A new genus and species of Collyriinae (Hymenoptera, Ichneumonidae)

An enigmatic taxon collected in China is described as Bicurta sinica gen. n., sp. n. The unique specimen proved difficult to place to subfamily but has features in common with Collyria, until recently the sole valid genus of the small Palaearctic subfamily, Collyriinae. A morphological phylogenetic analysis of the pimpliformes group of subfamilies confirms the placement of this genus in the Collyriinae, which is here redefined.


Introduction
The speciose family Ichneumonidae is currently divided into about 38 subfamilies (Quicke et al. 2009), although some groupings are treated differently by different authors (see, for example, the website of the American Entomological Institute: http:// www.amentinst.org/).This large number of subfamilies has been divided into a num-ber of subfamily groupings, largely by the pioneering work of Wahl (1986Wahl ( , 1990Wahl ( , 1991) ) and Gauld (1985), with the details refined by Quicke et al. (2009).Although we are working towards a relatively stable higher classification of the Ichneumonidae, there are many areas of uncertainty, such as the classification of the various Ctenopelmatinae tribes in relation to several other subfamilies (Gauld and Wahl 2006;Quicke et al. 2009).Another area of difficulty is the pimpliformes group of subfamilies.Relationships within this clade (see Wahl 1986Wahl , 1990;;Wahl and Gauld 1998;Quicke et al. 2009) have proved difficult to reconstruct, partly because of missing biological and larval information for some enigmatic taxa and partly because the 28S D2 ribosomal RNA data do not provide much support for subfamily or tribal relationships in this area.It can be inferred that the pimpliformes underwent a rapid radiation which has resulted in few discrete morphological apomorphies and the recognition of various very small groups of species as discrete subfamilies.One such subfamily is Collyriinae, comprising only one genus, Collyria Schiødte, until recently.After this paper was accepted for publication, Kuslitzky and Kasparyan (2011) described a second genus of Collyriinae, Aubertiella Kuslitzky and Kasparyan, 2011, which we have not been able to include in the phylogenetic analyses here.Although excluded from the pimpliformes by Gauld (1997) and Wahl and Gauld (1998), Collyria shows some clear pimpliform apomorphies, such as the basally elongated propodeum, and clearly grouped with the pimpliformes in Quicke et al. 's (2009) combined morphological and molecular phylogenetic analyses.As the Collyriinae is a subfamily now containing only two genera, defined by some unusual character states within the Ichneumonidae, the current diagnosis of the subfamily was, until Kuslitzky and Kasparyan (2011), the diagnosis of the original genus, Collyria, and now requires reassessment with the addition of more plesiomorphic genera.
Two of the authors (M-LS and S-PS) received a single specimen of a distinctive ichneumonid collected in Jiangxi province, P.R. China.Unfortunately, further fieldwork by M-LS and S-PS in the type locality has failed to uncover any further specimens.This specimen proved very difficult to place in any subfamily, with a combination of character states that could almost equally feasibly place it in Poemeniinae or Collyriinae.For example, both subfamilies have an elongate propodeum with the spiracle only a little anterior to the middle; they both often lack transverse carinae on the propodeum; the hind coxa is elongate; the first metasomal segment is usually of a similar, elongate shape; the first abscissa of hind wing vein cu is much shorter than vein cu-a.This specimen, which obviously represents an undescribed species and genus, lacks the apomorphies of Collyria, namely the decurved ovipositor with small serrations along the lower margin and the distinctive claw characters (fore and mid tarsal claws each with a median tooth), although it does have lobate fore and mid claws, in common with several pimpliform taxa.The new specimen lacks the principle apomorphies of the Poemeniinae, namely the ventral continuation of the epomia parallel to the lower margin of the pronotum and the laterally expanded foramen magnum (although this is difficult to see in the single new specimen).As well as the character states that are common to Poemeniinae and Collyria, the new specimen shows three characters of the head that led us to believe that its affinities are closer to Collyria, namely the short antennae, the presence of a bifurcate carina from the dorsal half of the face to between the antennae, and a weak median tubercle on the clypeus.After much deliberation, we hypothesised that this specimen represents a new genus of Collyriinae.To test this hypothesis, we coded the specimen of Bicurta sinica sp.n. and Collyria coxator (Villers) for Wahl and Gauld's (1998) morphological characters, to establish the position of these genera within the pimpliformes.

Materials and methods
For the phylogenetic analyses, codings were based on the matrix of Wahl and Gauld (1998) and on specimens in the Natural History Museum, London and in the Insect Museum, General Station of Forest Pest Management (GSFPM), State Forestry Administration, People's Republic of China (the holotype of Bicurta sinica sp.n.).
The character codings for Bicurta gen.n. and Collyria are shown in Table 1 with the character numbers as in Wahl and Gauld (1998).Given that these genera share some distinctive characters that were not included in Wahl and Gauld's analysis, two additional characters were included in our matrix.
Phylogenetic analyses were carried out in TNT 1.1 (Goloboff et al. 2003), with all characters unordered and using default settings except for the following (as employed by Burks et al. 2011): ratchet weighting probability (up and down) of 5%, 200 iterations, drift of 50 cycles, tree fusing of five rounds, and find minimum length 25 times.Phylogenetic trees were edited in Winclada (Nixon 1999).
SEM images of uncoated specimens were taken using a Leo 1455VP low vacuum scanning electron microscope.Photographs of Bicurta sinica sp.n. were taken using a Canon Power Shot A650 IS and Cool Snap 3CCD attached to a Zeiss Discovery V8 Stereomicroscope and captured with QCapture Pro version 5.1.

Phylogenetic analyses
With characters unordered and unweighted, 12 trees of length 240 were found; the strict consensus is shown in Fig. 1.The relationships betweeen subfamilies are largely unresolved but Bicurta and Collyria are recovered as a clade, as are all other subfamilies with multiple representatives, except Cylloceriinae.Searching with implied weights of values ranging from k=1 to k=10 resulted in a single topology, shown in Fig. 2.This phylogeny is similar to that obtained by Wahl and Gauld (1998), except that Xoridinae shift to the sister group of the labeniformes plus ichneumoniformes and the genera of Poemeniinae are fully resolved.Bicurta+Collyria are recovered as a clade and as the sister group to Rhyssinae.As a test of the robustness of the results, characters 72 to 93 (which include both those characters missing for a large number of taxa and the two additional characters included in this study) were excluded and the analysis run using the same parameters.The topology of Collyriinae, Rhyssinae and Poemeniinae remained the same, although relationships within the remaining pimpliformes collapsed in the strict consensus (Fig. 3).
In these analyses, the monophyly of Collyriinae is attested by numerous homoplasies and two synapomorphies: the presence of a bifurcate carina on the upper face extending to between the antennal sockets and the short antennae.The sister group relationship of Collyriinae to Rhyssinae was unexpected and is supported by a single apomorphy, the absence of the posterior transverse carina of the propodeum.The monophyly of Poemeniinae+Rhyssinae+Collyriinae is again weakly supported by one unambiguous apomorphy (the small and subrectangular clypeus) and two homoplasies (hind wing vein 2/Cu originating close to vein M and the elongate last visible tergite of the female).In contrast, Quicke et al. (2009), in their combined morphological and molecular analyses, found Collyria to nest within the Diptera-parasitizing clade of pimpliformes, in a topology that seemed to be overwhelmingly influenced by the morphology dataset.

Definition of Collyriinae
The Collyriinae, now comprising the genera Aubertiella, Bicurta gen.n. and Collyria, can be defined by the following characters, based on the phylogenetic analyses presented here and on the description of Aubertiella (Kuslitzky and Kasparyan 2011), although only the first two are autapomorphic for the subfamily: dorsal part of face with bifurcate carina extending between antennal sockets (character not mentioned   not ridges across the depth of the apical part of the lower valve).The monophyly of Bicurta is supported by some rather weak characters, including the pale markings on the face and malar space; the more posteriorly displaced propodeal spiracle (compared to Collyria); the large, lobe-like teeth on the fore and mid tarsal claws (which may be plesiomorphic with respect to the narrower teeth of Collyria); fore wing vein 2m-cu with one bulla; the first tergite and sternite fused; and the first sternite more than half the length of the tergite.
An expanded phylogenetic matrix, encompassing the genera of Acaenitinae, could reveal some rather different patterns of relationships within the pimpliformes.Several acaenitine genera share character states with collyriines and some poemeniines, such as short antennae, a median tubercle on the clypeus, hind wing vein Cu1 originating close to M and the propodeum lacking transverse carinae.However, acaenitines have a distinctive apomorphic female hypopygium, very different to that of the Collyriinae, Poemeniinae or Rhyssinae.

taxonomy
Collyriinae Cushman http://species-id.net/wiki/CollyriinaeDiagnosis.Collyriinae can be distinguished from all other subfamilies of Ichneumonidae by the following combination of characters: 1) dorsal part of face with a bifurcate carina extending between the antennal sockets and 2) antenna short, only slightly longer than combined length of head and mesosoma, 0.65-0.7×length of fore wing.Additional distinctive characters, in combination (individually, all are shared with other taxa) are the elongate propodeum with strong lateromedian longitudinal carinae, very stout hind femur, elongate hind coxa and the subclavate shape of the metasoma.
As the concept of Collyriinae has now been expanded since Townes's (1971) definition, we provide a modified description of the subfamily below.
Description.Antenna short, c. 0.65-0.7×length of fore wing.Male flagellum without tyloids.Mesosoma subcylindric.Occipital carina complete, evenly arched dorsally.Ventrally reaching hypostomal carina well behind base of mandible.Dorsal part of face with a bifurcate carina extending between antennal sockets.Clypeal suture vestigial between clypeal foveae, clypeus faintly convex, apical margin with median tooth or protruberance.Basal portion of mandible wider, strongly narrowed toward apex, teeth sharp, teeth subequal or lower tooth longer than upper tooth.Maxillary palpus with 5 segments, labial palpus with 4 segments.Foramen magnum not expanded laterally.Anterior slope of mid lobe of mesoscutum approximately vertical.Epomia absent.Notaulus long.Epicnemial carina present.Postpectal carina incomplete.Propodeum long, rather cylindrical, longitudinal carinae developed to varying degrees, transverse carinae absent, juxtacoxal carina absent, propodeal spiracle oval.Apex of fore tibia without a tooth on outer side.Fore and hind tibiae each with two spurs.Fore and mid tarsal claws each with either tooth at mid-length or basal lobe, hind tarsal claw large, simple, strongly curved.Hind femur stout, 3.0-3.6×as long as maximally deep.Metasoma subclavate, weakly laterally compressed in distal half.First metasomal segment long, narrow, spiracles anterior to middle, sclerotized part of first sternum extending to middle of tergite or anterior to this.Last visible tergite usually elongate.Hypopygium not elongate.Ovipositor slightly to markedly decurved.Fore wing vein 1cu-a opposite 1/M, vein 3rs-m absent.Hind wing with abscissa of Cu between M+Cu and cu-a strongly reclivous, about 0.2× as long as cu-a.
Biology.Collyria coxator (Villers) is a common parasitoid of Cephus pygmaeus (Linnaeus) (Hymenoptera: Cephidae) in Europe and a detailed account of its life history was published by Salt (1931).Another species of Collyria, C. catoptron Wahl, has been reared from Cephus fumipennis Eversmann (Wahl et al. 2007).Little is known about the biology of other species but they are likely to all be parasitoids of Cephidae.The biology of the genus is unusual for Ichneumonidae in that oviposition is into the host egg with emergence from the fully grown host larva after it has spun its cocoon (Salt 1931).Nothing is known of the biology of Bicurta sinica sp.n. or of Aubertiella nigricator (Aubert 1964).
Geographic range.The nine described Collyria species are found across the Palaearctic, although with few published records from the Eastern Palaearctic (Yu et al. 2009).Collyria coxator was introduced to Canada (Saskatchewan) (Smith 1931) in an unsuccessful (Carlson 1979) attempt to control the native Cephus cinctus Norton.However, it does seem to have become established in North America as a parasitoid of the introduced Cephus pygmaeus (Filipy et al. 1985).Aubertiella nigricator is known from Israel and Syria (Kuslitzky and Kasparyan 2011).
Diagnosis.Bicurta can be distinguished from Collyria by any of the following characters (state in Collyria in brackets: 1) epicnemial carina not clearly visible dorsal to mesosternum (carina distinct on mesopleuron); 2) ovipositor straight and smooth, without teeth on ventral valve (weakly decurved with weak teeth on ventral valve in most species; 3) fore and mid tarsal claws with acutely lobed tooth (with a weak medial tooth).Aubertiella resembles Bicurta in the very weak clypeal tubercle and simple ovi-positor but can be distinguished by the median teeth on the fore and mid tarsal claws (similar to Collyria), black face and the apical tergites retracted beneath the sixth tergite.
Description.Clypeus nearly flat in lateral view, about 2.2 × as wide as high in anterior view (Fig. 10), median section of apical margin almost truncate, with an obtuse median tubercle or angulation.Mandible strongly narrowed toward apex, teeth sharp, lower tooth slightly longer than upper tooth.Dorsal part of face with bifurcate carina that extends between antennal sockets (Fig. 6a).Antenna short, 0.66x fore wing length, almost clubbed.Notaulus deep, reaching to middle of mesoscutum level with posterior margin of tegula (Fig. 11b).Epicnemial carina indistinct, not clearly visible dorsal to mesosternum (Fig. 11a) although slight furrow can be traced dorsally, far posterior to front edge of mesopleuron.Sternaulus vestigial on anterior 0.4 of mesopleuron.Scutellum and postscutellum approximately flat.Anterior section of submetapleural carina vestigial.Areolet absent.Fore wing with vein 1cu-a opposite 1/M; 2m-cu slightly inclivous, with one bulla.Hind wing with abscissa of Cu between M+Cu and cu-a much longer than cu-a (Cu1 originating close to vein M). Fore and mid tarsal claws elongate with acutely lobed tooth (Fig. 8a).Hind tarsal claw simple (Fig. 8b).Hind coxa elongate, almost as long as first tergite.Hind femur stout, 3.3x as long as maximally deep.Hind leg particularly long, in total 1.9x length of fore wing.Hind coxa elongate, about 0.8 × as long as hind femur, Propodeum elongate, with complete longitudinal carinae, median longitudinal carinae slightly convergent posteriorly, without transverse carinae (Fig. 5a).Propodeal spiracle obliquely elliptical, located at about mid-length of propodeum.Basal portion of metasoma narrow and elongate, apical portion laterally compressed.First tergum approximately 5 × as long as apical width, without longitudinal carinae; sternum reaching half length of tergum, fused with tergum; without glymma; spiracle located at basal 0.42.Ovipositor smooth, without teeth on ventral valve (Fig. 9).Otherwise as in the description of the subfamily.
Etymology.The name of the new genus is based on the short antenna and ovipositor sheath.The gender is feminine.Head.Face approximately flat, 1.4 × as wide as long, with even punctures, distance between punctures 0.2 to 1.0 × diameter of puncture, lateral sides (inner orbit) impunctate and with fine granular texture.Clypeus nearly flat, about 2.2 × as wide as long, with fine, sparse punctures, distance between punctures 2 to 4 × diameter of puncture, apical portion smooth, impunctate.Labrum crescentic, about 0.33 × as long as wide.Malar space with fine leathery texture, without subocular sulcus, approximately 0.4 × as long as basal width of mandible.Gena glossy, with distinct fine punctures, in lateral view approximately 0.66 × as long as width of eye, evenly convergent backward.Posterior portion of vertex with fine punctures, portion between lateral ocellus and eye with fine leathery texture.Interocellar area slightly convex, with fine longitudinal wrinkles.Postero-ocellar line approximately as long as ocular-ocellar line.Dorsolateral part of frons with fine punctures, distance between punctures about as long as diameter of puncture; median portion narrowly smooth longitudinally; ventral portion with weak median longitudinal carina reaching to median protuberance of face.Antenna 5 mm, with 20 flagellomeres, ratio of length of flagellomere 1:2:3:4:5 is 5.5:4.0:3.8:3.7:3.4; last flagellomere 3 × as long as wide, approximately as long as fourth flagellomere.Distance from hypostomal carina to mandible about as long as basal width of mandible.

Bicurta sinica
Mesosoma.Anterior portion of pronotum with fine longitudinal wrinkles; dorsal portion slightly scabrous; near dorsomedian portion with transverse wrinkles, posterior sections of the wrinkles parallel dorsal margin of pronotum; ventral portion with dense transverse wrinkles.Epomia indistinctly differentiated from strong oblique wrinkles.Mesoscutum with fine punctures; punctures on middle lobe denser than on lateral lobe, distance between punctures 0.2 to 2.5 × diameter of puncture; distance between punctures on lateral lobe 0.5 to 3.5 × diameter of puncture; posterior median portion with longitudinal concave and transverse wrinkles.Scutellum with dense punctures, distance between punctures 0.2 to 0.5 × diameter of puncture.Postscutellum with rela- tively large, elongate punctures.Lower portion of mesopleuron slightly scabrous, with dense punctures; dorsoanterior portion, in front of subalar prominence, with short longitudinal wrinkles; median portion (anterior to speculum) and ventroposterior por-  tion with short transverse wrinkles.Speculum relatively large.Mesosternum densely punctate.Median longitudinal suture of mesosternum distinct, slightly widening posteriorly.Metapleuron scabrous, with irregular, elongate punctures.Metasternum elongate, approximately 0.6 × as long as mesosternum, with distinct median longitudinal carina and irregular transverse wrinkles.Wing hyaline with slight grey tinge.2rs-m basad 2m-cu by 0.66 × length of 2rs-m.Vein 2-Cu as long as 2cu-a.Hind coxa with distinct punctures.Ratio of length of hind tarsomeres 1:2:3:4:5 is 10.0:4.2:2.9:2.0:4.2.Propodeum between carinae with distinct transverse wrinkles.Propodeal spiracle 1.4 × as long as maximum width, distance to pleural carina approximately 2.6 × as long as distance to lateral longitudinal carina.
Metasoma.First tergum approximately 5 × as long as apical width, with longitudinal wrinkles, between wrinkles with punctures; without longitudinal carina; spiracle convex, located at basal 0.42.Second tergum about 2.0 × as long as apical width, slightly widened posteriorly, with sparse, indistinct punctures.Third tergum with even,     fine hairs, gradually weaker and indistinct posteriorly.Ovipositor sheath about 0.27 × as long as hind tibia.Ovipositor very slightly compressed.
Colour.Black.Ventral, inner orbits, clypeus, stripe passing through anterior tentorial pits, mandible except teeth, yellow; ventral profile of antenna brown to yellowish brown.Labial and maxillary palpi, fore and mid legs, trochantellus of hind leg, hind tarsomeres buff.Apex of hind coxa, ventral profile of trochanter of hind leg, basal and apical portion of hind femur brown.Basal 0.65 of hind tibia dull yellow, fading to dark brown apical 0.35.Tegula dark brown.Hind margins of terga 3 to 6 narrowly yellow.Wing venation, including pterostigma dark brown.
Etymology.Named after the country, China, where the unique specimen was collected.
Diagnosis.A distinctive species with the short, featureless ovipositor, rather massive hind leg, lobate fore and mid claws, short antennae and well-marked facial pattern.

Discussion
Unfortunately, nothing is known of the biology of Bicurta sinica sp.n.Where known, species of Collyria are koinobiont egg-larval endoparasitoids of stem-sawflies (Hymenoptera: Cephidae) (Salt 1931;Wahl et al. 2007).This is an unusual strategy within Ichneumonidae and presumably accounts for the distinctive ovipositor of Collyria; slender, lacking apical teeth or a notch but with serrations on the lower valves for cutting through grass stems.The slender, featureless ovipositor of Bicurta could well be indicative of oviposition into insect eggs, but this must remain as speculation for now.
An expanded phylogenetic matrix, encompassing the genera of Acaenitinae, could reveal some rather different patterns of relationships within the pimpliformes.Several acaenitine genera share character states with collyriines and some poemeniines, such as short antennae, a median tubercle on the clypeus, hind wing vein Cu1 originating close to M and the propodeum lacking transverse carinae, and it is interesting that various older authors included Collyria within the Acaenitinae (or equivalent grouping).Obviously, acaenitines have a distinctively apomorphic female hypopygium, very different to that of the Collyriinae, Poemeniinae or Rhyssinae.

Figure 1 .
Figure 1.Cladogram of selected pimpliformes taxa.Strict consensus of 12 trees of length 240.Apomorphic characters are indicated by black squares, homoplasies by white squares.

Figure 3 .
Figure 3. Strict consensus of 89 trees resulting from analysis of reduced data matrix (characters 72-93 excluded).

Figure 7 .
Figure 7. First tergite a and pronotum b of Bicurta sinica.

Figure 8 .
Figure 8. Fore claw a and hind claw b of Bicurta sinica.

82 83 84 85 86 87 88 89 90 91 92 93
Yoder et al. 2010).URIs are provided in Table2.Note that, at the time of writing, wing vein nomenclature and several other morphological terms used here have not yet been included in the HAO.

table 2 .
Morphological characters and URIs to concepts in the Hymenoptera Anatomy Ontology.