Megastigmidae

 Male Chromeurytoma, from John Heraty.

Belongs within: Chalcidoidea.
Contains: Bootanelleus, Megastigmus.

The Chromeurytominae are an Australian group of chalcidoid wasps associated with plant gall-makers and leaf-miners.

The Megastigminae is a group of wasps characterised by a prominent stigmal vein in the forewing. The majority of species are phytophagous, though many are inquilines or parasites of other gall-makers.

The Chromeurytominae: Australo-Asian mystery wasps
Published 10 September 2015

One of the most diverse groups of micro-wasps is the Chalcidoidea, a bewildering array of intricate little jewels. A number of chalcidoid taxa have been extensively studied due to their roles as parasitoids of insect pests, but there are also many groups of chalcidoids that remain little known. One such group is the Chromeurytominae.

The Chromeurytominae are a small group of chalcidoids primarily known from Australia, where they are represented by two genera, fourteen species of Chromeurytoma and the monotypic Asaphoideus niger (Bouček 1988). A single species, Pitayana coccorum, has also been described from Bangladesh (Bouček & Bhuiya 1990). Characteristic features include a relatively large subrectangular pronotum (the first segment of the thorax) and an antenna with six segments between the pedicel and the clava (the club). They are more or less shiny, often with a blue or green metallic gloss, and the gaster is fairly robust and does not collapse in preserved specimens. The affinities of the Chromeurytominae have been rather uncertain and the subfamily was only established by Bouček in 1988. Chromeurytoma itself was originally described in the family Eurytomidae, with which it shares the large pronotum. Other features suggest a relationship with the family Torymidae, such as an occipital carina (a ridge around the back of the head) and prominent cerci. Currently the Chromeurytominae are treated as part of the family Pteromalidae, which is not really saying too much. As our understanding of chalcidoid phylogeny has improved in recent years, it has largely confirmed what many workers had long suspected: that once you account for the other families, the Pteromalidae is pretty much just what’s left over. Nevertheless, the broad-scale analysis of chalcidoids by Heraty et al. (2013) places the Chromeurytominae within a cluster of ‘pteromalid’ subfamilies, closer to the type subfamily Pteromalinae than to either the Eurytomidae or Torymidae.

The chromeurytomines are a bit of a mixed bag in terms of host species, but there is the common thread that their hosts are immobile or semi-sedentary plant-feeding insects. Pitayana coccorum attacks mealybugs and other soft scales, with multiple larvae potentially developing on a single host. Asaphoideus niger attacks the citrus leaf-miner Phyllocnistis citrella. The Chromeurytoma species are associated with galls on trees such as Eucalyptus; presumably they are parasites of the insects forming the galls.

Systematics of Megastigmidae
<==Megastigmidae [Megastigmides]HB13
    |--ChromeurytominaeBM22
    |    |--Asaphoideus Girault 1913B88
    |    |    `--*A. niger Girault 1913B88
    |    |--PatiyanaBM22
    |    `--Chromeurytoma Cameron 1912 (see below for synonymy)B88
    |         |--*C. clavicornis Cameron 1912B88
    |         |--C. beerwahi (Girault 1926) [=Amonodontomerus beerwahi]B88
    |         |--C. emersoni (Girault 1915) [=Holasaphes emersoni]B88
    |         |--C. gregi (Girault 1915) [=*Holasaphes gregi]B88
    |         |--C. iucunda (Girault 1921) [=Amonodontomerus iucundus]B88
    |         |--C. megastigmoides (Girault 1926) [=Amonodontomerus megastigmoides]B88
    |         |--C. miltoni (Girault 1931) [=*Euryperilampus miltoni]B88
    |         |--C. montana (Girault 1929) [=Amonodontomerus montanus]B88
    |         |--C. mycon (Walker 1839) [=Miscogaster mycon]B88
    |         |--C. nelo (Walker 1839) [=Miscogaster nelo]B88
    |         |--C. noblei (Girault 1940) [=Amonodontomerus noblei]B88
    |         |--C. poeta (Girault 1939) [=Amonodontomerus poeta]B88
    |         |--C. silvae (Girault 1921) [=Amonodontomerus silvae]B88
    |         `--C. viridis (Girault 1913) [=*Amonodontomerus viridis]B88
    |--Keirana Bouček 1988 [Keiraninae]BM22
    |    `--*K. longicollis Bouček 1988B88
    `--MegastigminaeHB13
         |  i. s.: Mangostigmus Bouček 1986B88
         |           `--*M. amraeus [=Neomegastigmus amraeus]B88
         |         Ianistigmus Bouček 1988B88
         |           `--*I. tatianae Bouček 1988B88
         |         Westralianus Bouček 1988B88
         |           `--*W. microstigma Bouček 1988B88
         |         Malostigmus Bouček 1988B88
         |           `--*M. pergratus (Girault 1915) [=Bootanomyia pergrata]B88
         |         Xenostigmus Riek 1966B88
         |           |--*X. mirostigmus Riek 1966B88
         |           |--X. longistigmus Riek 1966B88
         |           `--X. similis Riek 1966B88
         |         Bootanomyia Girault 1915 [incl. Epibootania Girault 1937]B88
         |           |--*B. smaragdus (Girault 1915) [=Megastigmus (*Bootanomyia) smaragdus]B88
         |           |--B. gemmaB88
         |           |--B. guttatipennis (Girault 1937) [=*Epibootania guttatipennis]B88
         |           `--B. viridiscutellum (Girault 1915) [=Megastigmus (Bootanomyia) viridiscutellum]B88
         |         Bootania Dalla Torre 1897 (see below for synonymy)B88
         |           |--*B. leucospoides [=*Metamorpha leucospoides]B88
         |           |--B. gigantea (Girault 1928) [=Pulvilligera gigantea]B88
         |           |--B. japonica [=Megastigmus japonicus, *Macrodasyceras japonicus]B88
         |           |--B. maxima (Strand 1911) [=*Pulvilligera maxima]B88
         |           |--B. neocaledonica (Milliron 1950) [=Pulvillgera neocaledonica]B88
         |           |--B. pilicornis [=*Eutanycormus pilicornis]B88
         |           |--B. ruficeps [=*Spilomegastigmus ruficeps]B88
         |           |--B. solomonensis (Milliron 1950) [=Pulvilligera solomonensis]B88
         |           `--B. titanus (Girault 1939) [=Epimegastigmus titanus, Megastigmus titanus]B88
         |--+--BortesiaHB13
         |  `--BootanelleusMH11
         `--+--MegastigmusMH11
            |--Paramegastigmus Girault 1915MH11, B88
            |    `--*P. flavus (see below for synonymy)B88
            `--Neomegastigmus Girault 1915HB13, B88
                 |--*N. petiolatus Girault 1915 [incl. N. rufithorax var. nelsonensis Girault 1915]B88
                 |--N. collaris Girault 1915B88
                 |--N. filius Girault 1915B88
                 |--N. lividus Girault 1915 [incl. N. lividus var. badius Girault 1915]B88
                 |--N. rufithorax Girault 1915B88
                 |--N. saltensis Girault 1915B88
                 `--N. varius Girault 1915B88
Nomen nudum: Bootanomyia unistriata Girault 1928B88

Bootania Dalla Torre 1897 [=Metamorpha Walker 1862 non Huebner 1819; incl. Eutanycormus Cameron 1909, Macrodasyceras Kamijo 1962, Pulvilligera Strand 1911, Spilomegastigmus Cameron 1905]B88

Chromeurytoma Cameron 1912 [incl. Amodontomerus Girault 1913, Euryperilampus Girault 1931, Holasaphes Girault 1915]B88

*Paramegastigmus flavus [=Spilomegastigmus flavus, Megastigmus (*Paramegastigmus) flavus; incl. M. (P.) immaculaticorpus Girault 1915]B88

*Type species of generic name indicated

References

[B88] Bouček, Z. 1988. Australasian Chalcidoidea (Hymenoptera): A biosystematic revision of genera of fourteen families, with a reclassification of species. CAB International: Wallingford (UK).

Bouček, Z., & B. A. Bhuiya. 1990. A new genus and species of Pteromalidae (Hym.) attacking mealybugs and soft scales (Hom., Coccoidea) on guava in Bangladesh. Entomologist’s Monthly Magazine 126: 231–235.

[BM22] Burks, R., M.-D. Mitroiu, L. Fusu, J. M. Heraty, P. Janšta, S. Heydon, N. D.-S. Papilloud, R. S. Peters, E. V. Tselikh, J. B. Woolley, S. van Noort, H. Baur, A. Cruaud, C. Darling, M. Haas, P. Hanson, L. Krogmann & J.-Y. Rasplus. 2022. From hell’s heart I stab at thee! A determined approach towards a monophyletic Pteromalidae and reclassification of Chalcidoidea (Hymenoptera). Journal of Hymenoptera Research 94: 13–88.

[HB13] Heraty, J. M., R. A. Burks, A. Cruaud, G. A. P. Gibson, J. Liljeblad, J. Munro, J.-Y. Rasplus, G. Delvare, P. Janšta, A. Gumovsky, J. Huber, J. B. Woolley, L. Krogmann, S. Heydon, A. Polaszek, S. Schmidt, D. C. Darling, M. W. Gates, J. Mottern, E. Murray, A. D. Molin, S. Triapitsyn, H. Baur, J. D. Pinto, S. van Noort, J. George & M. Yoder. 2013. A phylogenetic analysis of the megadiverse Chalcidoidea (Hymenoptera). Cladistics 29: 466–542.

[MH11] Munro, J. B., J. M. Heraty, R. A. Burks, D. Hawks, J. Mottern, A. Cruaud, J.-Y. Rasplus & P. Jansta. 2011. A molecular phylogeny of the Chalcidoidea (Hymenoptera). PloS One 6 (11): e27023.

Leave a comment

Your email address will not be published. Required fields are marked *