A Remarkable New Family of Jurassic Insects (Neuroptera) with Primitive Wing Venation and Its Phylogenetic Position in Neuropterida

Background Lacewings (insect order Neuroptera), known in the fossil record since the Early Permian, were most diverse in the Mesozoic. A dramatic variety of forms ranged in that time from large butterfly-like Kalligrammatidae to minute two-winged Dipteromantispidae. Principal Findings We describe the intriguing new neuropteran family Parakseneuridae fam. nov. with three new genera and 15 new species from the Middle Jurassic of Daohugou (Inner Mongolia, China) and the Early/Middle Jurassic of Sai-Sagul (Kyrgyzstan): Parakseneura undula gen. et sp. nov., P. albomacula gen. et sp. nov., P. curvivenis gen. et sp. nov., P. nigromacula gen. et sp. nov., P. nigrolinea gen. et sp. nov., P. albadelta gen. et sp. nov., P. cavomaculata gen. et sp. nov., P. inflata gen. et sp. nov., P. metallica gen. et sp. nov., P. emarginata gen. et sp. nov., P. directa gen. et sp. nov., Pseudorapisma jurassicum gen. et sp. nov., P. angustipenne gen. et sp. nov., P. maculatum gen. et sp. nov. (Daohugou); Shuraboneura ovata gen. et sp. nov. (Sai-Sagul). The family comprises large neuropterans with most primitive wing venation in the order indicated by the presence of ScA and AA1+2, and the dichotomous branching of MP, CuA, CuP, AA3+4, AP1+2. The phylogenetic position of Parakseneuridae was investigated using a phylogenetic analysis of morphological scoring for 33 families of extinct and extant Neuropterida combined with DNA sequence data for representatives of all extant families. Parakseneuridae were recovered in a clade with Osmylopsychopidae, Prohemerobiidae, and Ithonidae. Conclusions/Significance The presence of the presumed AA1+2 in wings of Parakseneuridae is a unique plesiomorphic condition hitherto unknown in Neuropterida, the clade comprising Neuroptera, Megaloptera, Raphidioptera. The relative uncertainty of phylogenetic position of Parakseneuridae and the majority of other families of Neuroptera reflects deficient paleontological data, especially from critical important periods for the order, earliest Triassic and latest Triassic/earliest Jurassic.

among Symphrasinae, Mesomantispinae) have state (1), but the majority of other genera (including the Early Jurassic Liassochrysa Ansorge et Schlüter) have state (0) which is used for the analysis.
Comments. Nymphidae, Prohemerobiidae, Ithonidae and Psychopsidae are polymorphic for this character. In Nymphidae, state (2) occurs in the most species of Myiodactylinae, and state (3) in the most species of Nymphinae and the vast majority of fossil taxa. In Prohemerobiidae, state (1) occurs in a few species that possess the strongly recurrent and branched humeral veinlet; state (0) in other species. The same situation is in Ithonidae. State (0) is used for the analysis in these families. In Psychopsidae, some fossil genera (e.g., Undulopsychopsis Peng et al: Figure 2 in [33]) have state (1), whereas all extant and some fossil genera (e.g., Baisopsychops Makarkin: Figure 1 in [34]) possess state (2), which is used for the analysis. Comments. Osmylidae is polymorphic for this character. The subcostal space is narrow in most extant genera (state 0), and very broad in an undescribed Jurassic subfamily (state 2). However, the most primitive fossil taxa (including Protosmylinae, Archaeosmylidia Makarkin et al.: [36]) possess state (1) which is used here for the analysis. Comments. Some Mesozoic taxa of Chrysopidae appear to posses state (1) (see e.g. Figure 2G in [37]). However, this is likely a derived condition within the family as ScP reaches the pterostigmal region in the vast majority of the other taxa (including Mesozoic forms). Comments. Nevrorthidae, Osmylidae, Nymphidae and Berothidae are polymorphic for this character. The subcostal veinlets in some species of Nevrorthidae are mostly forked (e.g., some Nipponeurorthus Nakahara; one undescribed species from Baltic amber), whereas in others they are mostly simple; state (0) is used for the analysis. State (1) is used for the analysis in Osmylidae, although some subcostal veinlets in many genera are forked. In some Nymphidae (e.g. Myiodactylus Brauer: [38]) the majority of subcostal veinlets are forked. In some Berothidae (e.g., the Burmese amber genera: Figures 19,24,25 in [39]) all subcostal veinlets are simple.
Comments. Coniopterygidae and Kalligrammatidae are polymorphic for this character. In Coniopterygidae, all three states appear occur if assumed that MA is reduced. State (1) is used for the analysis as it is characteristic of the most genera of Aleuropteryginae, a more ancient subfamily and more diverse in the fossil record than Coniopteryginae (see Table 1 in [56]). Most genera of Kalligrammatidae have a pectinate branched MP with branches anteriorly directed, clearly a derived condition within the family; state (0) is characteristic of Protokalligramma Yang et al. and an undescribed genus from Karatau [40] and is used for the analysis. In Sialidae, state (0) is used for the analysis, but some species have the simple MP.  [57] for this vein in the forewing of a basal blattinopsidaean from Carboniferous). In Neuroptera, this vein is well developed in the Permian Permithonidae (see Figures 2,3,6 in [58]) and Mesozoic Mesithoninae (Berothidae) (see Figures 1,2 in [59]). The families Ithonidae and Osmylidae are polymorphic for this character. The m-cu arculus is not discernible from crossveins in most Osmylidae, but distinct in some Jurassic taxa (e.g. Archaeosmylidia Makarkin et al., and an undescribed genus from Daohugou [36], VM, QY, pers. obs.), especially in the latter taxon. The same situation is in Ithonidae where the m-cu arculus is distinct in some genera (e.g., Platystoechotes Carpenter), and not discernible from crossveins in the others (e.g., Rapisma Walker), see Figure 2 in [54].
Comments. The partial fusion of M and CuA occurring in all Raphidioptera (including Priscaenigmatidae) and Sialidae probably evolved independently. Comments. The fusion of MP and CuA in the forewing is a synapomorphy of Myrmeleontoidea (but it is unclear concerning Babinskaiidae due to small examined specimens). The similar character state found in some genera of other families (e.g., some Nallachius among Dilaridae: Figure 1 in [60]) undoubtedly evolved independently. Comments. Berothidae, Dilaridae, Grammolingiidae, Kalligrammatidae and Mantispidae are polymorphic for this character. Some genera or species of Berothidae, Mantispidae Mantispidae and Dilaridae have CuA not pectinate (dichotomous or so). In the most genera of Kalligrammatidae, CuA is usually weakly pectinate; state (0) characteristic of Protokalligramma and an undescribed genus from Karatau [40] is used for the analysis. The pectinate branches of the Grammolingiidae species are long and dichotomously branched. Comments. Kalligrammatidae, Mantispidae, Nymphidae and Psychopsidae are polymorphic for this character. In the most genera of Kalligrammatidae, CuA is usually weakly or strongly pectinate; state (1) is characteristic of Protokalligramma and an undescribed genus from Karatau [40] is used for the analysis. Some taxa of Mantispidae have CuP dichotomously branched (e.g., Mesomantispa Makarkin) or with terminal fork (e.g., some Symphrasinae). In some species of Nymphidae, CuP is only weakly pectinate. Some genera of Psychopsidae have CuP to be strongly dichotomously branched (e.g., Undulopsychopsis: Figures 2 in [33]; Baisopsychops: Figure 1 in [34]). Comments. Berothidae, Ithonidae, Kalligrammatidae and Nymphidae are polymorphic for this character. In some genera or species of Berothidae and Ithonidae, AP1+2 is pectinate. Most species of Kalligrammatidae have AA3+4 more or less pectinate; state (1) characteristic of Protokalligramma and an undescribed genus from Karatau [40] is used for the analysis. In the genera of Myiodactylinae, AA3+4 is pectinate, in the other genera of Nymphidae it is deeply or shallowly forked; state (1) is used for the analysis.
Comments. Kalligrammatidae and Sisyridae are polymorphic for this character. In some genera of Kalligrammatidae (e.g., Sophogramma Ren et Guo), the AP1+2 is deeply forked, not pectinate. In Sisyridae, this vein is few-pectinate or has terminal fork; state (2) is used in the analysis. Comments. The full reduction of the anal lobe occurs probably only in families of the myrmeleontoid clade (except Chrysopidae). However, it evolved also independently within some other families in advanced genera (e.g., in Coniopterygidae, Berothidae). Comments. Neuroptera normally bear well-developed hind wings more or less similar in size to forewing, but there are a few brachypterous, micropterous or apterous species, found in the following extant families: Hemerobiidae, Coniopterygidae, Ithonidae, Dilaridae, Berothidae, and Nemopteridae [63,64]. Such reduction is usually associated with flightlessness, and obviously derived within genera or generic groups. The highly modified hind wings of Nemopteridae are an autapomorphy of this family.
Comments. The humeral veinlet of Psychopsidae is recurrent but not branched; state (1) is used for the analysis. Comments. Berothidae and Mantispidae are polymorphic for this character. The basal r-m brace is long and sinuate in Mesithoninae and Rhachiberothinae among Berothidae, and Symphrasinae among Mantispidae, whereas in other taxa of these families it is straight, crossvein-like. State (0) is used for analysis.
Comments. Mantispidae is polymorphic for this character; the complete CuP is present only in Symphrasinae, and strongly reduced in others. CuP of Berothidae varies in its appearance in different genera from the reduction of its middle part (basal and distal parts are present) to entire loss.