THE AUSTRALIAN SPECIES OF MONOMACHIDAE (HYMENOPTERA: PROCTOTRUPOIDEA), WITH A REVISED DIAGNOSIS OF THE FAMILY

The family Monomachidae is considered to comprise Monomachus Klug (from Australia and South America) and Tetraconus Szépligeti (South America). A family diagnosis and key to genera are presented, and the generic placement of wing‐reduced South American females is discussed. Three Australian species of Monomachus are recognised: M. antipodalis Westwood (=M. antipodalis bendora Riek =M. osmondi Riek synn. n.), M. australicus Girault and M. hesperius sp. n. The dipterous host of M. antipodalis has Gondwanan affinities.


Introduction
The family Monomachidae is a small group with an austral-disjunct distribution: 3 species occur in southern and eastern Australia and at least 10 in South America.N o fossil monomachids are known, but the family exhibits many character states plesiomorphic within the Proctotrupoidea and is probably a very ancient taxon.Adult monomachids favour cool, moist, forest habitats.I t is reasonable to assume that the family is Gondwanan in origin.The Australian species Monomachus anripodalis Westwood has been reared from a species of Boreoiiles Hardy (Diptera: Stratiomyidae) (Riek 1970), a fly remarkable in having apterous females.The subfamily Chiromyzinae, to which Boreoides belongs, also has a largely austral-disjunct distribution, and almost certainly has a Gondwanan origin.
On the other hand the sister group of Monomachus + Tetraconus is uncertain and Riek's (1955Riek's ( , 1970) ) conglomerate family Heloridae (comprising Helorus Latreille, Austronia Riek, Monomachus, Tetraconus, Vanhornia Crawford and Roproniu Provancher) is not supported by a single apomorphy.Helorus.Austronia, Monomuchus + Tetraconus, Vanhornia and Ropronia are each morphologically and biologically very distinct and phenetically as remote from each other as are the widely recognised, polytypic proctotrupoid families (Diapriidae, Proctotrupidae, Platygastridae, Scelionidae and Pelecinidae) (Naumann and Masner unpubl.).In view of the phenetic isolation of Monomachus + Tetraconus and in the absence of a clear sister group relationship, it is more informative and less misleading to regard these 2 genera as comprising a discrete family, Monomachidae.This is a reversion to Schulz's (191 1) concept of the family Monomachidae, a concept promoted more recently by Townes (1 977) and Johnson (1982).Similarities, for example in the overlapping articulation of the pronotum and mesoscutum, suggest that the Monomachidae (comprising Monomachus and Tetraconus), Roproniidae (comprising only Ropronia) and Austroniidae (comprising only Austronia) are closely related and may form a monophyletic group.
The Australian Monomachidae comprise a small, morphologically uniform group.On the other hand the South American Monomachidae are more heterogeneous.Manotypic Tetraconus is in most respects a typical Monomachus and several authors (Schulz 191 1; Townes 1977) have questioned whether the presence of genal  additional, undescribed, flightless species (from Peru and Chile) in which the female is apterous, the petiole very short and the radial cell of the male fore wing open.These 2 species may deserve generic separation from Monomachus.

Biology
Riek's (1970) rearing of M .antipodalis from mature larvae and puparia of a species of Boreoides (Diptera: Stratiomyiidae: Chiromyzinae) is the only known host association for the Monomachidae.The relatively small, male Boreoides hosts each produce 1 M .antipodalis.Several wasps can complete their development successfully in each of the larger, female hosts.Boreoides has a more restricted distribution than does Monomachus (Fig. 39).M .australicus Girault  biological studies of this economically important species (L.N .Robertson pers.comm.), suggesting that Chiromyza spp.are the more likely hosts of M .australirus and M .hesperius.
Adults of Australian Monomachus spp.tend to fly during the cooler months.M. antipoddis is almost exclusively an autumn-winter species, and in southern Australia is 1 of the few wasps active when the daily temperature range is 0-9°C.M. australicus, from north-eastern Australia, flies predominantly during late summer and winter, but records from the Bellenden Ker Range suggest that even in tropical regions at high altitudes (over 1000 m) this species has a longer summer flight period.M .hesperius is active from late summer to early winter.
Monomachus spp.occur in rainforest, in wet sclerophyll forest and in moist pockets in otherwise dry sclerophyll forest.M .anripodalis has been recorded from domestic gardens where these are relatively shaded and moist.Adult wasps are collected by Malaise traps and are attracted to light; they are rarely taken by diurnal sweeping.A series of 6 females of M. antipodalis was recovered from the stomach of a trout caught on the Fish R., N.S.W.

Biogeography
Australian Monomachus spp.are allopatric and restricted to the higher rainfall regions of eastern and southern Australia (Fig. 39).The absence of Tasmanian records may reflect a lack of collecting during cooler months.Their distribution falls almost entirely within the known distribution of the Chiromyzinae, which includes the only known host of a species of Monomachus.The Chiromyzinae are a primitive element within the Australian Stratiomyidae.They are represented elsewhere by several genera in New Zealand and South America and by the more widespread Inopus (Colless pers.comm.).Their largely Gondwanan distribution resembles that of Monomachus, except that the latter is absent from New Zealand.

Key to Australian species
.
Macropterous.Fore wig-Radial cell closed.Junction of m-cu and Cu, proximal to bifurcation of Cu,.
Hind wing-M continuous between Cu, and lrm/Rs (Fig. 35) or narrowly interrupted near Cu, (Fig. 36); always with at least basal stump of M beyond Cu,.

Mule
Differing from female as follows: Lengths, indices as in Table 1.
Head-Ocellar area sometimes smooth with only a few wrinkles close to ocelli.Postocellar area usually broadly smooth.Gena not as strongly swollen.Clypeal margin produced, usually rounded, rarely distinctly tridentate.
Fort wing-Distal remnant of Rs + M proximal to m-cu sometimes present.

Female
Body and wing lengths, indices as in Table 1.
Metasoma-Petiole: anterodorsally smooth or with a few weak wrinkles; in lateral view more or less sinua te.
Colour-Fore wing hyaline.Body predominantly black to dark brown; clypeus, mandible (excluding teeth), flagellum, legs, ventral metasoma (in part) brown; small patch on vertex between lateral ocellus and compound eye, lateral lobe of mesoscutum, mesoscutellum reddish orange; or body more extensively reddish brown to reddish orange with black to dark brown restricted to lateral pronotum, mesoscutum anteriorly and laterally, mesopleuron, mesoscutellum laterally and posteriorly, metanotum (excluding dorsellum) and propodeum.

Male
Differing from female as follows: Lengths, indices as in Table I .Head-Clypeal margin weakly produced, broadly convex.Mesosoma-Pronotum sometimes uniformly very sparsely punctate.Propodeum: punctation sometimes uniformly very weak.

Discussion
M .hesperius is most similar to M. australicus, especially with respect to the shape of the head and mandible, and the development of the occipital carina.The 2 species are distinguished as detailed in the key.Females and males of M .hesperius have been correlated by similarities in wing venation, sculpturing and colour, and by collecting records.The holotype and 3 of the paratypes were collected at light, by the same collectors, during a 14-day period, although at 4 different localities between 80 and 190 km apart.
The specific name is from the Latin hesperius (western).

Table 1 .
Ranges of body and wing lengths, ratios of measurements: Australian Monomachus spp.