A review of the South American genera of Cimbicidae (Insecta, Hymenoptera)

. The South American genera of the Cimbicidae are reviewed. Five genera and nine species are recognized. Redescriptions of all genera and an identification key to all species are provided. All species are illustrated, including both sexes and aberrant specimens when relevant. The South American Cimbicidae are grouped in the subfamily Pachylostictinae, but there is substantial morphological divergence at the genus level. This and the isolated geographic and phylogenetic position relative to the other subfamilies of Cimbicidae indicates that the Pachylostictinae have evolved in isolation for a substantial amount of time. Host plant records are known for only one species, Pseudopachylosticta subflavata , which is mainly found in the Chacoan subregion. The distribution of the remaining species falls almost exclusively within the range of the Parana subregion forest provinces, a biome that has been much reduced by human activity in the past half millennium. It is likely that these rarely collected wasps are threatened by habitat degradation. sulcus deep notauli laterophragmal apodeme postscutellum absent. Small anterodorsal part of mesopleuron separated from rest by vertical groove prepectus absent as separate sclerite. Horizontal carina absent laterally on mesopleuron. Posterior thoracic spiracle visible in lateral view, situated in incurvation in dorsal margin of mesopleuron. Median midcoxal articulations adjacent, only separated by small wedge of cuticle. Mesofurca not observed. Insertion of mesonoto-metanotal muscle on small projection on anterior margin of metanotum; cenchri approx. 2× as broad as long. Anapleural cleft present, small. Metapleuron fused with abdominal tergum 1 along dorsal margin; posteroventral metapleural apodeme not observed; paracoxal sulcus curving posteriorly, terminating in the middle of the metapleural sulcus; metacoxal foramina open dorsally, without metapleural inflection laterally. Metafurca not observed. Hind coxa less than twice as long as wide, median carina or spine not observed. Hind femoral ventral spur absent. Hind tibial apical spurs shorter than apical width of tibia. Hind basitarsomere shorter than tarsomeres 2–4, tarsal claws bifid, teeth of subequal length. ings

Color. Coloration predominantly black to dark brown (Fig. 5), creamy white markings of various size on all body parts (e.g., clypeus on head (Fig. 5B), lateral parts of pronotum). Legs creamy white proximally, black to dark brown distally. Wings predominantly hyaline.
[from Smith 1988]. Labrum broad, convex, flat, hairy, distal margin evenly curved. Mandibles less than ½ the height of head, with three teeth each (Fig. 5B), inner margin not serrated. Maxilla with stipes of approx. equal width throughout, palps with six palpomeres, longer than labial palps. Labial palps with four palpomeres, palps inserting at level with maxillary palps. Postmentum narrow, at least 3× as long as wide. tHorax. Pronotum comparatively high medially, with transverse grove ending in small depression laterally, no lateral groove; pronotum articulating with mesopleuron for short distance ventrolaterally. Dorsal cervical sclerite present. Propectus without lateral projection, propleural sulcus present, medioventral margins of propectus widely separated, posteriorly extended into narrow points. Prosternum laterally extended, continuous with katepisternum which articulate, but does not fuse with propleuron at lateral coxal articulation point. Anterior fore tibial spur straight, simple, not much longer than posterior spur, spurs pointed and sclerotized apically. Mesonotum with distinct median sulcus and deep notauli (Fig. 5C), laterophragmal apodeme not observed, postscutellum absent. Small anterodorsal part of mesopleuron separated from rest by vertical groove (Fig. 5A), prepectus absent as separate sclerite. Horizontal carina absent laterally on mesopleuron. Posterior thoracic spiracle visible in lateral view, situated in incurvation in dorsal margin of mesopleuron. Median midcoxal articulations adjacent, only separated by small wedge of cuticle. Mesofurca not observed. Insertion of mesonoto-metanotal muscle on metanotum not observed; cenchri approx. 2× as broad as long. Anapleural cleft present, small. Metapleuron fused with abdominal tergum 1 along dorsal margin; posteroventral metapleural apodeme not observed; paracoxal sulcus curving posteriorly, terminating in the middle of the metapleural sulcus; metacoxal foramina open dorsally, without metapleural inflection laterally. Metafurca not observed. Hind coxa less than 2× as long as wide, median carina or spine not observed. Hind femoral ventral spur absent. Hind tibial apical spurs not much longer than apical width of tibia. Hind basitarsomere slightly longer than tarsomeres 2-4, tarsal claws bifid, teeth of subequal length.
Wings. Fore wing with vein M joining Sc+R close to Rs+M; vein 2r-m posteriorly inserts on cell 2M, very close to anterior end of 2m-cu; vein 1m-cu oriented obliquely, inserting on M some distance from 2r-m (distance 1m-cu-2r-m at least ½ distance Rs+M-1m-cu on M); posterior anal vein present proximally and distally but discontinuous in the middle. Hind wing cell R1 closed; vein M continuous, separating cells Rs and M, cell M not reaching vein Rs; cross vein 2a absent.

Comments
According to Smith (1988), the holotype was collected in Ypiranga (possibly Ipiranga, São Paulo, Brazil). The other material examined here fits well with the original description of Conde (1932). Conde originally described the species as Pseudabia clypealba, but later transferred it to a separate genus, Brasilabia (Conde 1937); the justification for removing the species from Pseudabia was the medially subdivided abdominal tergum 1 and the small size. The tergum 1 configuration is indeed unique among all Cimbicidae; it might represent a retained plesiomorphy (Blasticotomidae, Diprionidae, most Tenthredinidae and some Argidae and Pergidae display this feature; see Vilhelmsen 2015: character 80) or a reversal compared to other cimbicids. Also diagnostic of Brasilabia clypealba is the eponymous creamy-white clypeus, contrasting with the blackish-brown color of the remainder of the head capsule; all other South American cimbicids have the head capsule uniformly darkly colored in anterior view.

Material examined
BRAZIL: -Rio MeasureMents. Small to medium-sized sawflies, body length 6 to 9 mm, male smaller than female.
Color. Body coloration predominantly dark brown to black (Figs 6-7). Underside of abdomen creamy white except for apex, white parts extending onto lateral part of terga to va rious extent. Antennae and mouth parts dark brown; coxae and trochanters variable, femora and tarsi predominantly dark brown to black, tibiae creamy white. Wings hyaline, venation dark brown.
tHorax. Pronotum comparatively high medially, with transverse groove extending close to dorsolateral corner, no lateral groove; pronotum fused with mesopleuron for some distance ventrolaterally. Dorsal cervical sclerite present. Propectus without lateral projection, propleural sulcus present, medioventral margins of propectus widely separated, posteriorly extended into narrow points. Prosternum laterally extended, continuous with katepisternum which articulate, but does not fuse with propleuron at lateral coxal articulation point. Anterior fore tibial spur straight, simple, not much longer than posterior spur, spurs pointed and sclerotized apically. Mesonotum with median sulcus indistinct, marked as line rather than groove, notauli well developed as grooves (Fig. 6C), laterophragmal apodeme not observed, postscutellum absent. Small anterodorsal part of mesopleuron separated from rest by vertical groove, prepectus absent as separate sclerite. Horizontal carina absent laterally on mesopleuron. Posterior thoracic spiracle covered in lateral view by posterodorsal margin of mesopleuron, short spine projects dorsally just posterior to spiracle (Fig. 7D). Median midcoxal articulations adjacent, only separated by small wedge of cuticle. Mesofurca not observed. Insertion of mesonoto-metanotal muscle on metanotum simple, not on conspicuous structure; cenchri oval, less than 1.5× as broad as long. Anapleural cleft present, small. Metapleuron fused with abdominal tergum 1 along dorsal margin, line of fusion dark; posteroventral metapleural apodeme not observed; paracoxal sulcus curving posteriorly, terminating in the middle of the metapleural sulcus; metacoxal foramina open dorsally, without metapleural inflection laterally. Metafurca not observed. Hind coxa less than twice as long as wide, median carina or spine not observed. Hind femoral ventral spur absent. Hind tibial apical spurs not much longer than apical width of tibia. Hind basitarsomere at least 1.5× as long as than tarsomeres 2-4, tarsal claws bifid, teeth of subequal length.
Wings. Fore wing with vein M joining Sc+R close to Rs+M; in females vein 2m-cu elongate and extends obliquely with anterior end terminating in vein Rs+M proximally to vein 2r-m ( Fig. 6D), in males vein 2m-cu is short and anteriorly inserts in vein M well distal to vein 2r-m; vein 1m-cu oriented obliquely, inserting on Rs+M some distance from 2r-m (distance 1m-cu -2r-m at least ⅓ distance M -1m-cu on Rs+M); posterior anal vein present proximally and distally but discontinuous in the middle.

Comments
Originally described as Lopesia thomasi by Conde (1937). According to Conde, the holotype was collected in the Jardin Botanico in Rio de Janeiro in February 1936 and placed in the custody of 'Frey Thomas' (perhaps a monk, i.e., Friar Thomas; the species is named after him). We have not been able to examine the type; the material examined here fits well with the original description. Smith (1988) created the replacement name Lopesiana, as Lopesia Conde, 1937 is a homonym of Lopesia Rübsaamen, 1908 (Diptera, Cecidomyiidae).
Lopesiana thomasi with a body length between 6 and 9 mm is the smallest of the South American Cimbicidae. Its upper size range overlaps with that of Brasilabia and Pseudopachylosticta. Among Cimbicidae in general, only the Palaearctic genus Corynis has members which are as small as Lopesiana.
Apart from the small size, Lopesiana can be separated from the other South American cimbicids by a combination of characters: having non-metallic body coloration, the antenna inserted very low on the face and with the dorsomedian margin of the toruli forming a distinct carina above the antennal bases, the posterior thoracic spiracle being concealed in lateral view (shared with Corynis), having a short, triangular 1st ovipositor valve (compare fig. 48 with figs 42-47 in Smith 1988). The anterior insertion of fore wing vein 2m-cu on vein Rs+M female Lopesiana is unique within South American Cimbicidae; the insertion of 2m-cu proximal to the posterior end of vein 2r-m resembles the condition in Abiinae and Cimbicinae (see Fig. 2B), that of the males the condition which is observed in other Cimbicidae, including the South American taxa.

Redescription (female, male structures only mentioned when differing from females).
MeasureMents. Comparatively large and robust sawflies, body length 12-16 mm.
Color. Males (Figs 9, 12) with dark blue metallic coloration on most of body, rarely with parts of thorax ( Fig. 12B) or abdominal tergum 4 to 6 reddish brown (Fig. 12D). Females (Figs 8, 10-11) with extensive reddish-brown coloration on large parts of thorax and also often anterior abdomen, remaining body parts dark blue metallic. Wings mostly darkly infuscated in both sexes, in female P. apicalis infuscation distally contrast with more hyaline wing coloration proximally (Fig. 10A).
Head. Eyes at most slightly converging ventrally, inner margins at most slightly incurved. Posterior ocelli at level with dorsal margin of eyes (Figs 8B, 10B, 11B). Toruli in middle of face, approx. halfway between median ocellus and ventral margin of clypeus. Epistomal sulcus absent. Clypeus with ventral margin straight. Gena medially less wide than width of eye, wider dorsally than ventrally. Malar space very low. Occipital carina absent. Sclerotisation between occipital and oral foramina present. Antennae with five antennomeres; antennomere 1 approx. 2× as long as wide, antennomere 2 approx. as wide as long, antennomere 3 1.2-1.5× as long as antennomere 4, antennomere 5 slightly expanded distally; females of P. albiventris and P. apicalis with elongate, lighter colored area on ventral side of antennomere 5. Labrum broad, convex, hairy, raised in the middle under ventral margin of clypeus, distal margin straight or slightly curved. Mandibles less than ½ the height of head in both sexes, with three well developed teeth on right, proximal tooth less developed on left mandible, inner margin not serrated. Maxilla with stipes of approx. equal width throughout, palps with four palpomeres, shorter than labial palps. Labial palps with three palpomeres, palps inserting at level with maxillary palps. Postmentum narrow, at least 3× as long as wide.

Comments
Pachylosticta Klug, 1824 is the first genus of South American Cimbicidae described and hence the nominal genus of the Pachylostictinae. The most striking feature of the genus is the thickened and anteriorly extended pterostigma in the males. The absence of this feature in the females resulted in the genus Plagiocera Klug, 1834 being proposed for Plagiocera thoracica; judging from the illustration in Klug (1834: plate II, fig. 5) the description was based on what appears to be a female of Pachylosticta albiventris. Only much later was the connection between the two genera made; the earliest reference to Plagiocera as a synonym of Pachylosticta we have come across is in Konow (1907). An autapomorphy for the genus displayed by both sexes is the orientation of fore wing vein 1m-cu, which inserts on vein Rs+M distally, so that the distance between the insertions of 2r-m and 1m-cu on Rs+M is at most ¼ of the distance between the insertions of M and 1m-cu on Rs+M.
Pachylosticta is most similar to Pseudopachylosticta among the South American Cimbicidae. Both have striking coloration patterns, blue-black metallic body sometimes with paler coloration on some parts of the males and extensive reddish-brown areas on the thorax and sometimes abdomen in the females. The other South American genera are comparatively drab in appearance. Furthermore, Pachylosticta and Pseudopachylosticta both have the labrum raised in the middle and reduced maxillary and labial palps, with four and three palpomeres, respectively. Apart from the fore wing characters, Pachylosticta differs from Pseudopachylosticta in having the hind wing cell RS larger and cell M not reaching vein Rs, and the hind basitarsomere is longer than tarsomeres 2-4 combined in Pachylosticta spp. Finally, Pachylosticta spp. are larger (body length may exceed 1.5 cm) and more compact than Pseudopachylosticta or any other South American Cimbicidae. Pseudabia fusca reaches a body length similar to Pachylosticta spp., but is more slender in appearance. Conde (1937Conde ( , 1940 and Malaise (1939) disagreed strongly on the separation of males in Pachylosticta. Conde (1937) regarded all three species (P. albiventris, P. tibialis, P. violacea) originally described by Klug (1824) as one species, perceiving no significant differences in the male genitalia and regarding the color variation between them as a variation within P. tibialis, the type species. In contrast, Malaise (1939) correlated the color differences with a variation in the male genitalia and recognized three species; this scheme was confirmed by Smith (1988) and is also followed here (see also the key). Pachylosticta violacea is characterized by being completely darkly colored with no pale markings (Fig. 12C); male P. albiventris has an extensive creamy-white to orange patch on the underside of the abdomen (sternum and laterotergum 2 to 4/5; Fig 9A); P. tibialis has paler coloration on the upper part of the mesopleuron and the distal part of the legs (tibiae and most of the tarsi; Fig. 12A).
The two male Pachylosticta sp. from Espirito Santo, Córrego do Itá (in MNRJ) differ from all other males examined here in having a reddish-brown band formed by the different color of abdominal terga 4-6 across the abdomen (Fig. 12D); we have not placed them to species. The male from São Paulo, Valle du Rio Pardo (in MNHN) was identified by D.R. Smith as 'P. plaumanni?' (see also Smith 1988: p. 219). The thorax of this specimen is predominantly reddish brown with the following parts dark brown to black (Fig. 12B): left half of pronotum, left half of propectus, left hind leg, most of mesonotum (including mesoscutellum) except area between the median mesoscutal sulcus and right notaulus, posterior half of both tegulae, both postspiracular sclerites, posterodorsal margin of left mesepimeron (adjacent to the posterior thoracic spiracle), left ⅔ of metanotum (including the metascutellum). The right half of the 1 st abdominal tergum is reddish brown, the left dark brown. In addition, on the right apical antennomere there is an elongate lightly colored area ventrally (Fig. 12B, yellow arrow), similar to the one observed in female P. albiventris an P. apicalis (see below); the left apical antennomere is uniformly darkly colored as in all other male Pachylosticta spp. observed. The asymmetrical, harlequin-like coloration of this specimen is probably aberrant and we refrain from suggesting a species identification based on the coloration alone. Another aberrantly colored specimen is a P. albiventris male from Caetité, Bahia, Brazil (NHML); it has the distinctive pale anterior abdominal sternites but reddish brown markings posteriorly on the pronotum, in the middle of the mesonotum along the notauli and dorsally on the mesoand metapleuron as well as the proximal part of the hind tibia creamy white.
Female Pachylosticta spp. can also be separated by color differences on the body and wings. Pachylosticta albiventris and P. apicalis usually have the pro-and mesothorax reddish brown throughout (Figs 8A, 10A), whereas P. plaumanni has the median part of the pronotum and the mesoscutum darkened (Fig.  11A). However, the female Pachylosticta albiventris from Linhares has the mesonotum as well as the lower parts of the mesopleura darkened; Smith (1988) reported observing a similar color variation in the females of this species. Pachylosticta albiventris has the metathorax and abdomen uniformly blue-black metallic (Fig. 8A), whereas the other two species have only the apex of the abdomen (from segment 4 or 5) darkened (Figs 10A, 11A). In the fore wing, P. apicalis has the tip darkly infuscate contrasting with the hyaline base (Fig. 10A), whereas the other two species have the fore wings more or less uniformly infuscate (Fig. 8A). Finally, in P. albiventris and P. apicalis there is an elongate lightly colored area on the ventral side of the apical antennomere (Figs 8B-C, 10B-C); this is missing from P. plaumanni (Fig. 11B) and male Pachylosticta spp. (but see above); the function is unknown. Interestingly, this feature is illustrated in Klug (1834: plate II, fig. 5g) in the description of Plagiocera thoracica, but not mentioned in the text.
With five currently recognized species, Pachylosticta is the only non-monotypic genus of South American Cimbicidae, comprising over half the species. Nevertheless, there is a possibility that the diversity of the genus is overestimated, as males and females have only been associated for the most common species, P. albiventris. Of the remaining species, P. apicalis and P. plaumanni are known only from females, whereas P. tibialis and P. violacea are known only from males. Unfortunately, no morphological characters have been discovered that can be used to link any of these species to each other. In addition, the affinity of males with coloration more resembling that of the females has not been decided. Pachylosticta violacea males have been collected in the same localities as both P. apicalis (Parana, Rolândia) and P. plaumanni (Espirito Santo, Córrego do Itá), thus providing little evidence for associating P. violacea with any of the females of the two other species. The aberrantly colored Pachylosticta spp. males were also collected in Espirito Santo, Córrego do Itá. In general, the distributions of the described species of Pachylosticta are broadly overlapping (Fig. 16), thus providing no help for associating the sexes. DNA barcoding could potentially help to associate males and females in Pachylosticta spp. and decide if some species have different color morphs in one sex or the other. Unfortunately, the material available for this study is somewhat dated and it might not be possible to make adequate extractions from it.
Color. Coloration uniformly black to dark brown with a few lighter brown to creamy-white areas on lateral parts of pronotum, posteriorly on dorsal part of abdominal terga and on lateroterga (Fig. 13A). Legs proximally dark brown to black, creamy white from distal part of femora. Wings weakly and uniformly infuscate.
Head. Eyes slightly converging ventrally, inner margins slightly incurved. Posterior ocelli at level with dorsal margin of eyes. Toruli in middle of face, slightly closer to median ocellus than to ventral margin of clypeus (Fig. 13B). Epistomal sulcus absent. Clypeus ventral margin straight, with slight protrusion in the middle. Gena medially less wide than width of eye, wider dorsally than ventrally. Malar space very low. Occipital carina absent. Sclerotisation between occipital and oral foramina present. Antennae with five antennomeres (Figs 1A, 13C); antennomere 1 approx. 2× as long as wide, antennomere 2 approx. as wide as long, antennomere 3 1.8× as long as antennomere 4, antennomere 5 slightly expanded distally. Labrum broad, convex, hairy, flat, distal margin slightly curved. Mandibles less than ½ the height of head, with three teeth each, inner margin not serrated (Fig. 13B). Maxilla with stipes of approx. equal width throughout, palps with six palpomeres, longer than labial palps. Labial palps with four palpomeres, palps inserting at level with maxillary palps. Postmentum drop-shaped, approx. 2× as long as wide.
tHorax. Pronotum comparatively high medially, with transverse groove extending from submedially on pronotum to posterodorsal corner; lateral groove continuous with transverse, extending ventrally on pronotum until ventral to anterior thoracic spiracle where it terminates; pronotum fused with mesopleuron ventrolaterally of spiracle from halfway between spiracle and ventrolateral corner of pronotum. Dorsal cervical sclerite present. Propectus without lateral projection, propleural sulcus present, medioventral margins of propectus widely separated, posteriorly extended into narrow points. Prosternum laterally extended, continuous with katepisternum which articulate, but does not fuse with propleuron at lateral coxal articulation point. Anterior fore tibial spur straight, simple, not much longer than posterior spur, spurs pointed and sclerotized apically. Mesonotum with distinct median sulcus and deep notauli (Fig. 13A), laterophragmal apodeme not observed, postscutellum absent. Small anterodorsal part of mesopleuron separated from rest by vertical groove (Fig. 13C), prepectus absent as separate sclerite. Horizontal carina absent laterally on mesopleuron. Posterior thoracic spiracle visible in lateral view, situated in incurvation in dorsal margin of mesopleuron. Median midcoxal articulations adjacent, only separated by small wedge of cuticle. Mesofurca not observed. Insertion of mesonotometanotal muscle on small projection on anterior margin of metanotum; cenchri approx. 2× as broad as long. Anapleural cleft present, small. Metapleuron fused with abdominal tergum 1 along dorsal margin; posteroventral metapleural apodeme not observed; paracoxal sulcus curving posteriorly, terminating in the middle of the metapleural sulcus; metacoxal foramina open dorsally, without metapleural inflection laterally. Metafurca not observed. Hind coxa less than twice as long as wide, median carina or spine not observed. Hind femoral ventral spur absent. Hind tibial apical spurs shorter than apical width of tibia. Hind basitarsomere shorter than tarsomeres 2-4, tarsal claws bifid, teeth of subequal length.
Wings. Fore wing with vein M joining Sc+R close to Rs+M; vein 2r-m posteriorly inserts on cell 2M, very close to anterior end of 2m-cu (Fig. 13A); vein 1m-cu oriented obliquely, inserting on Rs+M some distance from 2r-m (distance 1m-cu-2r-m at least ½ distance M-1m-cu on Rs+M); posterior anal vein present proximally and distally but discontinuous in the middle. Hind wing cell R1 closed; vein M discontinuous, making cells Rs and M partly confluent (Fig. 13A insert), cell M not reaching vein Rs; cross vein 2a absent.
The specimens examined here fit well with the description of Schrottky (1910). The NHML specimen has a broad creamy-white band along each side of the abdomen, covering most of the lateroterga; in contrast, the NMNH specimens have only a narrow stripe along the bend between the median terga and the lateroterga. Jörgensen (1913) and Smith (1988) considered the abdomen/body to have a metallic sheen ("obscure metalico",'mostly metallic green'). The specimens examined by us look more brownish black, with at most a faint metallic sheen on the abdomen; perhaps the color changes as the specimen ages. Schrottky (1910) and Jörgensen (1913) described Pseudabia fusca/Enslinia holmgreni as having eight or seven antennomeres, respectively, with the apical 3-4 forming the apical club; Smith (1988: fig. 33) illustrated P. fusca as having five antennomeres, with a subdivision in the middle of the club.
Indeed several subdivisions can be discerned in the specimens we have examined, but these are never distinct enough to separate antennomeres within the club as clearly as between it and the four proximal antennomeres. Hence the antenna is regarded as comprising five antennomeres, as in all other South American Cimbicidae.
The most distinctive feature of Pseudabia fusca is the interruption of vein M in the hind wings, which makes cells Rs and M partly continuous; this is a unique feature within Cimbicidae. The general habitus is also slightly different from the other South American species in that P. fusca, even though it has a body length similar to Pachylosticta spp., appears to be more slender than the comparatively compact and/or shorter members of the other cimbicid species. Among the South American Cimbicidae, P. fusca is the only species to have a well-developed median carina on abdominal tergum 1.

Other material
tHorax. Pronotum comparatively high medially, with transverse groove extending from sublaterally on pronotum to posterodorsal corner; lateral groove continuous with transverse, extending ventrally on pronotum until ventral to anterior thoracic spiracle where it terminates; pronotum fused with mesopleuron ventrolaterally of spiracle from halfway between spiracle and ventrolateral corner of pronotum. Dorsal cervical sclerite present. Propectus without lateral projection, propleural sulcus present, medioventral margins of propectus widely separated, posteriorly extended into narrow points. Prosternum laterally extended, separate from katepisterna which do not extend to lateral coxal articulation point. Anterior fore tibial spur straight, simple, not much longer than posterior spur, spurs pointed and sclerotized apically. Mesonotum with distinct median sulcus and deep notauli (Fig. 14B), laterophragmal apodeme short, lobed, postscutellum absent. Small anterodorsal part of mesopleuron separated from rest by vertical groove (Fig. 14A), prepectus absent as separate sclerite. Horizontal carina absent laterally on mesopleuron. Posterior thoracic spiracle visible in lateral view, situated in incurvation in dorsal margin of mesopleuron. Median midcoxal articulations adjacent, only separated by small wedge of cuticle. Mesofurca with mesospina, anterior arms short, lateral arms elongate. Insertion of mesonoto-metanotal muscle on anterior margin of metanotum not on conspicuous structure; cenchri approx. 3× as broad as long. Anapleural cleft present, small. Metapleuron fused with abdominal tergum 1 along dorsal margin; posteroventral metapleural apodeme absent; paracoxal sulcus curving posteriorly, terminating in the middle of the metapleural sulcus; metacoxal foramina open dorsally, without metapleural inflection laterally. Metafurca with anterior arms inconspicuous, lateral arms elongate. Hind coxa less than twice as long as wide, median carina or spine absent. Hind femoral ventral spur absent. Hind tibial apical spurs shorter than apical width of tibia. Hind basitarsomere 0.8× tarsomeres 2-4 ( Fig. 14A), tarsal claws bifid, teeth subequal in length.
Wings. Fore wing with vein M joining Sc+R close to Rs+M; vein 2r-m posteriorly inserts on cell 2M, close to anterior end of 2m-cu (Fig. 14D); vein 1m-cu oriented obliquely, inserting on Rs+M some distance from 2r-m (distance 1m-cu-2r-m at least ⅓ distance M-1m-cu on Rs+M); posterior anal vein present proximally and distally but discontinuous in the middle. Hind wing cell R1 closed; vein M terminates proximally in vein Rs, cells Rs and M separated, cell Rs reduced in size and cell M extending to vein Rs proximally (Figs 14D, 15); cross vein 2a absent.
Pseudopachylosticta subflavata resembles a smaller and less compact Pachylosticta spp. Both genera are predominantly colored blue-black metallic, and the females have extensively reddish-brown coloration on the thorax; furthermore, the labrum is raised in the middle, and the maxillary and labial palps are reduced, having four and three palpomeres, respectively. Apart from the size difference, Pachylosticta and Pseudopachylosticta mainly differ in wing characters. The pterostigma is not thickened and protruding in male Pseudopachylosticta, and the fore wing vein 1m-cu inserts on vein Rs+M more proximally, the distance between 2r-m and 1m-cu insertions on Rs+M being at least ⅓ of the distance between M and 1m-cu insertions on Rs+M; in the hind wing, the cell Rs is much smaller than cell M, allowing cell M to extend to vein Rs proximally. Another difference is that the antennal club, i.e., the 5 th antennomere, is more swollen in P. subflavata. Finally, in Pseudopachylosticta the hind basitarsomere is shorter than tarsomeres 2-4 combined, whereas the opposite is the case for Pachylosticta spp. Fig. 16. Distribution of South American Cimbicidae. Records marked with an asterisk are for states within the relevant countries for which no more precise records were available; the markers have been placed approx. in the middle of the state in question. Some records have not been plotted to avoid cluttering the map.

Discussion
Vilhelmsen 2018 retrieved Pachylostictinae as monophyletic under most analytical settings, except in implied weights analyses with low K value settings (1)(2)(3). When monophyletic, Pachylostictinae was placed as sister to Corynidinae; when not, Lopesiana was placed as sister to all other Cimbicidae, whereas the other genera came out as successive outgroups to Abiinae + Cimbicinae (see Vilhelmsen 2018 for more details on topology and character support). Putative synapomorphies for Pachylostictinae are the metapleuron with the paracoxal sulcus curving posteriorly and terminating in the middle of the metepisternum. The only consistently retrieved sister group relationship within the subfamily is Pachylosticta + Pseudopachylosticta, supported by mouthpart (labrum raised in the middle, reduced maxillary and labial palps) and ovipositor characters (1 st valvula teeth strongly asymmetric and without serrulae) as well as the distinctly metallic body color.
It seems that the South American genera form a basal clade or grade within the Cimbicidae. They retain several features probably plesiomorphic for the family (e.g., normal sized mandibles, presence of a dorsal cervical sclerite, presence of a well-developed propleural sulcus and corresponding ridge; Vilhelmsen 2018). The fossil record of Cimbicidae is restricted to the northern hemisphere, the oldest fossil is of 56 Ma and can possibly be associated with the Abiinae + Cimbicinae clade (Vilhelmsen 2018); no fossils have been associated with Pachylostictinae. The phylogenetic position, morphological diversity and geographic isolation of the South American Cimbicidae indicate that they have evolved in isolation from the rest of the family for a considerable time, probably at least since the Tertiary.
Apart from Pachylosticta albiventris, P. violacea and Pseudopachylosticta subflavata, only few records are available for each species of South American Cimbicidae, and they almost never provide any detailed information about the collecting habitat. This makes it very difficult to make inferences about the biology of these wasps and what kind of habitat they occur in. Brasilabia, Lopesiana and Pseudabia have only been collected in comparatively restricted areas, the two former in southeastern Minas Gerais, Rio de Janeiro and eastern São Paulo (all in Brazil), Pseudabia in northeastern Misiones (Argentina), Santa Catarina (Brazil) and southeastern Paraguay (Fig. 16). Most records of Pachylosticta spp. are from northeastern Argentina and southeastern Brazil, with a few outliers in Bahia, Distrito Federal, and Piauí. Pseudopachylosticta has the most aberrant distribution, with little overlap with the other genera. Most records are in northern Argentina and southern Paraguay, extending west to the base of the Andes in Argentina and Bolivia; in addition, there are a few outlying records from Mato Grosso and Piauí (both Brazil). The almost complete separation of the distribution ranges of the putative sister groups Pachylosticta and Pseudopachylosticta is the most striking pattern in the records plotted for the Pachylostictinae.
The distribution of Pachylostictinae falls within an area that is apparently restricted by the Prepuna and Puna ecoprovinces in the Andes to the west, the Caatinga and Cerrado to the north and northwest, the Atlantic Ocean to the east, and the Pampa grasslands to the south (see Morrone 2006). Pseudopachylosticta has a distribution apparently on the fringes of the Chaco Province of the Chacoan subregion, extending into the Monte and perhaps the Yungas ecoprovinces to the west and the Parana subregion to the east. Interestingly, according to Paterson et al. (2014: fig. 2) Pereskia aculeata, one of the two known host plants of Pseudopachylosticta subflavata, only occurs in the easternmost distribution range of the wasp. The two apparent clusters of Pseudopachylosticta records centered in southeastern Paraguay and northwestern Argentina in the Andean foothills, respectively, might be separated by areas where few suitable habitats are available, either because of a different climate or habitat degradation. On a more comprehensive time scale, the Pachylosticta/Pseudopachylosticta split might have been caused by a vicariance event resulting from the advent of the Chacoan subregion in the Tertiary, splitting the formerly continuous Amazonian and Parana forests (Morrone 2006). Alternatively, Pseudopachylosticta might have dispersed from the Parana to the Chacoan subregion after the formation of the latter.
Disregarding outlying records of Pachylosticta albiventris and P. violacea in Mato Grosso and Piauí, the remaining records of South American Cimbicidae fall within the distribution of the Brazilian Atlantic rainforest, the Parana forest and the Araucaria angustifolia forest provinces, all within the Parana subregion (Morrone 2006). The future prospects of the cimbicids associated with this subregion are probably bleak. The Atlantic rainforest has suffered the longest and one of the most intensive episodes of human induced depredation of all South American biomes during the last 500 years; currently, less than 15% of the area originally covered by this forest remains (https://en.wikipedia.org/wiki/Atlantic_Forest). Indeed, many of the older collection localities of Pachylostictinae are situated in what are now suburbs in the sprawling metropolises of Rio de Janeiro and São Paulo.