Euodynerus (Euodynerus) dantici ( Rossi, 1790 )

Selis, Marco, Fateryga, Alexander V. & Cilia, Giovanni, 2024, The genus Euodynerus Dalla Torre in Europe and the Maghreb (Hymenoptera: Vespidae: Eumeninae), Zootaxa 5537 (2), pp. 151-194 : 166-169

Euodynerus (Euodynerus) dantici ( Rossi, 1790)

( Figs 6A–O ; 14D ; 15E, H, M, T ; 16E, I )

Vespa dantici Rossi, 1790: 89 , pl. 6, fig. 6, ♀ — “ Italia ” (syntype ZMB [examined]).

Odynerus postscutellatus Lepeletier, 1841: 627 , ♀, ♂ — “ Environs de Paris ” (coll. Lepeletier,? MRSN).

Euodynerus dantici iberogallicus Blüthgen, 1942: 301 , ♀, ♂ — [ France] “ Callian (Dept. Var.)” (ZMB [examined]).

Odynerus dantici var. lagostae Giordani Soika, 1942: 58 , ♂ — “Dalmazia italiana: Lagosta” (? type lost).

Euodynerus espagnoli Vergés Serra, 1965: 105 , figs 1, 3–4, ♂ — “Comarca de Canet de Mar (Barcelona)” (coll. Vergés Serra).

Euodynerus dantici poggii Giordani Soika, 1986: 115 , ♀ — “ Italia: Isola Montecristo , Cala Maestra ” (MSNG). Syn. nov.

Euodynerus minoricensis Sanza in Sanza et al. 2003: 59, 60 (key), figs 9–11, 13–14, 16–17, ♀, ♂ (in subgenus Euodynerus ) — “Mercadal (Cala Pregonda)” (? coll. Sanza). Syn. nov.

Distribution. Trans-Palaearctic taxon, ranging from the Iberian Peninsula in the West to Central Asia and China in the East, descending into the Maghreb and the Levant ( Fateryga et al. 2019; present data).

Notes. Euodynerus dantici is a polytypic species, occurring in the whole Palaearctic and part of the Oriental region with five subspecies in addition to E. dantici s. str. The nominotypical subspecies ( Fig. 6A ) has been widely recorded from most of the Palaearctic region, with the other subspecies replacing or cohabitating with it in some localities: dantici brachytomus (Kostylev) ( Fig. 6F ) in Eastern Siberia and the northern Far East, dantici pamiricus Blüthgen ( Fig. 6E ) in the Pamir Mountains, dantici poggii Giordani Soika ( Fig. 6B ) in Montecristo Island ( Italy), dantici tinctus (Walker) in Egypt, and dantici violaceipennis Giordani Soika ( Fig. 6G ) in East Asia from Japan to Vietnam.All of these subspecies were examined and sequenced, except for E. dantici tinctus for which no specimen was available (we examined the female reported to be in MSNVE by Dal Pos et al. (2022), but it comes from Algeria and belongs to the nominotypical subspecies), revealing a complex situation made of several lineages. E. dantici violaceipennis resulted as the sister-group of all other Euodynerus s. str. considered in this study and does not cluster together with the remaining lineages of E. dantici ( Fig. 2 ), and differs from nominotypical specimens from Italy (the type specimens of E. dantici come from Central Italy) by an average genetic distance of 13.43%, and the average distance progressively increases when compared to the other lineages, reaching up to 38.03% with E. dantici pamiricus from Tajikistan; although similar in pattern and coming from close areas, E. dantici violaceipennis and E. dantici brachytomus differ by an average genetic distance of 20.72%. The other subspecies of E. dantici form a single clade with a bootstrap support of 99 ( Fig. 3 ), but showing high genetic distances between each other, except for a female of E. dantici poggii from Montecristo Island that resulted identical to specimens from continental Italy. The nominotypical subspecies is composed by three lineages with low genetic distances, with specimens from Italy differing from those from Malta, Spain, and Morocco by an average of 2.14%, and from those ranging from Greece to the Far East by an average of 1.71%; the Western and Eastern lineages differ by 3.94%. Two specimens of the subspecies brachytomus, from Eastern Siberia and Japan, were sequenced resulting as the sister-group of the Eastern lineage of E. dantici s. str. and differing from the nominotypical subspecies by an average genetic distance of 7.82%. The remaining two lineages include specimens with ivory markings, the first from the Pamir Mountains in Central Asia and described as E. dantici pamiricus , and the second from Laos ( Fig. 6H ) and never recorded before; the average distances of the Laotian lineage range from 12.86% with the subspecies pamiricus to 25.99% with E. dantici violaceipennis , while E. dantici pamiricus is the most divergent lineage, differing by 24.17% from the nominotypical subspecies, 28.42% from E. dantici brachytomus and 38.03% from E. dantici violaceipennis . These data could indicate the presence of multiple cryptic species currently included under the name of E. dantici , but the scarcity of material for some of the subspecies and the lack of evident morphological differences do not allow us to resolve the taxonomy of this group; genetic techniques more powerful than the simple barcoding could provide useful data. The only taxonomic action that can be confidently taken with the available data regarding the subspecies of E. dantici is the synonymy of E. dantici poggii under the nominotypical subspecies, from which it differs only by the barely darker pattern and does not show the slightest morphological and genetic difference. Given the clear separation from the rest of the subspecies, E. dantici violaceipennis could be elevated to the rank of species but given the lack of evident morphological differences, we defer this decision to future studies that include a larger sample of Asian Euodynerus species.

Euodynerus minoricensis Sanza, 2003 ( Fig. 6D ) was described as a species endemic of Menorca similar to E. dantici but differentiated by few differences in the morphology of clypeus and chromatic pattern ( Sanza et al. 2003). Morphological comparison of E. minoricensis with specimens of E. dantici from the whole range of the species showed how the morphological differences observed in the clypeus fall within the intraspecific variability of E. dantici ( Figs 6I, J ), and the pattern of E. minoricensis is largely variable presenting all the intermediate forms between typical E. dantici and the dark pattern described for E. minoricensis . In addition, DNA barcoding of a male specimen of E. minoricensis produced a sequence that is nested within the E. dantici s. str. clade and shows a genetic distance of just 3.71% when compared with E. dantici from the Western Mediterranean ( Spain, Morocco and Malta) ( Fig. 3 ). Given the absence of substantial differences and the very low genetic distance, much lower than that observed between the subspecies of E. dantici , E. minoricensis is here considered only as an insular form with a slightly darker pattern and therefore synonymized under the nominotypical subspecies of E. dantici . Another similar case in E. dantici is known from the island of Lastovo ( Croatia) and was described as subspecies E. dantici lagostae ( Giordani Soika 1942: 58) , later considered as a case of insular melanism by Gusenleitner (1997: 126).

The orange-marked specimens from Malta ( Figs 6C, M ) reported by Cassar et al. (2022) were sequenced and showed no genetic distance from continental specimens from Spain and Morocco, further confirming their conspecificity with E. dantici .

Giordani Soika (1942) designated as “ neotypes ” of Euodynerus dantici a pair from San Vincenzo , Tuscany, but this designation is invalid as one specimen of the original type series is present in ZMB .

Figures

FIGURE 2. Phylogenetic tree (Neighbor-Joining) of Euodynerus (Euodynerus) based on the mitochondrial COI gene. Ancistrocerus gazella (Panzer) was used as an outgroup. Numbers adjacent to branches represent bootstrap support (values of <75 are omitted); only the species occurring in the considered area are highlighted. Countries are abbreviated using ISO 3166-1 alpha-2 codes. Continues in Fig. 3.

FIGURE 3. Phylogenetic tree (Neighbor-Joining) of Euodynerus (Euodynerus) based on the mitochondrial COI gene. Ancistrocerus gazella (Panzer) was used as an outgroup. Numbers adjacent to branches represent bootstrap support (values of <75 are omitted); only the species occurring in the considered area are highlighted. Countries are abbreviated using ISO 3166-1 alpha-2 codes. Continuation of Fig. 2.

FIGURE 6. Euodynerus dantici (Rossi). A, K, female from Italy (E. dantici s. str.). B, L, female from Montecristo, Italy (E. dantici poggii Giordani Soika, syn. nov.). C, M, female from Malta. D, J, male from Menorca, Spain (E. minoricensis Sanza, syn. nov.). E, female from Tadjikistan (E. dantici pamiricus Blüthgen). F, N, female from Buryatia, Russia (E. dantici brachytomus (Kostylev)). G, O, female from China (E. dantici violaceipennis Giordani Soika). H, female from Laos. I, male from Greece.

FIGURE 14. Male genitalia, from left to right: aedeagus in ventral view, aedeagus in lateral view, digitus+volsella. A, Euodynerus bidentatus (Lepeletier). B, E. caspicus (Morawitz). C, E. curictensis Blüthgen. D, E. dantici (Rossi). E, E. disconotatus (Lichtenstein). F, E. fastidiosus (de Saussure). G, E. hellenicus Blüthgen. H, E. semisaecularis (Dalla Torre). I, E. variegatus (Fabricius). J, E. velutinus Blüthgen. K, E. bidentoides (Giordani Soika). L, E. notatus (Jurine). M, E. posticus (Herrich-Schaeffer). N, E. quadrifasciatus (Fabricius).

FIGURE 15. A–E, S2 in lateral view. F–I, propodeum in posterodorsal view (arrowheads indicating dorsal carinae). J–O, vestiture of mesosoma. P–Q, metanotum in anterior view. R–T, male hind tarsus in dorsal view. U–Y, female head in dorsal view (arrowhead in Y indicating foveae not placed in depression). A, F, J, Euodynerus bidentiformis (Giordani Soika). B, V, E. bidentoides (Giordani Soika). C, K, E. quadrifasciatus (Fabricius). D, E. caspicus (Morawitz). E, H, M, T, E. dantici (Rossi). G, P, S, U, E. posticus (Herrich-Schaeffer). I, Y, E. disconotatus (Lichtenstein). L, R, E. notatus (Jurine). N, E. curictensis Blüthgen. O, E. semisaecularis (Dalla Torre). Q, X, E. fastidiosus (de Saussure). W, E. rubrosignatus Gusenleitner.

FIGURE 16. A–B, male mandible in frontal view (arrowhead indicating normal or modified tooth). C–G, tegula in dorsal view. H–I, apex of T2 in dorsal view (arrowhead indicating lamellar margin). J–K, male hind femur in frontal view (arrowhead in J indicating basal expansion). L–N, apex of male metasoma in lateral view. A, Euodynerus notatus (Jurine). B, E. posticus (Herrich-Schaeffer). C, E. caspicus (Morawitz). D, H, E. hellenicus Blüthgen. E, I, E. dantici (Rossi). F, L, E. fastidiosus (de Saussure). G, N, E. disconotatus (Lichtenstein). J, E. velutinus Blüthgen. K, E. curictensis Blüthgen. M, E. semisaecularis (Dalla Torre).