Key to species of Xanthempis from the Mediterranean basin

1 Eyes appressed to ocellar triangle; frons narrow, on upper part at most as broad as distance between outer margins of posterior ocelli............................................................................................... 2

- Eyes separated from ocellar triangle by more or less broad space; frons broad, much broader than distance between outer margins of posterior ocelli.................................................................................. 3

2 Thorax with postpronotal lobes yellow. Epandrium lamellae spherical, strongly concave and voluminous (Daugeron 2000: 386, fig. 16) (East Mediterranean)...................................................... E. (X.) testiculata Bezzi

- Thorax with postpronotal lobes greyish to brownish. Epandrium lamellae narrow, simple (Daugeron 1997: 160, fig. 4). Female unknown (Morocco).............................................................. E. (X.) ifranensis Daugeron

3 Thorax grey or blackish brown........................................................................... 4

- Thorax extensively yellow, at least on pleura................................................................ 9

4 Thorax blackish brown, abdomen entirely brown; fore femur brown dorsally and yellow ventrally (South France)................................................................................... E. (X.) fusca Daugeron et Lefebvre

- Thorax grey, abdomen yellowish to brownish yellow; fore femur yellowish........................................ 5

5 Scutum (dorsal view) with 1 or 2 brownish vittae............................................................ 6

- Scutum (dorsal view) with 3 or 4 brownish vittae............................................................ 8

6 Scutum with 1 very narrow median vitta (Morocco)....................................... E. (X.) edithae Daugeron

- Scutum with 2 narrow vittae running along rows of dorsocentral setae............................................ 7

7 Notopleuron with 2 strong setae. Male: epandrial lamellae rounded apically (Daugeron 2000: 383, fig. 14) (south of West Palaearctic)...................................................................... E. (X.) semicinerea Loew

- Notopleuron with 3 strong setae. Male: epandrial lamellae truncate apically (Daugeron 2000: 378, fig. 7). Female unknown (South France)........................................................... E. (X.) pseudosemicinerea Daugeron

8 Scutum with 4 vittae: 2 median vittae between rows of dorsocentral setae and 2 lateral vittae between dorsocentrals and notopleuron (Spain)................................................................. E. (X.) caceresensis Daugeron

- Scutum with 3 vittae, median vitta somewhat narrower (Spain)........................ E. (X.) moncayoensis Daugeron

9 Scutum entirely yellow................................................................................ 10

- Scutum with brown to black pattern, sometimes almost entirely greyish to blackish................................ 16

10 Postsutural supra-alar seta present....................................................................... 11

- Postsutural supra-alar seta absent........................................................................ 13

11 Dorsocentral setae irregularly biserial at least on middle part of scutum, more numerous in female. Female: acrostichal setae present (Europe)...................................................................... E. (X.) lutea Meigen

- Dorsocentral setae uniserial throughout; acrostichal setae absent in both sexes.................................... 12

12 Antennae with scape and pedicel brownish; occiput with 1 blackish-brown spot on upper part. Male: phallus pointed at tip (Daugeron 2000: 377, fig. 6) (France)............................................... E. (X.) montivaga Daugeron

- Antennae with scape and pedicel yellowish; occiput with pair of subrectangular blackish spots on upper part. Male: phallus truncate at tip (Daugeron 2009: 61, fig. 1) (France)......................................... E. (X.) fagina Daugeron

13 Antennae with scape and pedicel yellowish (Spain)....................................... E. (X.) nevadensis Chvála

- Antennae black to brown (sometimes scape and pedicel slightly paler than postpedicel)............................. 14

14 Occiput uniformly yellow to reddish yellow (Italy)........................................ E. (X.) lagoensis Chvála

- Occiput largely brownish to black on upper part............................................................ 15

15 Occiput yellow on narrow strip just above neck (Europe).................................... E. (X.) concolor Verrall

- Occiput entirely blackish on upper part (Spain)........................................ E. (X.) algecirasensis Strobl

16 Scutum with dark vittae on greyish or brownish grey background, usually extensively grey to brownish grey............ 17

- Scutum with dark vittae on yellow background, usually extensively yellow....................................... 21

17 Scutum (dorsal view) with 4 blackish vittae: 2 median narrow vittae between rows of dorsocentral setae and 2 broader vittae between dorsocentrals and notopleuron (Europe).......................................... E. (X.) testacea Fabricius

- Scutum (dorsal view) with 1 or 2 brownish to blackish vittae.................................................. 18

18 Scutum (dorsal view) with 1 median vitta. Male: hypandrium with 1–4 long setae on lateral margin................... 19

- Scutum (dorsal view) with 2 vittae running along rows of dorsocentral setae. Male: hypandrium without setae on lateral margin................................................................................................... 20

19 Scutum with 1 very narrow median vitta (Morocco)....................................... E. (X.) edithae Daugeron

- Scutum with 1 broad median vitta occupying almost whole space between rows of dorsocentral setae (Morocco)........................................................................................... E. (X.) chopardi Daugeron

20 Thoracic setation very reduced, dorsocentral setae minute, postsutural supra-alar seta absent (Europe)................................................................................................... E. (X.) digramma Meigen

- Thoracic setation prominent, dorsocentral setae distinct, postsutural supra-alar seta present (Spain).... E. (X.) dispina Chvála

21 Scutum with median vitta between rows of dorsocentral setae and additional vitta or pair of spots between dorsocentrals and notopleuron......................................................................................... 22

- Scutum only with median vitta.......................................................................... 23

22 Scutum usually with pair of brownish to black spots between dorsocentrals and notopleuron. Male: hypandrium without setae on lateral margin (Daugeron 2009: 62, fig. 2) (France)................................... E. (X.) virgulata Daugeron

- Scutum with black vitta between dorsocentrals and notopleuron. Male: hypandrium with 2–4 long setae on lateral margin (Bahid et al. 2018: 121, fig. 1) (Morocco).............................. E. (X.) widanensis Bahid, Kettani et Daugeron

23 Scutal vitta broad, comprising dorsocentral setae. Abdominal setation pale....................................... 24

- Scutal vitta narrow, its width on middle part at most 1/3 of distance between rows of dorsocentrals. Abdominal setation usually black (except E. matilei)............................................................................... 25

24 Abdominal tergites with subtriangular brownish spots dorsally (except tergites 1 and 2). Male: hypandrium rounded apically (Daugeron 2000: 374, fig. 3) (France).............................................. E. (X.) hypandrialis Daugeron

- Abdominal tergites with subrectangular brownish spots dorsally forming subequally broad vitta. Male: hypandrium pointed apically (Daugeron 2000: 382, fig. 13) (South Europe).......................................... E. (X.) laeta Loew

25 Postsutural supra-alar seta present. Prothoracic spiracle yellow................................................. 26

- Postsutural supra-alar seta absent. Prothoracic spiracle brown to black........................................... 28

26 Abdomen covered with yellowish setae. Male: hypandrium bare. Female: acrostichals present (Italy)......................................................................................... E. (X.) matilei Daugeron et Charbonnel

- Abdomen covered with black setae. Male: hypandrium at least with 2 spine-like subapical setae. Female: acrostichals absent (unknown in E. siciliensis)............................................................................. 27

27 Male: hypandrium with 2 spine-like subapical setae. Female unknown (Italy [Sicily]).......... E. (X.) siciliensis Shamshev

- Male: hypandrium with numerous thin subapical setae (Turkey)............................ E. (X.) adanaensis sp. nov.

28 Occiput uniformly brownish on upper part. Male: hypandrium with 7 long setae on lateral margin (France [Corsica]).......................................................................................... E. (X.) kuntzei Becker

- Occiput with distinct rhomboid black spot on upper part. Male: hypandrium without setae on lateral margin............. 29

29 Male: epandrial lamellae concave above; phallus bent beyond middle, short apical part as stout as basal part (Chvála 1994: 162, fig. 285). Female: fore tibia covered with uniform setulae dorsally (throughout Palaearctic)..... E. (X.) stercorea Linné

- Male: epandrial lamellae convex above; phallus bent at middle, basal part with swelling, apical part as long as, but much more slender than, basal part (Chvála 1994: 163, fig. 287). Female: fore tibia, usually, with 1 or 2 small black setae dorsally (Europe).................................................................................... E. (X.) aemula Loew