Stenodynerus muelleri ( Dusmet, 1917 )

Selis, Marco, Cilia, Giovanni, Wood, Thomas J. & Soon, Villu, 2024, Taxonomic revision of the Stenodynerus fastidiosissimus species-group in Western Europe and North Africa (Hymenoptera: Vespidae: Eumeninae), Zootaxa 5418 (1), pp. 34-56 : 48-52

Stenodynerus muelleri ( Dusmet, 1917)

( Figs. 4A–B )

Odynerus mülleri Dusmet 1917: 359 , ♀, ♂ (in subgenus Lionotus )—“ Marruecos: Mogador ” (syntypes MNCN).

Stenodynerus gusenleitner i Giordani Soika 1986: 117, fig. 24, ♀— “Marocc o: Marrakech” (holotype female MSNVE). Syn. nov .

Diagnosis. This species can be recognized by the following combination of characters: clypeus as long as wide; apical margin of clypeus more deeply emarginate, emargination 0.3× as deep as wide; gena 0.55× as wide as eye at bottom of ocular sinus, occipital carina highly lamellate in upper half and delimiting a crenate furrow; parategula straight and pointing out, nearly horizontal; lateral carinae of propodeum absent, transition between dorsal and lateral faces entirely rounded; scutellum entirely yellow, T1–T5 with yellow bands. In female: apical teeth of clypeus sharply pointed and carinate, carinae reaching up to middle of clypeus; ocular sinus entirely yellow

Material examined. HOLOTYPE Of STENODYNERUS GUSENLEITNERI : ♀, labeled “leg: J.A.W.Lucas / Marrakech / 29.IV.1982 / MAROCCO // Stenodynerus / spec. nov. // HOLOTYPUS / Stenodynerus / gusenleitneri” ( MSNVE). MOROCCO: Figuig , 950m, 32.24043 -1.27594, 4.VII.2019, leg G.L. Agnoli, 1♀ ( MSVI, OR292151 ) ; Marrakesh-Safi , Imidal 5km S, R203, Tigouramine, 1000m, 31.0737 -8.1362, 7.VII.2022, leg. T.J. Wood, 3♀ (1♀ MSVI, OR292152 , 2♀ TJWC) ; Mogador , XII.1906, leg. Escalera, 1♀ ( MSNVE) ; Mogador, leg. Escalera, 1♂ ( MSNVE).

Distribution. Morocco ( Dusmet 1917; Giordani Soika 1986; Gusenleitner 2004) ( Fig. 6A ).

DNA barcoding. COI-5P gene sequences were obtained from two specimens. The intraspecific sequence divergence of S. muelleri is 0.00%. The species is clearly separated from the other taxa considered in this study and supported by a bootstrap value of 100 ( Fig. 6B ). The lowest interspecific genetic distance exists between S. muelleri and S. fastidiosissimus , with a minimum of 21.85% (mean 23.37%).

Notes. Dusmet (1917) originally described this species comparing it with Odynerus delphinalis Giraud (now Allodynerus delphinalis ) and O. trotzinai Morawitz (now Stenodynerus trotzinai ). It was later moved to Stenodynerus by van der Vecht & Fischer (1972), but Gusenleitner (1981) did not include it in his revision of Palaearctic species, motivating this decision as follows: “ Nicht aufgenommen in die Arbeit wurde die bei van der Vecht und Fischer (1972) zu Stenodynerus gestellte Art muelleri ( Dusmet, 1917) , da die Gattungszugehorigkeit tatsächlich noch nicht geklärt ist. Möglicherweise ist diese Art in die Gattung Allodynerus zu stellen ” [= “The species muelleri ( Dusmet, 1917) , assigned to Stenodynerus by van der Vecht and Fischer (1972), was not included in the work, since the genus affiliation has not yet been clarified. Possibly this species is to be placed in the genus Allodynerus ”]. He did not provide any motivation for which O. muelleri should belong to Allodynerus Blüthgen , but we can speculate that Gusenleitner considered as good the comparison made by Dusmet with Allodynerus delphinalis .

Giordani Soika (1986) described Stenodynerus gusenleitneri as a species similar to S. fastidiosissimus (auct. non de Saussure, 1855) and S. vergesi ,dedicating it to Gusenleitner as a thank you for confirming the species as undescribed. It is evident that both Gusenleitner and Giordani Soika did not examine the type series of Odynerus muelleri , housed in the MNCN. After examination of two syntypes through photographs it became evident that this species does belong to Stenodynerus as already proposed by van der Vecht & Fischer (1972), and it is the senior synonym of S. gusenleitneri , confirmed by examination of the holotype of the latter species ( Fig. 4B ).

Figures

FIGURE 4. A, Stenodynerus muelleri (Dusmet, 1917): habitus of male, habitus of female, head of male, head of female, flagellum of male, aedeagus in ventral and lateral view. B, female holotype of Stenodynerus gusenleitneri Giordani Soika, 1986: habitus in dorsal view and labels. C, Stenodynerus rufescens Giordani Soika, 1977: habitus of male, habitus of female, head of male, head of female, flagellum of male, aedeagus in ventral and lateral view.

FIGURE 6. A, distribution map of the Stenodynerus fastidiosissimus-group in Western Europe and North Africa; records out of the area considered in this study are omitted. B, phylogenetic tree (neighbor-joining) of the Stenodynerus fastidiosissimus-group based on the mitochondrial COI gene. Ancistrocerus gazella (Panzer) and three species belonging to other species-groups of Stenodynerus were used as outgroups. Numbers adjacent to branches represent bootstrap support (values of <75 are omitted).