Eurytoma afra, BOHEMAN, 1836

Delvare, Gérard, Gebiola, Marco, Zeiri, Asma & Garonna, A. P., 2014, Revision and phylogeny of the European species of the Eurytoma morio species group (Hymenoptera: Eurytomidae), parasitoids of bark and wood boring beetles, Zoological Journal of the Linnean Society 171 (2), pp. 370-421 : 377-383

EURYTOMA AFRA BOHEMAN, 1836 ( FIG. 10A–D )

Eurytoma afra Boheman, 1836: 242–243 . Original description. Sweden. Graham, 1970: 147 – revised synonymy, comparison with E. morio .

Decatomidea polygraphi Ashmead, 1894: 322–323 . Original description. USA, Virginia.

= Eurytoma albimana Boheman, 1836 ; Dalla Torre, 1898: 332.

Eurytoma saliciperdae Mayr, 1878 ; Ferrière, 1950: 381 (misidentification).

Ipideurytoma spessivtsevi Boucˇek & Novicky, 1954: 269–261. Original description. Sweden.

Host: Trypodendron signatum (Fabricius, 1787) (under Xyloterus lineatus ). Zerova, 1998: 32: = Eurytoma polygraphi (Ashmead) .

Ipideurtytoma [sic] polygraphi (Ashmead) : Bugbee, 1956: 506.

= Decatomidea polygraphi Ashmead syn. nov.

KEY TO EUROPEAN SPECIES OF EURYTOMA BELONGING TO THE MORIO GROUP

Females

1. Metacoxa densely setose dorsally from base ( Figs 4N , 22D, 27F). Marginal vein somewhat to evidently thick- ened, 2.90–4.80 times as long as wide (Figs 11G, 22H). Lower surface of costal cell most often bearing numerous short setae, sometimes entirely setose or leaving a narrow posterior bare stripe (Figs 11F, 22G)..............2

1′. Metacoxa bare dorsally at base or marginal vein not thickened, at least 6.00 times as long as wide (Figs 12H, 13G, 25J, 30J). Setation of lower surface of costal cell as usual, not especially dense (Figs 16H, 25J, 30J)...............................................................................................................................................6

2(1). Notauli appearing as complete impressed lines, not obliterated by the sculpture of the mesoscutum (Fig. 35A, C). Valvulae generally ascending only slightly (Figs 11H, 27H)...........................................................3

2′. Notauli hardly impressed and/or obliterated by the sculpture (Figs 14D, 22C). Valvulae evidently ascending (Figs 15A, 22I)...........................................................................................................................5

3(2). Body with following parts light: lateral panel of pronotum anteriorly, pro- and mesocoxae, acropleuron, edge of oral fossa. Marginal vein thick, 2.90 times as long as wide (Fig. 11G). Wing membrane with relatively broad diffuse infumation posterior to marginal vein. Median channel of propodeum with complete, mostly regular, median ridge (Fig. 11E)............................................................... Eurytoma aloisifilippoi (Russo, 1938)

3′. Body with lateral panel of pronotum, pro- and mesocoxae, acropleuron, edge of oral fossa dark. Marginal vein less thick than in alternate, at least 3.50 times as long as wide (Fig. 29D, H). Median channel of propodeum without, or with partial, irregular and sinuous median ridge.............................................................4

4(3). Marginal vein wider than in the alternative, 3.50–4.50 times as long as wide and widening distally (Fig. 29H). Lower surface of costal cell completely densely setose (Fig. 29F), the setae mostly white and relatively short (Fig. 29E, G)............................................................................... Eurytoma striolata Ratzeburg, 1848

4′. Marginal vein slender than in the alternative, about 4.85–5.00 times as long as wide, not widening distally (Fig. 29D). Lower surface of costal cell with a narrow posterior bare stripe (visible only when the wing is tilted; Fig. 29B), setation longer and mostly dark (Fig. 29C). ............. Eurytoma melanoneura Walker, 1871

5(2′). Walls of punctures strongly raised on mesonotum, forming transverse crests on pronotum (Fig. 14D–F). Head long and globose, 1.65–1.70 times as wide as long (Fig. 14B) ........................ Eurytoma cristata sp. nov.

5′. Walls of punctures not strongly raised, not forming crests on pronotum (Fig. 22C). Head relatively shorter, 1.75–2.0 times as wide as long (Fig. 22A). ............................................ Eurytoma morio Boheman, 1836

6(1′). Frons forming blunt angle with vertex, which is in the same plan as the pronotal collar (Fig. 10B). Head transverse in frontal view, subtrapezoidal (Fig. 10A). Pronotum with large and well-delimited yellow spots, visible laterally (Fig. 10B). Pronotal collar with small but relatively deep punctures, separated by coriaceous interspaces (Fig. 10C). Axillar grooves narrow and superficial (Fig. 10C). Postgenal carina strongly raised, appearing triangular in lateral view (Fig. 10B) ........................................ Eurytoma afra Boheman, 1836

6′. Head rounded in frontal view (Fig. 21A) and/or not so transverse (Fig. 13A). Frons as usual, merging pro- gressively towards vertex (Fig. 18C). Lateral panel of pronotum generally completely black (Fig. 20D), some- times with diffuse yellowish spot. Pronotal collar generally densely punctured, the points separated by narrow interspaces (Figs 13D, 18F), or punctures shallow (Fig. 24D). Axillar grooves deep except sometimes anteri- orly. Postgenal carina not so raised (Fig. 18C).................................................................................7

7(6′). Pronotum finely and sparsely punctured, the points rounded, interspaces distinctly coriaceous (Fig. 5G). Lower face entirely strigose, with radiating crests reaching eyes and antennal toruli (Fig. 21A). Head long and globose, 1.60 times as wide as long when seen in dorsal view, with very convex frons (Fig. 21B). Parasitoids of bark beetles .......................................................................................... Eurytoma maura Boheman, 1836

7′. Pronotum densely areolate, punctured with narrow interspaces (Figs 13D, 18F). Lower face most often partly punctured and showing a supraclypeal smooth stripe (Figs 25D, 32B). Head often more transverse than in alternate, 1.70–2.00 times as wide as long (Figs 12A, 13B, 18B, 30B). Hosts sometimes different or species seed eaters................................................................................................................................8

8(7′). Small size species (2.40–2.90 mm) with elongate gaster (Fig. 24F, 25K). At least procoxa (as in Fig. 26A) and ovipositor reddish, the former sometimes brownish but never black. Species associated with gall midges of the genus Rhabdophaga on Salix spp.............................................................................................9

8′. Species of larger size (more than 3.0 mm) and/or with relatively less elongate gaster (Figs 12G, 18K, 30K). Procoxa black, ovipositor dark, at most lighter at apex. Parasitoids of bark beetles or other xylophagous Coleoptera within seeds of pines or seed eaters on coniferous trees .................................................................. 10

9(8). Puncturation on pro- and mesonotum superficial with coriaceous interspaces (Fig. 24D). Head long and globose, 1.55 times as wide as long, with very convex frons (Fig. 24B). Lower face almost smooth, showing only ra- diating striolae. Vertex and upper frons coriaceous (Fig. 24C). Lateral prepectus not delimited from sublateral, the reticulate sculpture continuing there (Fig. 24E). Femora and tibiae more extensively fuscous .............. ......................................................................................................... Eurytoma nobbei Mayr, 1878

9′. Puncturation on mesonotum prominent, not superficial (Fig. 25F). Head shorter than in alternate, 1.75 times as wide as long (Fig. 25A). Lower face mostly punctured with short radiating crests (Fig. 25D). Lateral prepectus delimited ventrally by a distinct ridge (as in Fig. 26A). Legs mostly reddish, except metacoxa and small fuscous spots on meso- and metafemora............................................................. Eurytoma saliphila sp. nov.

10(8′). Gaster relatively short and not laterally compressed, at most as long as mesosoma when excluding the hori- zontal ovipositor (Figs 30K, 16K).................................................................................................11

10′. Gaster distinctly longer than mesosoma and laterally compressed, with ovipositor ascending (Figs 12G, 13H, 18K, 19F, 20G, 31A)..................................................................................................................12

11(10). Metacoxa sparsely setose dorsally (Fig. 30I). Ovipositor completely reddish (Fig. 30K). Notauli broad and deeply impressed (Fig. 30F). Clypeus distinctly emarginate on ventral margin (Fig. 30A). Head less transverse than in alternate when seen in frontal view, somewhat roundish (Fig. 30A) ............. Eurytoma sylviae sp. nov.

11′. Metacoxa bare dorsally. Ovipositor light only at apex (Fig. 16K). Notauli shallow (Fig. 16F). Clypeus hardly emarginate (Fig. 16A). Head more transverse in frontal view, subtrapezoidal (Fig. 16A). Nearctic species intro- duced in Europe, seed eater on Pseudotsuga menziesii .................................... Eurytoma gatesi sp. nov.

12(10′). Anterior outline of mesepisternum with blunt angle in front of mesocoxae, delimiting anteriorly an apparent ventral shelf when seen in lateral view (Figs 18G, 31B). Lower face entirely strigose, the radiating crests reaching eyes and antennal toruli (Fig. 18A)................................................. Eurytoma ithma sp. nov.

12′. Mesepisternum with flat or hardly convex anterior outline (Figs 12F, 13E, 19D, 20D). Lower face with median smooth stripe, crests short (Fig. 13A)........................................................................................... 13

13(12′). Gaster elongate, at least 1.90 times as long as third gastral tergite height (Figs 12G, 13H, 19F). Ovipositor moderately ascending. All funicular segments clearly longer than wide (Figs 12B, 13C, 19C). Clypeus and subantennal stripe smooth, lower face otherwise punctured (Fig. 13A) ............................................... 14

13′. Gaster less elongate, 1.60 times as long as third gastral tergite height, with ovipositor strongly ascending (Fig. 20G). Funicular segment shorter, F4–F5 hardly longer than wide (Fig. 20B). Lower face punctured strigose (Fig. 32B, C). Larvae phytophagous in seeds of Larix spp.............................. Eurytoma laricis Yano, 1918

14(13). Vertex with coriaceous transverse stripe between lateral ocelli (Fig. 19B). Head globose in dorsal view, 1.77 times as wide as long, the outline of frons strongly convex (Fig. 19A). Outline of genae convex when seen in frontal view. Scape entirely black on holotype. Reared together with xylophagous beetles......................... ................................................................................................... Eurytoma kangasi Hedqvist, 1966

14′. Vertex entirely punctured (Figs 12A, 13B). Head more transverse in dorsal view, 1.85–1.95 times as wide as long (Figs 12A, 13B), with outline of frons less convex. Outline of genae straight or almost so (Fig. 13A). Scape at least with base partly reddish–testaceous (Fig. 13C) ................................................................... 15

15(14′). Notauli broad but hardly impressed, obliterated by sculpture and appearing crenulate (Fig. 12C, D). Temples angulate with occiput (Fig. 12A). Gaster shorter than in alternate, 1.90 times as long as height of third gastral tergite (Fig. 12G). Cleptoparasite of Scambus upon Pissodes validirostris within cones of Pinus spp........... ................................................................................................... Eurytoma annilai Hedqvist, 1974

15′. Notauli narrower than in alternate, appearing as impressed lines, not or little obliterated by sculpture (Fig. 13D). Temples merging with occiput (Fig. 13B). Gaster longer than in alternate, 2.20 times as long as height of third gastral tergite (Fig. 13H). Parasitoid of bark beetles on coniferous trees........................................ .................................................................................................... Eurytoma arctica Thomson, 1876

Known males

1. Metacoxa densely setose dorsally from base (as in Fig. 4N ). Marginal vein somewhat to evidently thickened, 2.90–4.80 times as long as wide (as in Figs 22H, 29D, H). Lower surface of costal cell densely setose (as in Figs 22G, 29A, E). Clypeus emarginate on ventral margin (Fig. 33C, F) or pronotum with cristate sculpture (as in Fig. 14D–F) ...................................................................................................................... 2

1′. Metacoxa bare dorsally at base or marginal vein not thickened, at least 6.0 times as long as wide (as in Figs 12H, 13G, 18J, 25J). Setation of lower surface of costal cell as usual, not especially dense (as in Fig 16H). Clypeus often hardly emarginate (as in Fig. 32C).............................................................................6

2(1). Notauli appearing as complete impressed lines, not obliterated by the sculpture of the mesoscutum (as in Fig. 35A)...................................................................................................................................3

2′. Notauli hardly impressed and/or obliterated by sculpture (as in Figs 14D, 22C) .................................... 5

3(2). Marginal vein shorter and distinctly widening distally, 3.50–4.50 times as long as wide (as in Figs 11G, 29H)...............................................................................................................................................4

3′. Marginal vein less thick than in alternate, 4.85 times as long as wide, and not widened distally (as in Fig. 29D) .................................................................................. Eurytoma melanoneura Walker, 1871

4(3). Marginal vein quite wide, 2.90 times as long as wide (as in Fig. 11G). Wing membrane with diffuse infumation below marginal vein ................................................................... Eurytoma aloisifilippoi (Russo, 1938)

4′. Marginal vein less wide, 3.50–4.50 times as long as wide (as in Fig. 29H). Wing membrane without infumation below marginal vein..................................................................... Eurytoma striolata Ratzeburg, 1848

5(2′). Walls of punctures strongly raised on mesonotum, forming transverse crests on pronotum (as in Fig. 14E, F). Scape with large reticulate surface on inner side (Fig. 14I). Dark species: head, mesosoma, scape, legs, except trochanters and knees, dark to black........................................................ Eurytoma cristata sp. nov.

5′. Walls of punctures raised as usual on mesonotum, not forming crests on pronotum (as in Fig. 22C). Scape with a small and smooth ventral swelling (Fig. 23D). Species extremely variable in coloration: sometimes head, mesosoma, petiole, and legs entirely yellow (Fig. 23A, B); in the darkest forms at least part of scape, a spot on lateral panel of pronotum, and procoxae yellow................................. Eurytoma morio Boheman, 1836

6(1′). Adscrobal carina raised ventrally on mesepisternum and elbowed, delimiting a ventral shelf when seen in lateral view (Fig. 31B). Scape with long but hardly protruding ventral swelling (Fig. 18L)........................ ............................................................................................................. Eurytoma ithma sp. nov.

6′. Adscrobal carina not raised and mesepisternum rounded anteriorly in front of mesocoxae (as in Figs 12F, 13E, 19D, 20D). Scape either with distinct ventral swelling or with very short smooth area....................7

7(6′). Scape with a small apico-ventral swelling (Figs 10D, 21H). Pronotum finely and sparsely punctured, the points rounded and interspaces distinctly coriaceous (as in Fig. 5G). Lower face entirely strigose, the radiating crests long, reaching antennal toruli and lower margin of eyes (as in Figs 10A, 21A)......................................8

7′. Scape with a large ventral swelling, either contrasting in colour with the rest of the surface or strongly promi- nent (Figs 13J, 20I, 34C, 34F) ...................................................................................................... 9

8(7). Head transverse in dorsal and frontal views (as in Fig. 10A). Spots on pronotum extended on lateral panels (as in Fig. 10B). Swelling (= sensillar plate bearing pores visible through integument) of scape subcircular, relatively protruding (Fig. 10D)............................................................. Eurytoma afra Boheman, 1836

8′. Head roundish in frontal view, long and globose in dorsal view (as in Fig. 21A, B). Sensillar plate of scape hardly protruding (Fig. 21H) ............................................................. Eurytoma maura Boheman, 1836

9(7′). Scape reddish with dark, not very prominent swelling (Fig. 26C). F5 symmetric and without apical peduncle (Fig. 26D). Legs reddish, except meso- and metacoxae and the relevant femora, partly fuscus (Fig. 26A). Species associated with gall midges of the genus Rhabdophaga on Salix spp. ........... Eurytoma saliphila sp. nov.

9′. Scape black or nearly so, and quite prominent ventrally (Figs 13J, 20I, 17B, 34C, F). F5 generally strongly asymmetric and with apical peduncle (Figs 13I, 20H, 17A, 34A, 34D). Tibiae and procoxa dark. Parasitoids of seed eaters associated with coniferous trees...............................................................................10

10(9′). All funicular segments strongly asymmetric, nodiform, and with an apical peduncle (Figs 17A, 20H, 34A, D). Scape completely black (Figs 17B, 20I). Larvae seed eaters or parasitoids of seed eaters on coniferous cones .............................................................................................................................................11

10′. F5 symmetric and with very short apical peduncle, other segments elongate and only fairly nodiform (Fig. 13I). Base of scape pale (Fig. 13J). Parasitoid of bark beetles on coniferous trees........................................... .................................................................................................... Eurytoma arctica Thomson, 1876

11(10). Pilosity of forewing white (Fig. 12H). Propodeum with deep and crenulate median channel, the median crest short and irregular. Cleptoparasite of Scambus upon Pissodes validirostris within cones of Pinus spp......... ................................................................................................... Eurytoma annilai Hedqvist, 1974

11′. Pilosity of forewing entirely dark. Propodeum sometimes with superficial median channel and complete median crest (Fig. 20J). Larvae seed eaters..............................................................................................12

12(11′). Median channel of propodeum superficial, but with complete median crest (Fig. 20J). Scape abruptly nar- rowing at apex on ventral margin (Figs 20I, 34C). Larvae phytophagous in seeds of Larix spp. ................. .......................................................................................................... Eurytoma laricis Yano, 1918

12′. Propodeum with deep and crenulate median channel, the median crest short and irregular (Fig. 17C). Scape progressively narrowing at apex on ventral margin (Fig. 17B). Nearctic species introduced in Europe, phytophagous in seeds of Pseudotsuga menziesii ............................................................... Eurytoma gatesi sp. nov.

= Ipideurytoma spessivtsevi Boucˇek & Novicky syn. nov.

Type material

Eurytoma afra . Lectotype designated by Claridge and here validated, with the following labelling ‘afra m ♂ flavimana 93’ (manuscript)/(grey label without writing)/ ‘498 Sm’ (manuscript, for Smoland) (red label)/NRM Stockholm (in NHRC). Decatomidea polygraphi . Type female labelled ‘Morgantown W Va’ (manuscript)/‘type’/ ‘4114’/‘ex Polygraphus rufipennis on spruce’/‘type USNM 2176’ (in USNM). Ipideurytoma spessivtsevi . Type ma- terial not examined but the original description leaves no doubt about the identity of the species, which is so distinctive as to be described in a separate genus.

Remarks

The taxonomy of E. afra is somewhat complicated as the existing type is a male. The original female – not that selected by Thomson, and later examined by Ferrière – certainly belongs to the same species as the male. The original description mentions ‘antennis breviter monoliformibus’ and ‘prothorace utrinque flavomaculato’, which all together are distinct features of

E. afra . Ferrière (1950) erroneously synonymized E. saliciperdae with it. The confusion was later recognized by Graham (1970). Part of the type series of I. spessivtsevi had previously been correctly identified by Erdös as belonging to E. afra (Boucˇek & Novicky, 1954). Zerova (1998) rightly synonymized I. spessivtsevi with Decatomidea polygraphi , but followed Ferrière in the interpretation of E. afra . As an implication of the species name synonymy, Zerova also synonymized Ipideurytoma with Eurytoma . Her suggestion is validated here by our molecular results. Eurytoma afra always appears as the sister group of E. maura with strong support.

The species was well described and illustrated by Boucˇek & Novicky (1954). Because of the shape of the head, especially in the female ( Fig. 10A–C ), it was originally proposed as a new genus.

Hosts

The holotype of Ipideurytoma spessivtsevi was reared from Trypodendron signatum (Fabricius, 1787) ( Curculionidae : Scolytinae ) (Boucˇek & Novicky, 1954). A list was provided by Hedqvist (1963: 47) from initial data published by Jamnický (1957). This list includes Trypodendron lineatum (Olivier, 1795) and Trypodendron domesticum (Linnaeus, 1758) . Eichhorn & Graf (1974) mentioned E. afra as the primary parasitoid of these beetles.

Distribution

The species is widely distributed, being present in the Nearctic and Palaearctic regions. It is from Northern and Central Europe ( Noyes, 2013). The westernmost specimens were collected in the Juliana Alps, close to the Slovenian border (see Appendix S4 and Fig. S 10 in Appendix S8).

Figures

Figure 4. A–O, Eurytoma laricis (D, F, H, I, J); Eurytoma morio (G, M, N); Eurytoma striolata (A, B, C, L, O). A, back of head; B, postgena; C, postoccipital region; D–E, clypeus; F–G, lower face; H, male scape; I, scape plate with pores (arrows); J, male antenna; K, mesoscutum; L, female propodeum; M, procoxa; N, metacoxa; O, female petiole. Abbreviations: ATP, anterior tentorial pits; GC, genal carina; LFP, lateral formaminal plate; PGG, postgenal groove, PGL, postgenal lamina; PTP, posterior tentorial pits.

Figure 10. A–D, Eurytoma afra: A–C, female; D, male. A, head in frontal view; B, head and pronotum in lateral view; C, head and mesosoma in dorsal view; D, antenna.