Eustochomorpha
Eustochomorpha Girault, Neotriadomerus gen. n., and Proarescon gen. n. (Hymenoptera, Mymaridae), early extant lineages in evolution of the family
Huber, John T.
Journal of Hymenoptera Research
2017
2017-06-30
57
1
87
http://zoobank.org/5488307C-D58F-4E00-8DC9-C2ACB542A103
Huber
Huber
2017
Insecta
Mymaridae
Neotriadomerus
CoL
Animalia
Neotriadomerus
Hymenoptera
4
5
Arthropoda
genus
gen. n.
Figs 32 -152
Eustochomorpha: Lin et al., 2007: 33 (diagnosis in part, figs 132-134).
Type species. Neotriadomerus longiovipositorHuber, by present designation.
Diagnosis. Female.Antenna with funicle 8-segmented and clava 3-segmented (Figs 39, 69). Venation about 0.85-0.90 xfore wing length. Postmarginal vein distinct, uniformly thick and about 1.3-1.6 xmarginal vein length (Figs 70, 122). Hypochaeta present or, apparently, sometimes absent. Ovipositor strongly extending anteriorly under mesosoma (Figs 59, 74) at least to level of hind wing base but not or only slightly extending posteriorly beyond apex of gaster (Figs 75, 77). Male.Similar to female, but flagellum with 11 relatively wide segments (Figs 40-43, 82, 95), each with several mps; the segments progressively becoming narrower towards flagellar apex, fl11 sometimes only a little over half as wide as fl1. Genitalia encapsulated, with thick walls (Figs 124, 143) and, in lateral view, paramere thick (Figs 65, 66).
Description. Female.Body 1380-5500 in length, excluding basal sac of gaster (enclosing anterior extension of ovipositor). Colour.Generally brown (Figs 81, 128, 144, 146, 147) to dark brown, scape and pedicel, legs in part and sometimes basal sac of gaster lighter brown to yellowish. Wings hyaline, the venation light brown. Head.Head about 2.0-2.9 xas wide as long, about 1.2-1.6 xas wide as high and about 1.3-2.3 xas high as long; in lateral view with anterior surface almost flat, at most barely receding ventral to eye, slightly depressed medially compared to laterally at preorbital groove; posterior surface in lateral view slightly convex except slightly indented at postorbital groove (Figs 33, 45). Face about 1.2-1.3 xas wide as high (Fig. 32), in lateral view almost flat, barely receding from ventral margin of eye to mouth opening; subantennal grooves absent; preorbital groove ventral to level of torulus straight all the way to lateral margin of mouth opening. Torulus in somewhat circular depression about 1.2 xas high as torulus width and separated by less than 0.4 xtorulus width from transverse trabecula (Fig. 33). Vertex in lateral view usually almost in same plane as face, but sometimes almost horizontal and forming a right angle with face, and vertex posteriorly forming an almost right angle with occiput and separated from it laterally by a short transverse vertexal suture extending to or just medial to posterior ocellus but absent between posterior ocelli (Fig. 33). Ocellar triangle almost flat or raised slightly above level of rest of vertex, the mid ocellus oblique to almost vertical, lateral ocelli oblique, facing laterally or posterolaterally; ocelli with POL about 2.0 xLOL and about 1.7-1.8 xOOL (varying slightly with species); ocellar area (in cleared slide mounts) with frontofacial suture (seen as white lines) between mid and lateral ocellus, frontal suture (seen as white lines) from mid ocellus to corner of transverse trabecula, and sometimes also a median longitudinal line from mid ocellus to middle of transverse trabecula (Fig. 116). Transverse trabecula apparently separated (Fig. 67) or not (Figs 36, 37) from supraorbital trabecula; preorbital trabecula short, extending to about level of dorsal margin of torulus; supraorbital trabecula in 2 equal or unequal sections, the anterior sections diverging posteriorly, the posterior, sometimes longer, sections slightly converging, and the sutures outside posterior sections continuing onto occiput as short, almost parallel lines, the occipital grooves, ventrally to level of foramen, thus separating occiput medially from temple laterally (Fig. 68). Eye large with numerous small facets, inlateral view at most about 1.4 xas high as wide and clearly but narrowly separated dorsally from back of head (temple in lateral view at most about 0.25 xeye width). Ocular apodeme short, straight, and thin (Fig. 119, inset). Malar sulcus absent. Gena at level of ventral margin of eye at most as wide as length of malar space. Head posteriorly with curved postorbital groove extending across head above dorsal margin of occipital foramen to posterior margin of eye (Fig. 68) and separating occiput/temple dorsally from gena/postgena ventrally. Mouthparts.Labrum with 4 or 6 setae; mandible with 4 uneven teeth, the ventral one the longest (Fig. 34). Antenna.Scape about 3.0-3.9 xas long as wide, with radicle distinct from rest of scape and about 0.24-0.29 xtotal scape length; pedicel about 1.1-1.6 xas long as wide, 0.72-1.09 xas wide and about 0.36-0.42 xas long as entire scape; funicle 8-segmented (Fig. 69); clava 3-segmented (Fig. 39), 1.07-1.22 xas wide as apical funicle segment and 0.18-0.23 xas long as entire funicle. Mesosoma.About 1.8-2.4 xas long as wide, 2.4-2.8 xas long as high and 1.0-1.3 xas wide as high (card- or point-mounted specimens, air- or critical-point dried). Pronotum entire, in dorsal view clearly visible, medially about 0.3-0.6 xas long as mesoscutum; collar almost horizontal, medially flat to slightly convex and without evident shoulders (Fig. 44); neck not or barely differentiated from collar; in lateral view, pronotum with lateral surface merging smoothly into dorsal surface, with a shallow, oblique ventroanterior impression margined by an oblique groove posteriorly for reception of femur (when fore leg folded against body). Spiracle (Fig. 46) very slightly stalked, at posterolateral angle of pronotum in a slight depression and facing posterodorsally. Propleura near anterior apex not quite abutting then widening more anteriorly towards the cervical sclerites (Fig. 141). Prosternum rhomboidal, almost completely divided medially by longitudinal groove (Fig. 141). Mesoscutum about 1.1-1.6 xas long as scutellum, in dorsal view with narrow, distinctly diverging notauli (Fig. 44) appearing in slide mounts wider and shallower near transscutal articulation (Fig. 72), in lateral view almost flat except anteriorly (Figs 45, 81). Scutellum slightly longer than wide (at widest point on frenum), the anterior scutellum narrower and slightly shorter to slightly longer than transversely biconvex frenum and separated from it by an evenly curved frenal line; campaniform sensilla as far apart from each other as to lateral margin of anterior scutellum and slightly farther apart than their distance to transcutal articulation, with apex of cone-shaped fenestra not extending to level of campaniform sensilla. Axilla slightly advanced, the transscutal articulation laterally almost in line with median section, and about as wide anteriorly as width of anterior scutellum at transcutal articulation; axillar pit separated from anterior scutellum by curved axillular groove; mesophragma convex posteriorly, extending to posterior apex of propodeum (Fig. 72, faintly visible under propodeum). Prepectus rather rectangular, at widest point about 0.8 xas wide as long. Mesopleuron somewhat spindle shaped, with shallow oblique depression separating mesepisternum from mesepimeron and almost straight groove extending from anterior margin to mesocoxal insertion (Fig. 92). Metanotum with distinct biconvex (slide mount, Fig. 87) or somewhat triangular (SEM, Figs 44, 48) dorsellum and lateral panel length at hind wing articulation about one-third to half length of dorsellum. Metapleuron quadrangular, with almost straight sides (Figs 56, 123). Propo deumin lateral view weakly sloping, almost in same plane as dorsellum and in dorsal view flat medially, without median or submedian grooves or other ornamentation (Figs 44, 46, 56, 72). Propodeal spiracle facing dorsolaterally, separated from anterior margin of propodeum by much less than half its own diameter. Wings.Fore wing (Fig. 113) about 2.6-3.7 xas long as wide, evenly and densely covered with microtrichia from wing apex proximally to at most about level of distal macrochaeta but almost without microtrichiabehind submarginal vein (Figs 48, 113) and parastigma (Figs 50, 51) and just behind much or all of marginal vein (Fig. 70); an oblique and usually distinct setal line extending more or less horizontally from apical margin of wing to about halfway towards base of marginal vein; cubital line ending proximally either at about same level as remaining mictrotrichiae or extending to base of parastigma; marginal setae short, the longest not more than about 0.13 xwing width (Fig. 70). Venation complete (Fig. 122); submarginal vein with 1 proximal seta; parastigma (from distal macrochaeta to base) about 0.5-0.7 xsubmarginal vein length; marginal vein length (from distal macrochaeta to junction of stigmal and postmarginal veins) about 1.2-1.5 xparastigma length; stigmal vein short but distinct, about 0.15-0.17 xmarginal vein length, curving away from wing margin then closely paralleling it (Fig. 122), with 4 apical campaniform sensilla (Fig. 52); postmarginal vein about 1.3-1.6 xas long and as thick as mar ginalvein, with a few microchaetae along anterior margin; hypochaeta usually present, occasionally apparently absent (broken off?), much closer to proximal than distal macrochaeta; proximal campaniform sensillum near posterior margin of marginal vein just apical to distal macrochaeta. Hind wing with membrane not extending to base of wing, relatively wide medially, with a rounded apex, uniformly covered with microtrichia almost to base of membrane (Figs 49, 70). Legs.Profemur and mesofemur narrow; metafemur widest, about 1.4 xas wide as mesofemur (Figs 77, 92). Tarsi 5-segmented. Calcar (moveable protibial spur) with setae along outer margin, and with inner tine about 0.4 xas long as outer tine (Figs 53, 54). Pretarsus normal (Fig. 55). Mid and hind legs with tarsomere 1 at least as long as tarsomeres 2 + 3. Metasoma.Petiole usually ring-like, about 0.4-0.5 xas long as wide (Fig. 72) but in one (the largest) species 0.7-1.0 xas long as wide. Gaster 1.18-3.25 xas long as mesosoma. Gaster with gt1 and gt6 usually slightly the longest terga (Figs 56, 73, 89, 92). Cercus distinctly raied as a thin flap above surface of gt7 (Fig. 62) with 4 setae about equal in length (Fig. 65). Hypopygium distinct (Fig. 56), extending about 0.3-0.6 xlength of gaster, sometimes as far as level of spiracle. Ovipositor sheath barely projecting posteriorly beyond apex of gaster but strongly projecting anteriorly (inside basal sac of gaster) from at least middle of mesosoma (Fig. 74) to well in front of head (Fig. 126), apparently with 1 subapical seta. Body sculpture and setation.Sculpture generally uniform and so faint that body often appearing almost smooth and shiny (Figs 81, 82, 126- 129, 144- 147). Head with engraved, slightly transverse (longitudinal on gena and postgena) or almost isodiametric reticulations becoming raised and slightly imbricate ventrally on face and on occiput (Figs 32-34). Mesosoma with faint isodiametric to elongate reticulations either transverse, mainly on pronotum, or longitudinal, mainly on scutellum. Metasoma apparently without sculpture (Figs 56- 62) except anterior apex of basal sac of gaster in at least one species. Head with few to numerous setae on face ventral to toruli, and on gena (Figs 32-34) but one (Fig. 36) or two (Fig. 32) just medial to torulus. Vertex with 2 setae, 1 between mid and lateral ocelli and 1 more laterally. Eye orbit with 3 setae dorsoanteriorly and 3 dorsally and posterodorsally. Occiput with 1 submedial seta dorsally and, more ventrally, 1 seta sublaterally and 1 seta submedially. Gena/postgena with several setae. Pronotum with about 3 setae along posterior margin and about 5 shorter setae anteriorly. Propleuron with a few small scattered setae (Figs 44, 116). Prosternum (Fig. 141) with 1-3 setae mainly in anterior half. Mesosoma with a few short setae (not treated here) around insertions of wings and some longer setae as follows. Mesoscutum with 1 adnotaular seta in posterior half of midlobe, 1 anteromedial and 1 posterolateral seta on lateral lobe and a few small pits (Figs 44-46). Anterior scutellum with 1 seta at lateral margin just anterior to axillular groove (represented by a curved medial edge at junction with frenum). Axilla with 1 anteromedial seta and 1 lateral seta. Propodeum with 2 or, occasionally, 3 propodeal setae laterally behind spiracle. Petiole apparently with 1 minute seta ventrally on anterior margin. Gaster with setae on terga increasing in number from gt1 to gt6 but apparently none on sterna except 1 or 2 short ones laterally on basal sac of gaster and longer ones on hypopygium (Fig. 56). Gt1 with about 3 lateral and 1 dorsal in 1 row; gt2 and gt3 with a few more lateral and dorsal in 1 row; gt4-gt6 with even more in 2 or more irregular rows, those around spiracle often shorter; gt7 with about 10 setae in one row. Hypopygium with about 4 ventral setae. Cerci with 4 fairly long curved setae. Male.Similar to female. Body 1280-2560 in length (males still unknown for the largest species). Flagellum with 11 relatively wide segments (Figs 40-43, 95). Gaster (card- or point mounted specimens) narrower than mesosoma, laterally compressed, with posterior apex in dorsal view wider and in lateral view usually higher than anterior apex (at petiole). Sculpture and setation of male similar to female but with fewer setae on gt6. Genitalia encapsulated, with thick walls; aedeagal apodemes evenly curved anteriorly towards each other, and shorter than aedeagus; paramere shorter than aedeagus and high in lateral view, with 3 or 4 short apical and ventral setae. Figures 32-37. Neotriadomerusspp. 32 N. gloriosusfemale head, anterior 33 N. darlingimale head + pronotum, dorsal 34 N. gloriosuslower face + mouthparts, anterior 35 N. gloriosusmaxillae + labium, anterior 36 N. longissimushead, scape and mandibles, dorsoanterolateral 37 N. longissimusradicle, anterolateral (and showing 3-way junction of transverse, supraorbital and preorbital trabeculae). Scale bar for 32, 33, 36= 100 μm; 34= 50 μm; 35, 37= 20 μm. Figures 38-43. Neotriadomerusspp. 38 N. longissimusfemale scape-base of fl2, lateral 39 N.sp. female fl8 + clava, lateral 40 N. darlingimale apex of pedicel-base of fl2, lateral 41 N. darlingimale fl11-fl13, lateral 42 N. darlingimale fl11, lateral 43 N. darlingimale apex of fl11, lateral. Scale bar for 38= 100 μm; 39, 41= 50 μm; 40, 42, 43= 20 μm. Figures 44-49. Neotriadomerusspp. 44 N. darlingimesosoma, dorsal 45 N.sp. mesosoma, dorsolateral (arrows indicate pores) 46 N.sp. base of left wings (ventral) and surrounding mesosoma, dorsolateral 47 N. darlingifore wing base, dorsal 48 N. longissimusfore wing base, ventral 49 N.sp., hind wing attachment to fore wing, ventral. Scale bar for 44, 45, 48= 100 μm; 46, 47, 49= 50 μm. Figures 50-55. Neotriadomerusspp. 50 N. darlingimale parastigma, dorsal 51 N. longissimusfemale parastigma, ventral 52 N. darlingimale stigmal vein, dorsal 53 N. longissimusfemale calcar, lateral 54 N.sp. female calcar, dorsolateral 55 N.sp. female pretarsus, dorsolateral. Scale bar for 50, 53, 54= 50 μm; 51= 100 μm; 52, 55= 20 μm. Figures 56-60. Neotriadomerusspp. 56 N.sp. metasoma, lateral 57 N.sp. metasoma, ventral 58 N.sp. apex of metasoma, ventral 59 N.sp. mesosoma and ovipositor sac, ventral 60 N.sp. apex of ovipositor sac, lateral. Scale bar for 56, 57, 59= 200 μm; 58, 60= 50 μm. Figures 61-66. Neotriadomerusspp. 61 N.sp. apex of gaster, lateral 62 N.sp. gt7 + ovipositor apex, lateral 63 N. longissimusovipositor sac, lateral 64 N.sp. male ovipositor apex, lateral 65 N. darlingiapex of gaster, posterolateral 66 N. poweraemale genitalia, lateral. Scale bar for 61= 100 μm; 62= 50 μm; 63= 200 μm; 64-66= 20 μm.
Etymology. The name is masculine. The prefix Neois Greek for new or recent, young, + Triadomerus, apparently the closest related genus.
Distribution. Neotriadomerusspecies occur only in Australia where seven are described (below) and as many as four others are illustrated (Figs 144- 152) but not named. No fossil species are known.
Hosts and habitat. Hosts are unknown. The estimated ovipositor length, when fully extended, is about 12 mm for the largest species of Neotriadomerus. This suggests that its host might be eggs of Orthopteralaid quite deeply inside plant tissue or in soil. Perhaps only Orthoptera, but possibly Coleopteraor Cicadidae, would have eggs long enough to host a developing female parasitoid (5.9 mm long) of this species. Specimens of Neotriadomerushave been collected in a variety of habitats in all Australian states except Victoria and Tasmania. Some specimens have been collected at light, suggesting they may be active at night. Noyes and Valentine (1989: 28, and figs 49, 50) discussed AustralomymarGirault, illustrated two of the largest species, and suggested that eggs of Orthopteraor Cicadidaemight be their hosts. Several specimens (NZAC, UCRC) of the species shown in Noyes and Valentine fig. 50, are ≈55 mm long excluding the posteriorly exserted section of the ovipositor and the longest one is 6.9 mm (NZAC) (S. Triapitsyn, D. Ward, personal communication). A much smaller, undescribed specimen (CNC) of Australomymar, was reared from an unidentified taxon of Tettigoniidaefrom Pinus radiataD. Don ( Pinaceae) in Chile. I suggest here that Orthopteramight also be the hosts of Neotriadomerus.
Key to species of Neotriadomerus. Females. 1 Body 5000 long; ovipositor at least 5900 long, extending anteriorly under mesosoma to well beyond level of head (Fig. 126); mandible massive (Fig. 36) N. longissimussp. n. - Body at most about 2600 long; ovipositor at most 2240 long, extending under mesosoma at most to level of head (Figs 114, 115); mandible much smaller (Figs 32, 33, 67) 2 2(1) Fore wing with cubital line of setae extending proximally to base of parastigma, i.e., clearly proximal to other microtrichia on wing surface (Figs 70, 79, 103, 132) 3 - Fore wing with cubital line of setae extending proximally only to apex of parastigma, about level with other microtrichia on wing surface (Figs 86, 113) 9 3(2) Fl1 with 2 mps; fl2 with about 4 (5?) mps (Fig. 69) N. burwellisp. n. - Fl1 with at least 4 mps; fl2 with at least 6 mps (Figs 78, 102, 131) 4 (3) Fl2 with 2 barely overlapping whorls of mps (Figs 144, 147) 5 - Fl2 with 1 whorl of mps (Fig. 102) 6 5(4) Fl8 length/width 2.6 (Fig. 144) N.sp. 1 - Fl8 length/width 2.2 (Fig. 147) N.sp. 3 6(4) Fl1 about 0.7 xas long as fl2 (Fig. 102); remaining funicle segments longer and narrower, with fl2 and fl8, respectively, 2.5 xand 2.0 xas long as wide N. gloriosussp. n. - Fl1 at least 0.9 xas long as fl2 (Figs 78, 131); remaining funicle segments shorter and wider, with fl2 and fl8, respectively, at most 2.1 xand 1.9 xas long as wide 7 7(6) Fl2-fl7 each slightly more than 2.0 xas long as wide; clava about 3.2 xas long as wide N. poweraesp. n. - Fl2-fl7 each at most 1.6 xas long as wide; clava about 2.6 xas long as wide (Fig. 78) 8 8(7) Fl2-fl3 each about 1.6 xas long as wide N. crassussp. n. - Fl2-fl3 each almost quadrate N.sp. 2 9(2) Ovipositor extending anteriorly under mesosoma to level of head (Figs 114, 115), at least about 3.6 xas long as metatibia; funicle with at least 9 mps on each segment (Fig. 112) N. longiovipositorsp. n. - Ovipositor extending anteriorly under mesosoma to level of apex of procoxa (Fig. 92), at most about 2.8 xas long as metatibia; funicle with 6 mps on each segment (Fig. 85) N. darlingisp. n.
Key to species of Neotriadomerus. Males. Males of Neotriadomerus darlingi, Neotriadomerus longiovipositorand Neotriadomerus poweraeare known and almost certainly correctly associated with the corresponding females; males are unknown for N. burwelli, N. crassus, N. gloriosusand N. longissimus. Two unnamed males are also keyed; one (sp. 4) is not definitely associated with a female and the other (sp. 1) is definitely associated with a female. 1 Fore wing with cubital line of setae extending at least to base of parastigma, clearly proximal to other microtrichia on wing surface (Fig. 139) 2 - Fore wing with cubital line of setae extending at most to apex of parastigma (level with distal macrochaeta), about level with other microtrichia on wing surface (Fig. 95) 4 2(1) Fl6 wider, its length/width about 1.8 (Fig. 150) Neotriadomerussp. 4 - Fl6 narrower, its length/width at least 2.0 (Fig. 138) 3 3(2) Fl6 about 2.0 N. poweraesp. n. - Fl6 about 3.5 N.sp. 1 4(1) Flagellomeres each with 2 barely overlapping whorls of shorter mps (Fig. 121) N. longiovipositorsp. n. - Flagellomeres each with 1 whorl of longer mps (Fig. 95) N.? darlingisp. n.