters coded in the phylogenetic 16 Wings with nygmata: (0) present; (1) absent. analysis 17 Prothorax: (0) longer than wide; (1) wider than long. 18 Legs with bilobed fourth tarsomere: (0) absent; (1) present.

Adult head Male genitalia

0 Male head with compound eyes: (0) strongly prominent 19 Tergite 9: (0) more than 2.0 times as wide as long (Fig. 9a); (Fig. 5a); (1) feebly prominent (Fig. 5i). The compound eyes are very (1) nearly as wide as long (Fig. 18e). In dorsal view the male tergite narrow and feebly prominent in males of all Sialis species except for 9 is short but distinctly wide in all species of Sialidae, except for S. americana and S. glabella. most species of Nipponosialis and Sialis in which the male tergite 9 is 1 Male labrum with posterior margin: (0) feebly concave as wide as long or even longer than wide. (Fig. 6a); (1) deeply concave (Fig. 6b); (2) bilobed (Fig. 6c). The 20 Tergite 9 with lateral projection: (0) absent; (1) angulate labrum is sexually dimorphic in Nipponosialis and Sialis. In males (Fig. 12c); (2) digitiform (Fig. 11c). The posterior margin of male of these genera, it is mostly bilobed, except for S. americana and tergite 9 is angulate to some degree in lateral view in H. afra and all S. glabella in which the labrum is deeply concaved on posterior Indosialis species. The digitiform lateral projection of the male tergite margin, while in females it is emarginate. 9 is a unique diagnostic character of Leptosialis, although it is also 2 Male mandibles with inner fossa: (0) absent (Figs 7a,c,d); (1) present in †P. herrlingi. present (Figs 7e,f,h). In Nipponosialis and Sialis, except S. americana 21 Tergite 9 anteriorly with internal apodeme: (0) arched and S. glabella, the male mandibles have a specialized and raised (Fig. 9a); (1) V-shaped (Fig. 18e). The male tergite 9 has its anterior inner margin, forming an inner fossa. internal apodeme posteriorly protruded medially, generally V-shaped X. Liu et al. / Cladistics (2014) 1–32 29 in dorsal view in Nipponosialis and Sialis, while the arcuate anterior it is paired and widely separated in H. afra, Indosialis, P. chilensis, internal apodome is shared by the remaining alderfly genera. and P. hauseri. An intermediate condition, in which the paired lat- 22 Sternite 9: (0) as long as or much longer than tergite 9 eral lobes of the male ectoproct are connected by feebly sclerotized (Fig. 9c); (1) shorter than but not fused with tergite 9 (Fig. 19c); (2) region, is present in Leptosialis, Stenosialis, and some Protosialis spe- shorter than and fused with tergite 9. A derived shortened male ster- cies. nite 9 is present in many Sialis species, while the short male sternite 37 Ectoproct medially with an anteriorly convex area connect- 9 is fused with tergite 9 in N. kumejimae. ing to paired lateral lobes: (0) absent; (1) present (Fig. 10a). Charac- 23 Sternite 9: (0) not lingulate; (1) lingulate (Fig. 18b). The lin- ter state (1) is present in Leptosialis and Stenosialis. gulate sternite 9 exhibits a broad and articulated subgenital plate 38 Ectoproct ventrally with spinous bristles: (0) absent; (1) pres- with a rounded apex in the S. lutaria group, the S. aequalis group, ent (Fig. 10c). S. fuliginosa, S. martynovae, S. nevadensis, and S. rotunda. 39 Ectoproct: (0) not flattened distally; (1) flattened distally 24 Sternite 9 with elongated median protrusion: (0) absent; (1) (Fig. 18i). The male ectoproct is dorsoventrally flattened on apex in present (Fig. 14b). An elongate median projection is present in two the S. lutaria group, S. aequalis, and S. contigua. species of Protosialis (P. chilensis and P. hauseri) and †E. dorisi (see 40 Ectoproct with long ventral protrusions: (0) absent; (1) Nel et al., 2002: Fig. 5). present, integrated with dorsal portion (see Ross, 1937: Fig. 31); 25 Sternite 9: (0) not directed posterodorsad; (1) directed pos- (2) present, distinguished from dorsal portion (see Ross, 1937: terodorsad and thoroughly associated with tergite 9 (Fig. 10c). Fig. 32). The male ectoproct posteroventrally protrudes into one Broad male sternite 9 normally has articulated connection with ter- or a pair of long projections in some species of the S. infumata gite 9, however, in Stenosialis sternite 9 is directed posterodorsad group, i.e. S. concava, S. hasta, S. mohri, and S. spangleri. How- and thoroughly associated with tergite 9, without any articulation. ever, the ventral protrusions are integrated with the dorsal portion 26 Sternite 9: (0) not transversely band-like; (1) transversely band- of the ectoproct in S. concava and S. hasta, while in S. mohri and like (Fig. 20b). The transversely band-like male sternite 9 is present in S. spangleri the ventral protrusions are distinguished from the ven- many Sialis species (the S. californica group, the S. sinensis group, tral portion of ectoproct by a visible suture. S. navasi, S. sibirica, and S. yamatoensis) and N. kumejimae. 41 Ectoproct and gonocoxite 11: (0) not fused with each other; 27 Sternite 9 subtrapezoidal with dorsally curved apex: (0) (1) partly fused with each other (Fig. 18k); (2) entirely fused with absent; (1) present (Fig. 9d). In Austrosialis the male sternite 9 is each other (Fig. 21c). The ectoproct is normally independent with subtrapezoidal with apex dorsally curved, having emarginate poster- the male gonocoxite 11; however, its ventral portion sometimes is ior margin. fused with the base of gonocoxite 11 in Stenosialis, the S. lutaria 28 Gonocoxite 9: (0) widely separated (Fig. 9b); (1) close to group, and S. martynovae, and even completely fused with gonocox- each other (Fig. 20b). The male gonocoxite 9 is paired, normally ite 11 into a single sclerotized complex in S. navasi. protruding from the posteroventral portion of tergite 9 and widely 42 Ectoproct with large, bulbed apex: (0) absent; (1) pres- separated from each other. However, Nipponosialis and most Sialis ent (Fig. 18b). In S. nevadensis and †S. groehni the male ectoproct is species have the male gonocoxite 9 close to each other. bilobed distally, with the apex of each lobe enlarged and bulbed. 29 Gonocoxite 9: (0) not flattened (Fig. 9d); (1) flattened or at 43 Ectoproct largely fused with anus: (0) absent; (1) present least proximally flattened (Fig. 17d). The male gonocoxite 9 is gener- (Fig. 18i). The male ectoproct is largely fused with the anus in Nip- ally bulged in most alderfly genera, but it is flattened, especially on ponosialis and Sialis. the proximal portion in N. jezoensis, N. kuwayamai, and most Sialis 44 Ectoproct entirely sclerotized and darkened ventrally: (0) species. absent; (1) present (Fig. 19b). The entire ventral surface of the 30 Gonocoxite 9: (0) not angulate ventrally; (1) angulate ventrally male ectoproct is sclerotized and darkened in S. nigripes and the (Fig. 20c). The male gonocoxite 9 is angulately prominent ventrally in S. infumata group. the S. californica group, the S. sinensis group, S. sibirica,andS. yama- 45 Ectoproct posteroventrally protruding as a tube-like sclerite: toensis. (0) absent; (1) present (Fig. 19e). In most species of the S. infumata 31 Gonocoxite 9 with apex: (0) not curved dorsad; (1) curved group the male ectoproct is somewhat fused on both dorsal and ven- dorsad (see Liu et al., 2008: Fig. 7). The apex of the male gonocox- tral surfaces and protruding posteroventrally, forming a tube-like ite 9 is curved dorsally in two Indosialis species (I. bannaensis and structure. I. indicus). 46 Ectoproct: (0) not elongated; (1) elongated (Fig. 19e). In 32 Gonocoxite 9: (0) largely covered by tergite 9 in dorsal view; S. concava, S. hasta, S. infumata, and S. nina the male ectoproct (1) largely protruding out of tergite 9 in dorsal view (Fig. 13a). In distinctly extends posteriorly in dorsal view as an elongated struc- all Indosialis species and H. afra the male gonocoxite 9 is distinctly ture. protruding out of the tergite 9 in dorsal view. 47 Ectoproct: (0) not hexagonal; (1) hexagonal (see Ross, 1937: 33 Gonocoxite 9: (0) not triangular; (1) small and subtriangular Fig. 28). In S. itasca and S. velata the male ectoproct presents as a with round apex (Fig. 16b). The male gonocoxite 9 is small and sub- small sclerite, which is hexagonal in caudal view. triangular with a round apex in S. americana and S. glabella. 48 Ectoproct with narrowed apex angulately bended ventrally: 34 Gonocoxite 9 subquadrate, laterally with an obtuse and (0) absent; (1) present (Fig. 20g). In S. sinensis, S. japonica, and the upright projection: (0) absent; (1) present (Fig. 17b). The male gono- S. melania complex the apex of the male ectoproct is narrowed and coxite 9 is subquadrate and laterally has an obtuse and upright pro- bended ventrally, which in lateral view makes the posterior margin jection in N. jezoensis and N. kuwayamai. of ectoproct medially angulate. 35 Gonostylus 9: (0) present (Fig. 18c); (1) absent. The gono- 49 Ectoproct with acutely produced apex: (0) absent; (1) present stylus 9 is absent in most Chauliodinae and Sialidae but present in (Fig. 20g). In S. melania and S. tohokuensis the apex of male ecto- Corydalinae. However, in S. nevadensis the gonostylus 9 still proct is narrowed and acutely produced. remains. 50 Ectoproct with densely setose apex: (0) absent; (1) present. 36 Ectoproct: (0) ring-like around anus (Fig. 17l); (1) largely In S. toyamaensis and S. kyushuensis the apex of male ectoproct is paired but medially connected by feebly sclerotized region (Fig. 10a); feebly sclerotized and densely setose. (2) paired and completely separated (Fig. 12a). The male ectoproct 51 Ectoproct with base ventrally protruding and strongly sclero- is ring-like and fused with anus in most species of Sialidae, however, tized: (0) absent; (1) present (see Ross, 1937: Fig. 20). In S. driesbachi 30 X. Liu et al. / Cladistics (2014) 1–32 and S. hamata the base of the male ectoproct is protruded ventrally is generally as long as or longer than ectoproct in most alderfly spe- into a strongly sclerotized projection. cies, but it is shortened into a hook-like sclerite in the S. californica 52 Ectoproct with thickened ventral margin: (0) absent; (1) group, S. sibirica, and S. yamatoensis. present (Fig. 18k). The ventral margin of male ectoproct is strongly 66 Gonocoxite 11 proximally fused with specialized membrane: sclerotized in Nipponosialis and Sialis, but this sclerotized ventral (0) absent; (1) present (Fig. 21k). The male gonocoxite 11 generally margin is distinctly thickened in S. klingstedti, S. lutaria, S. levanido- connects with tergite 9 by a membrane in Sialidae. This membrane is vae, S. morio, and S. sordida. posteriorly produced and more or less expanded in the S. californica 53 Ectoproct with subquadrate apex: (0) absent; (1) present group, the S. sinensis group, S. sibirica, S. yamatoensis, and †S. gro- (Fig. 18i). The male ectoproct is generally narrowed toward apex in ehni. Sialidae, but in S. lutaria, S. morio, and S. sordida the male ecto- 67 Gonocoxite 11 with tube-like membranous lobes: (0) absent; proct has a broadly subquadrate apex without a distinct notch. (1) present (Fig. 18i). In the S. lutaria group, S. abchasica, S. aequal- 54 Ectoproct: (0) not hook-like; (1) hook-like (Fig. 14c). The is, S. contigua, and S. zhiltzovae the male gonocoxite laterally bears male ectoproct exhibits as a pair of hook-like lobes in P. chilensis. a pair of tube-like membranous lobes. Similarly, in P. hauseri there is a pair of hook-like lobes, which are 68 Gonocoxite 11 with internal sclerotization on tube-like mem- strongly curved inward. Contreras-Ramos et al. (2005) considered branous lobes: (0) absent; (1) present (see Vshivkova, 1985: Fig. 1a). the male ectoproct as lost in P. hauseri and interpreted the paired The tube-like lobes on the male gonocoxite 11 are completely mem- lobes as sternite 10. It is very doubtful that male Sialidae lack the ec- branous in the S. lutaria group, S. aequalis, and S. contigua, but toproct. Due to the close affinity of P. chilensis with P. hauseri,we they have internal sclerotization in S. abchasica and S. zhiltzovae. predict that the male ectoproct should also be hook-like and that the 69 Gonocoxite 11 with a proximal plate: (0) present; (1) absent male gonocoxite 11 (i.e. sternite 10 in Contreras-Ramos et al., 2005) (Fig. 21l). In the S. californica group and S. sibirica the gonocoxite might also be inconspicuous in P. hauseri. lacks a distinct proximal plate. 55 Ectoproct with a slender, elongate and feebly sclerotized 70 Gonocoxite 11 laterally with transparent areas: (0) absent; projection: (0) absent; (1) present (Fig. 12c). Character state (1) is (1) present (Figs 18d,k). The tube-like membranous lobes mentioned present only in †E. dorisi and H. afra. above protrude from transparent areas of the male gonocoxite 11, 56 Gonocoxite 10: (0) present (Fig. 9d); (1) absent. The male while in S. martynovae and S. nevadensis similar transparent areas gonocoxite 10 is absent in most alderfly species; however, it remains are also present but the tube-like lobes are absent. as one or a pair of small sclerites in Austrosialis, S. abchasica, 71 Gonocoxite 11 with tube-like membranous lobes: (0) bald S. levanidovae, S. morio, S. sordida, and S. zhiltzovae. (Fig. 18i); (1) setose (see Vshivkova, 1985: Fig. 2b). The tube-like 57 Gonocoxite 10: (0) paired (Fig. 9d); (1) unpaired (see Vshivk- membranous lobes of the male gonocoxite 11 are bald in S. ab- ova, 1985: Fig. 2h). The remnant of male gonocoxite 10 is paired in chasica, S. levanidovae, S. lutaria, S. sordida, and S. zhiltzovae, but Austrosialis but unpaired in the Sialis species that have this sclerite. bear short setae in S. klingstedti and S. morio. 58 Gonocoxite 10: (0) well developed; (1) degenerated or 72 Gonocoxite 11, width: (0) >0.29 mm; (1) <0.15 mm (see absent. The male gonocoxite 10 is well developed and presents as a Whiting, 1994: Fig. 23). In S. arvalis and S. bilobata the male gono- distinct sclerite in Corydalidae, but it is degenerated or absent in coxite 11 is extremely small, with a width <0.15 mm. Sialidae. 73 Gonocoxite 11 medially with pterygoid lateral plate: (0) 59 Gonocoxite 11 with proximal plate: (0) bearing no trace of absent; (1) present (Fig. 20l). In S. henanensis, S. japonica, and median fusion (Fig. 12d); (1) bearing trace of median fusion S. sinensis the male gonocoxite 11 possesses lateral projections in the (Fig. 17h). The male gonocoxite 11 has a single, transversely wide middle, which is pterygoid in caudal view. proximal plate in most alderfly genera except Nipponosialis and Sialis 74 Gonocoxite 11 with base: (0) close to tergite 9; (1) widely (excluding S. americana and S. glabella), which have the base of apart from tergite 9 (Fig. 20k). The male gonocoxite 11 is close male gonocoxite 11 paired and more or less fused medially. to the tergite 9 in most alderfly species; however, it is very pos- 60 Gonocoxite 11 with median processes: (0) directed postero- teriad and widely separated from tergite 9 in the S. californica ventrad (Fig. 9c); (1) directed posterodorsad (Fig. 12c). The male group, S. annae, S. bifida, S. henanensis, S. klingstedti, S. levani- gonocoxite has a pair of posteroventrally directed median processes dovae, S. longidens, S. lutaria, S. morio, S. sibirica, S. sinensis, in most alderfly species, but in H. afra and Indosialis the median S. sordida,andS. yamatoensis. processes are directed posterodorsad. 75 Membrane proximal to gonocoxite 11: (0) not posteriorly 61 Gonocoxite 11 with elongate and arcuately curved median tapering; (1) posteriorly tapering (Fig. 21k). In the S. californica processes: (0) absent; (1) present (Fig. 19g). The median processes of group, S. sibirica and S. yamatoensis the membrane connecting male gonocoxite 11 are relatively short and straightly directed in proximal portion of the male gonocoxite 11 is produced posteri- most alderfly species, while they are elongate and arcuately curved in orly. the S. infumata group and S. nigripes. 76 Membrane proximal to gonocoxite 11: (0) not transversely 62 Gonocoxite 11 with an additional short lobe beneath median expanded; (1) transversely expanded and strongly ruffled (Fig. 20d). processes: (0) absent; (1) present (Fig. 19g). In some species of the The membrane connecting proximal portion of the male gonocoxite S. infumata group there is an additional short lobe, which is dis- 11 is transversely expanded and strongly ruffled in several Asian Si- tinctly visible in lateral view, beneath the median processes of the alis species, including S. annae, S. bifida, S. henanensis, S. japonica, male gonocoxite 11. S. longidens, S. sinensis, and the S. melania complex. 63 Gonocoxite 11 with median processes: (0) attenuate; (1) 77 Gonocoxite 11: (0) broadly shield-like, without vertically broadly subquadrate (Fig. 10b). The median processes of the male protruding median processes (Fig. 11c); (1) band-like or claw-like, gonocoxite 11 are generally attenuate in most alderfly species, but with vertically protruding median processes (Fig. 12d). The male they are broadly subquadrate in Stenosialis. gonocoxite 11 is broadly shield-like and has the median processes 64 Gonocoxite 11 proximally with spinous setae: (0) absent; (1) not vertically protruding in Austrosialis, Leptosialis, and Stenosialis. present (Fig. 10c). In Stenosialis the male gonocoxite 11 bears In the remaining alderfly taxa the male gonocoxite 11 is relatively numerous short spinous setae on proximal portion. small, claw-like, or has the median processes vertically protruding 65 Gonocoxite 11: (0) nearly as long as or longer than ecto- from a band-like proximal plate. proct; (1) shorter than ectoproct (Fig. 21l). The male gonocoxite 11 X. Liu et al. / Cladistics (2014) 1–32 31

78 Gonocoxite 11 with butterfly-shaped proximal plate: (0) ventral view with a truncate posterior margin in Nipponosialis and absent; (1) present (Fig. 19f). The butterfly-shaped proximal plate of most Sialis species. In the remaining alderfly taxa the female sternite the male gonocoxite 11 is present only in the S. infumata group. 7 is more or less produced posteriorly. 79 Gonocoxite 11 with median processes being extremely thin 93 Sternite 7 with obtuse protrusion: (0) absent; (1) present at apex: (0) absent; (1) present (Fig. 19f). The median processes of (Fig. 15d). In P. mexicana and P. ranchograndis the female sternite 7 the male gonocoxite 11 has very thin apices in several species of the bears an obtuse protrusion near posterior margin. S. infumata group, including S. concava, S. hasta, S. infumata, 94 Gonocoxite 8: (0) unpaired, with median depression or inci- S. itasca, S. nina, and S. velata. sion (Fig. 9f); (1) paired (Figs 11f, 13f). The female gonocoxite 8 is a 80 Gonocoxite 11 with proximal plate laterally broadened: (0) single sclerite with either a median depression or incision in most al- absent; (1) present (Fig. 20d). The proximal plate of the male gono- derfly species, but in Indosialis and Leptosialis it is paired and widely coxite 11 is generally gradually narrowed laterally, but in S. annae, separated. S. bifida, and S. longidens the proximal plate is pterygoid and broad- 95 Gonocoxite 8 posteriorly with a U-shaped median incision: ened laterally. (0) absent; (1) present (Fig. 22f). In S. aequalis, S. contigua, and 81 Gonocoxite 11 with base posterior to apex of ectoproct: (0) S. vagans the posterior female gonocoxite 8 has a U-shaped median absent; (1) present (Fig. 21k). This character refers to the position of incision. the male gonocoxite 11. In most alderfly species the male gonocoxite 96 Gonocoxite 8 with a narrow longitudinal median incision: 11 is close to the base or subdistal portion of ectoproct, but in (0) present (Figs 9f, 12f); (1) absent. The female gonocoxite 8 pos- S. californica, S. driesbachi, S. hamata, and S. occidens it extends sesses a narrow, longitudinal, median incision in some basal fishfly beyond the apex of ectoproct. genera and a few alderfly genera (i.e. Austrosialis and Haplosialis), 82 Gonocoxite 11 heart-shaped in caudal view: (0) absent; (1) but the median incision is absent in most alderfly species. present (Fig. 21l). In S. californica, S. cornuta, S. driesbachi, S. ha- 97 Gonocoxite 8: (0) well developed (Fig. 9f); (1) reduced mata, S. joppa, and S. occidens the male gonocoxite exhibits a small (Fig. 15b). The female gonocoxite 8 is reduced to a very small genital hook, which is nearly heart-shape in caudal view. setose sclerite in P. nubila and is even absent in P. chilensis and 83 Gonocoxite 11 dorsally rounded in caudal view: (0) absent; P. hauseri. (1) present (Fig. 21l). This character refers to the small male gono- 98 Gonocoxite 8 with broad, deep posterior incision: (0) absent; coxite 11 in some species of the S. californica group. In S. californi- (1) present (see Vshivkova, 1985: Fig. 5c). The female gonocoxite is ca, S. driesbachi, and S. hamata the male gonocoxite 11 is paired arched with lateral portions posteriorly curved, forming a broad and and each lobe is dorsally rounded in caudal view. deep posterior incision in S. klingstedti and S. levanidovae. 84 Gonocoxite 11 dorsolaterally spinous in caudal view: (0) 99 Gonocoxite 8 and gonapophyses 8: (0) not fused (Fig. 9f); absent; (1) present. In S. cornuta and S. joppa the male gonocoxite (1) fused (Fig. 15b). The female gonocoxite 8 is separated from the 11 is prominent dorsolaterally forming a spinous projection. gonapophyses in most alderfly species, but in P. bifasciata, P. chilen- 85 Gonocoxite 11 with dorsal protrusion: (0) absent; (1) present sis, P. hauseri, and P. nubila the gonocoxite 8 is reduced and fused (Fig. 18k). In the S. lutaria group, S. abchasica, S. martynovae, and with the gonapophyses. S. zhiltzovae the male gonocoxite 11 is produced dorsally into a pro- 100 Gonapophyses 8: (0) sclerotized (Fig. 15b); (1) membra- trusion nearly reaching the ectoproct. nous (Fig. 22b). The female gonapophyses is a singular plate, which 86 Gonocoxite 11 with median processes expanded anteroventral- is membranous in Nipponosialis and Sialis; however, in the remain- ly: (0) absent; (1) present (Fig. 19h). The median processes are expanded ing alderfly genera it is partially or completely sclerotized. anteroventrally in N. kumejimae, S. elegans, and S. versicoloris. 101 Gonapophyses 8: (0) bald (Fig. 9f); (1) setose (Figs 12f, 87 Gonocoxite 11 with median processes straightly directed 13f). The female gonapophyses lacks setae in most alderfly species, ventrad and hook-like at tip: (0) absent; (1) present (Fig. 19k). This but is setose in Indosialis and H. afra. character state is present only in two Oriental Sialis species, i.e. 102 Gonapophyses 8: (0) small and subtriangular (Fig. 22b); S. kunmingensis and S. luohanbaensis. (1) broadly shield-like (Figs 13f, 15b); (2) transversely arcu- 88 Gonocoxite 11 transversely band-like with short median pro- ate (Figs 12f, 15d). The female gonapophyses 8 is small, subtrian- cesses: (0) absent; (1) present (Fig. 14d). In P. chilensis and P. hau- gular, and sometimes inconspicuous in most alderfly species. But seri the male gonocoxite 11 is inconspicuous and exhibits a it is a broad and shield-like plate in Indosialis, L. necopinata, transversely band-like sclerite with a short median processes. P. chilensis, and P. hauseri. It is also modified into a transversely 89 Gonocoxite 11 separated into a pair of concave plates: (0) directed and arcuate plate in H. afra, P. mexicana, and P. rancho- absent; (1) present (Fig. 18h). The paired and concave plates of the grandis. male gonocoxite 11 are present in S. aequalis, S. contigua, 103 Tergite 9 with a distinctly prominent posterodorsally mar- S. rotunda, and S. vagans. gin: (0) absent; (1) present (Fig. 16e). In P. bifasciata, S. americana, 90 Endophallus with thorny setae: (0) absent; (1) present and S. glabella the female tergite 9 in lateral view is distinctly promi- (Fig. 14d). The eversible sac between sternite 9 and gonocoxite nent on the posterodorsal margin. 11 in Protosialis mentioned by Contreras-Ramos (2008) is homol- 104 Bursa copulatrix: (0) simply ovoid, without lateral projec- ogized with the endophallus, which is reduced in most alderfly tion or sclerotized ridge (Fig. 15a); (1) irregularly shaped with lat- species. However, in most Protosialis species, the endophallus is eral projection and sclerotized ridges (Fig. 22a). The bursa distinct and has blackish thorny setae. copulatrix is a membranous sac-like structure with an opening 91 Anus ventrally with setose lobe: (0) absent; (1) present between gonocoxite 8 and tergite 9. In Indosialis, Leptosialis, Prot- (Fig. 14h). A setose lobe is present beneath the male anus in P. flam- osialis, Stenosialis, and H. afra the bursa copulatrix is simple and mata, P. mexicana, and P. ranchograndis. generally ovoid. In Nipponosialis and Sialis it is highly variable in shape among the species, but generally it is more or less produced laterally and bears sclerotized ridges. Female genitalia 105 Cercus: (0) well developed with rosette trichobothria; (1) degenerated. In Sialidae the cercus is reduced without rosette trichobothria. 92 Sternite 7 with posterior margin: (0) truncate (Fig. 22b); (1) produced (Fig. 10f). The female sternite 7 is a subquadrate plate in 32 X. Liu et al. / Cladistics (2014) 1–32

Larva 107 Larva with caudal ﬁlament on abdominal segment 10: (0) absent; (1) present (Fig. 23). 106 Larva with a pair of lateral tracheal gills on abdominal segment 8: (0) present (Fig. 23b); (1) absent (Fig. 23a).

Appendix 2

Key to adults of world genera of Sialidae

1. Forewing with both main branches of MP distally bifurcated or with MA and both branches of MP simple 2 Forewing with simple anterior branch and distally bifurcated posterior branch of MP or with MA distally 6 bifurcated and MP with both main branches simple 2. Forewing with costal area distinctly inﬂated proximally, and with posterior fork ca. 2.0 times as long as †Proindosialis Nel anterior fork of MP (Fig. 8l); Europe Forewing with costal area feebly inﬂated proximally and with posterior fork ca. 0.8–1.5 times as long as 3 anterior fork of MP, or with MA and both branches of MP simple 3. Crossveins between R and Rs vertical to both R and Rs, or with one or two crossveins forming a pointed 4 angle at R proximally and at Rs distally on forewing (Fig. 8a); male tenth gonocoxite present as a pair of feebly sclerotized lobes (Austrosialis) (Fig. 9b) Crossveins between R and Rs with one or two crossveins forming a pointed angle at R distally and at Rs 5 proximally on forewing (Figs 8b,c); male tenth gonocoxite absent 4. Distal fork of Rs nearly as long as stem part distal to branching point of Rs and MA on forewing (Fig. 8a); Austrosialis Tillyard Australia Distal fork of Rs ca. 0.3 times as long as stem part distal to branching point of Rs and MA on forewing †Dobbertinia Handlirsch (Fig. 8j); Europe 5. Forewing proximally without distinctly oblique costal crossveins (Fig. 8b); male tergite 9 laterally without Stenosialis Tillyard projection (Fig. 10c); male ectoproct ventrally with spinous bristles (Fig. 10d); female gonocoxite 8 unpaired (Fig. 10f); Australia Forewing proximally with distinctly oblique costal crossveins (Fig. 8c); male tergite 9 laterally with a pair of Leptosialis Esben-Petersen digitiform projection (Fig. 11c); male ectoproct ventrally without spinous bristles; female gonocoxite 8 paired (Fig. 11f); South Africa 6. Rs distally 2-branched in both fore- and hindwings; male mandibles without inner fossa; male tergite 9 7 more than 2.0 times as wide as long; male gonocoxite 9 widely separated; female sternite 7 distinctly convex posteriorly Rs distally 3 or 4-branched in both fore- and hindwings (Figs 8h,i); male mandibles with inner fossa Sialis Latreille (Figs 7e,f,h); male tergite 9 nearly as wide as long; male gonocoxite 9 close to each other; female sternite 7 with truncate posterior margin or feebly prominent medially (S. nevadensis); Asia, Europe and North America 7. Forewing with both main branches of MP simple 8 Forewing with simple anterior branch and distally bifurcated posterior branch of MP 9 8. Male sternite 9 without an elongate median lobe; male ectoproct without a slender, elongate and feebly Indosialis Lestage sclerotized projection; Europe (only fossil records), South and Southeast Asia Male sternite 9 with an elongate median lobe; male ectoproct with a slender, elongate and feebly sclerotized †Eosialis Nel, Menier, projection; Europe De Plo€eg, Hodebert & Danvin 9. Male gonocoxite 9 small, subtriangular (Fig. 16c); male ectoproct ring-like around anus (Fig. 16d); female Protosialis van der Weele tergite 9 with a distinctly prominent posterodorsal margin (Fig. 16e); United States and Cuba Male gonocoxite 9 broad; male ectoproct widely separated from anus; female tergite 9 with posterodorsal 10 margin not prominent 10. Male ectoproct with a slender, elongate and feebly sclerotized projection (Fig. 12c); female gonapophyses Haplosialis Navas laterally setose (Fig. 12f); Madagascar Male ectoproct without a slender, elongate and feebly sclerotized projection; female gonapophyses entirely Ilyobius Enderlein bald; Europe (only fossil records), Central and South America