Belongs within: Eulophinae.
Sympiesis is a genus of wasps whose larvae are ectoparasitic on the larvae of leaf-mining Lepidoptera. As currently defined, Sympiesis encompasses a wide range of morphologies. For instance, males may have the antennae either branched or unbranched (Bouček 1988).
Simply Sympiesis
Published 28 May 2015
We often imagine that parasites select their hosts largely on the basis of type: one parasite prefers caterpillars, for instance, while another prefers flies. However, sometimes what is important is not so much what type of host a parasite attacks, as where they find it. The wasp in the photo above represents Sympiesis, a sizeable genus (the Universal Chalcidoidea Database lists over 130 species) of microscopic parasitoid wasps found worldwide. The majority of Sympiesis larvae attack the larvae of Lepidoptera, but others feed on the larvae of Diptera. A few have been recorded as hyperparasitoids, attacking the larvae of other parasitic wasps. The main thing that all hosts of Sympiesis have in common, though, is that they are all found in secluded, vegetative habitats: either mining in leaves, or in retreats formed by rolling or tying leaves (sometimes boring in stems). Depending on species, Sympiesis larvae may be either ectoparasites or endoparasites: those species feeding on leaf-rolling hosts tend to be ectoparasites, while those targeting leaf-miners are endoparasites (Miller 1970).
Sympiesis is a genus of the chalcid family Eulophidae. Eulophids used to be the subject of some disagreement between myself and a colleague of mine about their ease of recognition. Eulophids are a diverse group in appearance, coming in a bewildering array of shapes and colours. However, I have always maintained that they are nevertheless readily recognisable. Whatever their appearance, eulophids seem to always a distinctive stamp of ‘eulophid-ness’. They tend to be slender, relatively soft-bodied wasps, often with a flat top to the gaster. Most identification guides will tell you to look out for their four-segmented tarsi (as opposed to the five-segmented tarsi of most other chalcid wasps); eulophid tarsi are rendered even more recognisable by the point that, though they have less segments than the tarsi of other chalcids, they are not any shorter so the individual tarsal segments are all relatively long. The features distinguishing Sympiesis from other eulophid genera are, of course, finer and require fairly close examination: notably, they have relatively few dorsal setae (only four on the scutellum) (Bouček 1988). As far as I know, they are mostly metallic green in coloration.
As with many eulophids, males of Sympiesis usually differ from females in having long branches on the antennae. However, the first species of the genus to be described, the European Sympiesis sericeicornis, is distinctive in that these antennal branches are much reduced so that the males’ antennae look little different from the females’ (if you look very closely, they still have just a bit of a finger on each of the middle antennal segments). This led historically to a fair bit of confusion in the recognition of Sympiesis, with many species originally being placed in segregate genera (often with tongue-twistery compound names such as Asympiesiella or Sympiesonecremnus; thank you again, Alexandre Girault). Even now, the status of Sympiesis with regard to some related smaller genera could do with further investigation; we may yet see it grow again.
Systematics of Sympiesis
Characters (from Bouček 1988): Antenna with scapes at most only slightly exceeding ocelli, flagellum not distinctly clavate, in male often with three branches, female funicle four-segmented; scutellum not transverse, without sublateral grooves, bare except for four setae; postmarginal vein ending far from wing apex; gaster dorsally collapsing.
<==Sympiesis Förster 1856 (see below for synonymy)B88 |--*S. sericeicornis [=Eulophus sericeicornis]B88 |--S. agromyzae Gahan 1913GM79 | |--S. a. agromyzaeG17b | `--S. a. pennsylvanicus Girault 1917G17b |--S. australiensis (Girault 1913) [=*Diaulomella australiensis]B88 |--S. bimaculatus Crawford 1913GM79 [incl. S. bimaculatipennis Girault 1917G25, GM79] |--S. boasi (Girault 1913) [=*Sympiesonecremnus boasi]B88 |--S. campbellensis (Kerrich & Yoshimoto 1964) [=Ardalus campbellensis]B88 |--S. coloni Girault 1917G17c |--S. consona (Girault 1915) [=*Pardiaulomella consonus]B88 |--S. cyaneipurpurea (Girault 1915) [=*Diaulomorphella cyaneipurpurea]B88 |--S. dandoloni Girault 1917G17a |--S. dolichogaster Ashmead 1888 (see below for synonymy)B88 |--S. felti Crawford 1911GM79 |--S. flavipes Ashmead 1886GM79 |--S. fucosa (Girault 1915) [=Opheliminus fucosus]B88 |--S. grotii (Girault 1913) [=*Opheliminus grotii, O. grotiusi Girault 1913]B88 |--S. guttatipennis Girault 1917G17b |--S. hawaiiensis (Ashmead 1901) [=Ophelinus (l. c. for Ophelimus) hawaiiensis]B88 |--S. lexingtonensis Girault 1917G17e |--S. longfellowi (Girault 1913) [=Opheliminus longfellowi]B88 |--S. longiventris (Girault 1913) [=*Pseudopheliminus longiventris, Asympiesiella longiventris]B88 |--S. miltoni Girault 1917G17c |--S. maculipes Crawford 1913GM79 |--S. marilandia Girault 1917G17d |--S. marylandensis Girault 1917GM79 |--S. mauiensis (Ashmead 1901) [=Ophelinus (l. c. for Ophelimus) mauiensis]B88 |--S. nigrifemora Ashmead 1888GM79 |--S. nigripes Ashmead 1888GM79 [incl. S. massasoit Crawford 1913G25, GM79] |--S. pulcherrima (Dodd in Girault 1915) [=Opheliminus pulcherrimus]B88 |--S. rex Girault 1917G17a |--S. saintpierrei (Girault 1913) (see below for synonymy)B88 |--S. spadiceipes (Girault 1915) [=*Pardiaulomyia spadiceipes]B88 |--S. speciosa (Girault & Dodd in Girault 1915) [=*Pronecremnus speciosus]B88 |--S. stigmatipennis Girault 1917G17b |--S. stigmatus Girault 1917G17b |--S. superba (Girault 1915) [=Asympiesiella superbus]B88 |--S. tischeriae Ashmead 1888GM79 |--S. uroplatae Howard 1885GM79 [incl. S. unicarinata Ashmead 1894G17b, GM79] `--S. wordsworthi Girault 1917G17c
Sympiesis Förster 1856 [incl. Asympiesiella Girault 1913, Cladosympiesis Graham 1959, Diaulomella Girault 1913, Diaulomorphella Girault 1915, Moroceras Erdös 1954, Necremnomyia Girault 1913, Opheliminus Girault 1913, Pardiaulomella Girault 1915, Pardiaulomyia Girault 1915, Pronecremnus Girault & Dodd in Girault 1915, Pseudopheliminus Girault 1913, Sympiesonecremnus Girault 1913, Teleogmus Förster 1856]B88
Sympiesis dolichogaster Ashmead 1888 [incl. Asympiesiella nelsonensis var. gracilis Girault 1915, A. india Girault 1916, *A. nelsonensis Girault 1913, Sympiesis nelsonensis Girault 1914]B88
Sympiesis saintpierrei (Girault 1913) [=*Necremnomyia saintpierrei; incl. Sympiesonecremnus aenella Dodd in Girault 1915, N. variscutum 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).
[G17a] Girault, A. A. 1917a. New chalcid flies. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 72–77).
[G17b] Girault, A. A. 1917b. Descriptiones stellarum novarum. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 80–101).
[G17c] Girault, A. A. 1917c. Descriptiones hymenopterorum chalcidoidicarum variorum cum observationibus. III. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 102–111).
[G17d] Girault, A. A. 1917d. Chalcidoidea nova Marilandensis. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 112–113).
[G17e] Girault, A. A. 1917e. Descriptiones hymenopterorum chalcidoidicarum variorum cum observationibus. V. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 116–131).
[G25] Girault, A. A. 1925. Indications (in new insects) of ruling power and laws in nature. Privately published (reprinted: Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 184–186).
[GM79] Gordh, G., A. S. Menke, E. C. Dahms & J. C. Hall. 1979. The privately printed papers of A. A. Girault. Memoirs of the American Entomological Institute 28: 1–400.
Miller, C. D. 1970. The Nearctic species of Pnigalio and Sympiesis (Hymenoptera: Eulophidae). Memoirs of the Entomological Society of Canada 102 (Suppl. S68): 5–121.