Eurytoma discordans Bugbee, 1951

Zhang, Y. Miles, Gates, Michael W. & Shorthouse, Joseph D., 2017, Revision of Canadian Eurytomidae (Hymenoptera, Chalcidoidea) associated with galls induced by cynipid wasps of the genus Diplolepis Geoffroy (Hymenoptera, Cynipidae) and description of a new species, Journal of Hymenoptera Research 61, pp. 1-29 : 10-12

Eurytoma discordans Bugbee

Figs 9 , 22 , 23 , 26 , 27 , 29 , 35

Eurytoma discordans Bugbee, 1951b: 220-223. Holotype female (USNM). Type data: USA, Indiana [Howe]; associated with galls induced by Diplolepis globuloides (Beutenmuller) = ( Diplolepis variabilis (Bassett)) on species of Rosa , Dec 20, 1930.

Eurytoma acuta Bugbee, 1951b: 223-234. Holotype female (USNM). Type data: USA, Utah [Price]; associated with galls induced by Diplolepis tuberculatrix xerophila (Cockerell) on Rosa , April 20, 1920. Zhang et al. 2014 (synonymy under Eurytoma discordans ).

Eurytoma calcarea Bugbee, 1951b: 240-249. Holotype female (USNM). Type data: USA, Utah [Wellsville]; associated with galls induced by Diplolepis variabilis (Bassett), September 6, 1927. Zhang et al. 2014 (synonymy under Eurytoma discordans ).

Diagnosis.

Females are distinguished from other species by the S-curved metasoma that is larger than head plus mesosoma (Fig. 27 ) and the sharply upturned ovipositor dorsad the horizontal axis of the metasoma. Males have elongated funicular segments and yellow fore- and midlegs similar to E. obtusilobae , however, it differs in the black pedicle and tegulae.

Females.

Body length 2.1-5.0 mm. Color: Black except for the following yellow - basal half of scape, pro- and mesofemur, basal pro- and mesotibia, apex of metatibia, tip of ovipositor sheaths, tarsomeres 1-4, wing veins (Fig. 9 ).

Head. 1.2 × as broad as high, umbilicate punctured (Fig. 22 ). Genal carina present, evenly sculptured; malar space 0.7 × eye height, clypeus strongly emarginate and supraclypeal area smooth (Fig. 22 ). Toruli positioned slightly above lower ocular line. Intertorular space acute dorsally, with 2 rows setae. Ratio of LOL:OOL:POL is 1:1.3:2. Head posteriorly with postgenal lamina and postgenal grooves ridged, delimited ventrally by postgenal depression. Postgena evenly setose (Fig. 23 ). Funicular segments subequal in size, longer than wide; pedicel chalice-shaped; funicular segments fusiform; F1 slightly narrowed basally, funicular segments with 2 rows of longitudinal sensilla and 3 whorls of setae (Fig. 26 ).

Mesosoma. Largely umbilicate, 1.5 × as long as broad; notauli complete, shallow. Epicnemium imbricate, flattened, with superficial submedial, shallow depressions to receive procoxa. Mesepisternum anterior to femoral depression umbilicate; mesepimeron reticulate ventrally, striolate or smooth dorsally, with longitudinal rugae originating from the posterior margin. Precoxal tooth formed by raised adscrobal carina present in lateral view. Lateral panel of propodeum and callus with umbilic punctures, distinctly delimited from median area by carinae forming irregular setose cells, median furrow delimited, forming 2 rows of irregular foveae (Fig. 25 ). Procoxa imbricate, lacking setation proximally. Mesocoxal lamella absent. Metacoxa densely setose along anterior margins, glabrate with one row of setae along posterior distal margin. Forewing hyaline, marginal vein and postmarginal vein subequal in length. Basal cell evenly setose.

Metasoma. Gaster 1.8 × as long as mesosoma in lateral view; smooth, anterior edge of gastral tergites microreticulate (Fig. 27 ). Petiole 0.7 × as long as broad in dorsal view, with projecting lateral teeth as well as mediodorsal prong. Gaster laterally compressed, S-curve shaped and not convex in lateral view, ovipositor upturned dorsad horizontal axis. Gt1-3 glabrate, Gt4 with 1-4 setae lateromedially, Gt5-8 and apex of ovipositor sheath densely setose. Gt4 strongly emarginate on posterior margin dorsally.

Male.

Body length: 1.7-3.1 mm. Color: Black, yellow areas as described for female. Sculpture as described for female (Fig. 29 ). Antennae with funicular segments longer than wide, pedunculate, F2-F5 each with 2 or more rows of apressed setae and 2 rows of longitudinal sensillae (Fig. 29 ); scape with ventral plaque in apical half. Gastral petiole in lateral view cylindrical, in dorsal view length about 1.5 × as long as greatest width, 0.7 × times length of metacoxa; evenly reticulate dorsally and ventrally, obliterated laterally.

Remarks.

This is a widespread and morphologically variable species. Bugbee (1951b) originally divided this species into 3 based on subtle morphological differences and distribution: the Eastern populations as E. discordans and western populations as E. acuta (5 subspecies), and those smaller in size as E. calcarea (6 subspecies). Upon examining additional materials it was noted that the degree of infuscation on legs and scape are variable within this species and thus cannot be used as reliable distinguishing characters. The molecular evidence presented in Zhang et al. (2014) also support the monophyly of this group, albeit with the highest intra-specific divergence compared to other eurytomids. Considering there are no distinct geographical or host differences that support three distinct species, E. acuta and E. calcarea along with their associated subspecies were synonymized under E. discordans pending further molecular or ecological studies. It is also likely that Eurytoma incerta Fullaway is the senior synonym of E. discordans given the similar description by Bugbee (1951b). Closely resembles E. obtusilobae , but can be distinguished from the latter by the coloration of the tegulae, scape, and shape of the female metasoma.

Biology.

Reared from field populations of galls induced by D. bicolor on R. blanda ; D. nodulosa on R. woodsii ; D. spinosa on R. blanda and Rosa rugosa Thunb.; D. radicum on R. acicularis ; D. tumida on R. woodsii ; D. variabilis on R. woodsii . Also reared from galls of Diastrophus nebulosus (Osten Sacken) on Rubus spp..

Material examined

(197 females, 120 males). CANADA: Alberta: Beaverlodge, 1933 (1F, CNC); Head-Smashed-In Buffalo Jump, 10.V.2011, J.D. & M.R. Shorthouse, ex Diplolepis tumida on Rosa woodsii (3F, 4M, CNCI); Edmonton, 20.IV.1942, R.W.Salt (1F, CNC); Edmonton, 6.VI.1946, R.M.Mason, ex rose gall (5F, CNC); Waterton Lakes National Park, 9.V.2007, J.D. & M.R. Shorthouse, ex Diplolepis bicolor / Diplolepis nodulosa modified by Periclistus sp. on Rosa woodsii (24F, 20M, CNCI). British Colum bia: Kelowna airport, 20.V.2008, R.G. Lalonde, ex Diplolepis variabilis on Rosa woodsii (2F, 1M, CNCI); Summerland, 2.V.1959, R.E. Leech, ex Rosa (3F, CNC); Surrey, 9.IV.1954. K. Yamanaka, ex Rubus (4F, 2M, CNC). Manitoba: Morden, 1.IX.1986, J.D. Shorthouse, ex Rosa woodsii (7F, 3M, CNCI); Sandlands F.R., em 1.VI.1944, F.I.Survey, stem gall on raspberry (2F, CNC). New Brunswick: Kouchibouguac National Park, 8.VIII.1977, S.J. Miller (3F, 9M, CNC). Ontario: Attawapiskat, 18.V.2005, M.J.T. Bodnar, ex Diplolepis spinosa on Rosa blanda (22F, 20M, CNCI); Bell’s Corners, 13.V.1940. O. Peck, Host Diastrophus nebulosus (1F, CNC); Chelmsford, 5.V.1994, S.E. Brooks, ex Periclistus pirata -modified galls of Diplolepis nodulosa (4F, 2M, CNCI); Cochrane, 24.IV.2010, J.D. Shorthouse & Y.M. Zhang, ex Diplolepis spinosa on Rosa blanda (5F, 5M, CNCI); Fort Albany, 28.V.2005, M.J.T. Bodnar, ex Diplolepis radicum on Rosa acicularis (4F, 2M, CNCI); Jockvale, 8-27.V.1955, O. Peck, Rosa blanda / Rosa rugosa (42F, 19M, CNC); Manitoulin Island, 29.IV.2011, J.D. Shorthouse, B.L. Smallwood & Y. M. Zhang, ex Diplolepis nodulosa modified by Periclistus sp. (2F, 1M, CNCI); Marmora, 20.VI.1945. G.R.Hammond. Cynipid gall on wild rose (4F, CNC); Merivale, 17.VI.1954. O. Peck, Host gall Periclistus pirata ex Rosa blanda (3F, 1M, CNC); Moose Factory Island, 23.IV.2010, J.D. Shorthouse & Y.M. Zhang, ex Diplolepis spinosa on Rosa blanda (5F, 5M, CNCI); One Sided Lake, em XII.1960. S.M. Clark (2F, CNC); Ottawa, 17-25.V.1955, O. Peck, ex Rosa rugosa (19F, 4M, CNC); Thamesville, 4.VII.1962. S.M.Clark, ex gall of wild rose (3F, CNC); Rockcliffe, 27.V.1959. S.M.Clark. gall on Rosa sp. (3M, CNC). Prince Edward Island: Eldon, J.D. & M.R. Shorthouse, 23.VIII.1992, ex Periclistus pirata -modified galls of Diplolepis nodulosa on Rosa virginiana (4F, 3M, CNCI). Québec: Aylmer, VIII.1939. E.G. Lester, Host Periclistus sylvestris (2F, 5M, CNC); Chrysostome, 23.VI.1986, ex Cynipidae on Rosa sp. (1F, CNC); Lac Mercier, 7.VIII.1937. G.S. Walley. (1F, CNC); Montréal, O. Peck, 22.V-11.VI.1962, ex D. radicum (6F, 2M, CNC). Saskatchewan: Caron, em 20-23.II.1951, F.I.Survey, rose gall (1F, 3M, CNC); Great Sand Hills, 22.IX.1999, J.D. & M.R. Shorthouse, ex Diplolepis radicum on Rosa woodsii (6F, 6M, CNCI); Snowden, 18.VII.1944, O. Peck (1F, CNC); White Fox, 17.VI.1944, O. Peck (3F, CNC).

Distribution.

Widespread, from British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Québec, New Brunswick, and Prince Edward Island (Fig. 35 ).

Figures

Figures 6 - 11. Tenuipetiolus ruber 6 Female habitus. Eurytoma iniquus 7 Female habitus. E. longavena 8 Female habitus. E. discordans 9 Female habitus. E. imminuta 10 Female habitus (length 2.0 mm). E. spongiosa 11 Female habitus (length 3.2 mm), arrow pointing to precoxal tooth formed by the adscrobal carina.

Figures 18 - 23. Eurytoma obtusilobae 18 Propodeum 20 Petiole, lateral view. E. shorthousei sp. n. 19 Propodeal spiracle 21 Petiole, dorsal view. E. discordans: 22 Head, anterior view 23 Head, posterior view.

Figure 24 - 28. Eurytoma shorthousei 24 Face in lateral view. E. longavena 25 Propodeum 28 Female metasoma, lateral view. E. discordans 26 Female antenna 27 Female metasoma.

Figure 29 - 31. Eurytoma discordans 29 Male antenna. E. longavena 30 Male antenna 31 Known localities of Tenuipetiolus ruber in Canada.

Figure 32 - 37. 32 Known localities of Eurytoma shorthousei in Canada 33 Known localities of E. iniquus in Canada 34 Known localities of E. longavena in Canada 35 Known localities of E. discordans in Canada. 36. Known localities of E. imminuta in Canada 37 Known localities of E. spongiosa in Canada.