Cantharis, Linnaeus, 1758

Valenzuela, Enrique & Baena, Manuel, 2024, Cantharis zapatai nom. nov., an overlooked species of Cantharis Linnaeus, 1758 from Central Spain (Coleoptera: Cantharidae), Zootaxa 5432 (1), pp. 121-132 : 130-132

A key to the identification of Cantharis from the Iberian Peninsula

The present key has been prepared to identify the Iberian species of the genus Cantharis and must be considered provisional. Due to the great variability in the colouration in some species, like C. quadripunctata , C. rufa and, especially C. livida (Linnaeus) , with more than 20 colour forms described ( Delkeskamp 1977), the use of the key must be taken with precaution. In the doubtful specimens of these species, the study of the genitalia will be necessary for an accurate identification. For this purpose, the male genitalia of these three species and the 8 th sternite of the female of C. livida are shown ( Figs. 4E, F , 5C, D , and 6C ). Another problem of this key is the separation of the couple C. nevadensis (Pic) / C. instabilis (Kiesenwetter) . Pic (1908) stated that C. nevadensis is close to C. instabilis and may be separated by the colouration. However, the colouration pattern of C. nevadensis fits into the wide variation range of the coloration of C. instabilis . Also, some syntypes of C. instabilis were collected in Sierra Nevada (Granada, Southern Spain), a mountainous region from where C. nevadensis was described and is endemic. Futures studies in progress should elucidate the true taxonomic status of C. nevadensis . Due to the difficult separation of C. pallida (Goeze) and C. cryptica (Ashe) by external features, the male genitalia, male clypeus and the 8 th sternite of the females are included in the key ( Figs. 5A, B, E, F , 6A, B ). We believe, that even with the noted problems, the key can be useful for the identification of the very diverse genus Cantharis from the Iberian Peninsula.

1 Elytra uniformly coloured.............................................................................. 5

- Elytra with several colours.............................................................................. 2

2 Elytra mainly dark coloured, only with a reddish lateral border................................................. 3

- Elytra mainly light coloured with darks parts............................................................... 4

3 Reddish elytral lateral margins extending to basal two-thirds............................................. C. ariasi

- Reddish elytral lateral border extending from humeral angle to apex..................................... C. lateralis

4 Light elytra with a dark sutural longitudinal band................................................... C. pyrenaea

- Light elytra with dark apex..................................................................... C. terminata

5 Elytra light brown, orange, reddish, or yellowish............................................................ 6

- Elytra dark, black or greyish........................................................................... 20

6 Pronotum uniformly coloured........................................................................... 7

- Pronotum with several colours.......................................................................... 15

7 Pronotum totally orange or yellowish..................................................................... 8

- Pronotum black. Antennae and legs completely dark........................................................ 11

8 Hind tibiae with dark zones; length 11–15 mm.............................................................. 9

- Hind tibiae without dark zones; length smaller, 6–11mm..................................................... 11

9 Fore legs and fore tarsi light coloured; elytra without striae.................................... C. livida (ligth form)

- Fore tibiae and fore tarsi dark, elytra with traces of striae..................................................... 10

10 Long antennae, reaching to the elytral apex....................................................... C. antennalis

- Antennae short, not reaching the elytral apex....................................................... C. orgivasa

11 Hind femora slightly dark distally....................................................................... 12

- Hind femora not darkened distally.......................................................... C. rufa (light form)

12 Maxillary palpi with black apex; clypeus of the ♂ semicircular ( Fig. 5F ); aedeagus as the Fig. 5B , 8th sternite of the ♀ as the Fig. 6B ...................................................................................... C . pallida

- Maxillary palpi with light apex; clypeus of the ♂ straight ( Fig. 5E ); aedeagus as the Fig. 5A ; 8th sternite of the ♀ as the Fig. 6A ......................................................................................... C . cryptica

13 Abdomen yellow orange, at least at the apex. Base of each hair, except in the elytra, dark coloured, black, or dark brown. Third antennomere in ♂ wider. Central extensions of 8 th sternite of the ♀ truncated............................... C. palliata

- Abdomen black. Hairs, except in the elytra, white or light brown throughout its length; third antennomere in ♂ less thickened. Central extensions of 8 th sternite of the ♀ rounded.......................................................... 14

14 Length about 12 mm.; pilosity of head, pronotum and legs whitish; elytra very longer, 4,5x the length of pronotum. Central extensions of 8 th sternite of the ♀ in a clearly proximal position with respect to the lateral ones............... C. fresnedai

- Length smaller, about 8 mm; Pilosity of head, pronotum and legs light brown; elytra shorter, 4x the length of the pronotum. Central extensions of 8 th sternite of the ♀ in a distal position with respect to the lateral ones................... C. seidlitzi

15 Pronotum ferruginous with two brown dots........................................................ C. franciana

- Pronotum with a black spot............................................................................ 16

16 Hind tibia whole black................................................................................ 17

- Hind tibiae bicoloured................................................................................ 18

17 Pronotum nearly whole black, only the lateral edges clair. Antennae shorter, not reaching the middle of the elytra................................................................................................... C. brevicornis

- Pronotal black spot smaller, usually not reaching the base. Antennae longer, reaching the middle of the elytra........... 18

18 Pronotum of the ♂ with rounded and poorly marked anterior angles; maximum width of the pronotum towards the middle; aedeagus with parameres shorter than the dorsal plate, this provided with four tips ( Figs 4E, 4F )......... C. quadripunctata

- Pronotum in the ♂ with marked anterior angles; maximum width of the pronotum in the anterior part ( Fig. 3D ); aedeagus with parameres protruding above the dorsal plate, the latter more rounded, without tips ( Figs 4A–C )................ C. zapatai

19 Scutellum light......................................................................... C. rufa (ligth form)

- Scutellum dark...................................................................................... 20

20 Small black spot on pronotum with crown or inverted W shape......................................... C. coronata

- Large, pear-shaped black spot on the pronotum, occupying almost the entire surface....................... C. decipiens

21 Pronotum totally or almost totally black.................................................................. 22

- Pronotum orange with, or without black spot.............................................................. 25

22 Hind tibiae testaceous............................................................... C. flavilabris (dark form)

- Hind tibiae dark (something the proximal part of the hind tibiae of C. paludosa is brownish)......................... 23

23 Small species, 5–6 mm. Lateral border of the pronotum finely edged of reddish brown, some-times not easily visible................................................................................................. C. paludosa

- Species bigger. Whole pronotum black................................................................... 24

24 Species black, body length about 7 mm.............................................................. C. atrata

- Species black except for the mandibles, part of the palpi and first antennomere which are testaceous. Size bigger, 8–10.5 mm.............................................................................................. C. tristis

25 Pronotum orange without spot.......................................................................... 26

- Pronotum orange with some spot........................................................................ 30

26 Scutellum orange............................................................................... C. nigra

- Scutellum black..................................................................................... 27

27 Body length under 10 mm............................................................................. 28

- Body length over 10 mm.............................................................................. 29

28 Hind tibiae and, usually, the hind femora testaceous, smaller species, length, 5.0–7.5 mm................... C. flavilabris

- Hind tibiae black, and hind femora black dorsally; species bigger, length, 9 mm.......................... C. nevadensis

29 Hind femora usually darkened, at least distally; pronotum of semicircular shape with blunt anterior angles................................................................................................... C. livida (dark form)

- Hind femora usually lighter; pronotum less rounded with evident anterior angles.......................... C. pellucida

30 Pronotum orange with small black spots.................................................................. 31

- Pronotum orange with big black spot occupying nearly the whole surface........................................ 36

31 Femora red basally................................................................................... 32

- Femora black....................................................................................... 33

32 Pronotum with three dark spots.................................................................. C. paulinoi

- Pronotum with a cordiform spot................................................................... C. rustica

33 Black pronotal spot reaching the fore border............................................................... 34

- Black pronotal spot not reaching the fore border............................................................ 35

34 Pronotal spot triangular; abdomen orange........................................................... C. reichei

- Pronotal spot rectangular; abdomen black with orange edges.............................................. C. fusca

35 Lenght 11–18 mm............................................................................ C. annularis

- Lenght 7.0–9.3 mm........................................................................... C. instabilis

36 Fore and hind borders of the pronotum black.............................................................. 37

- Fore and hind borders of the pronotum otherwise coloured.................................................... 39

37 Tibiae testaceous............................................................................ C. instabilis

- Whole legs black.................................................................................... 38

38 Second and third antennomeres not thickened. Dorsal plate parallel sided; parameres clearly surpassing the border of dorsal plate....................................................................................... C. obscura

- Second and third antennomeres clearly thickened. Dorsal plate with convergent sides; parameres slightly surpassing the border of dorsal plate............................................................................... C. liburnica

39 Legs completely black........................................................................ C. pulicaria

- Legs partially testaceous............................................................................... 40

40 Length 9–10 mm ........................................................................... C. xanthoporpa

- Length smaller, 7.0– 9.3 mm .................................................................... C. instabilis

Figures

FIGURE 5. Cantharis cryptica, A—aedeagus, ventral view, E—clypeus, ♂; Cantharis pallida, B—aedeagus, ventral view. F—clypeus, ♂; Cantharis rufa, C—aedeagus, ventral view. Cantharis livida, D—aedeagus, ventral view. Scale bars: 0.5 mm.

FIGURE 6. A—Cantharis cryptica, eight abdominal sternite ♀; B—Cantharis pallida, eight abdominal sternite ♀; C— Cantharis livida, eight abdominal sternite ♀. Scale bars: 0.5 mm.

FIGURE4.Cantharis zapatainom.nov.A—aedeagus, ventralview,♂,B—aedeagus,lateral view,♂,C—aedeagus,ventrolateral view, holotype, D—eight abdominal sternite, ♀; Cantharis quadripunctata, E—aedeagus, ventral view, F—aedeagus lateral view. Scale bars: 0.5 mm.

FIGURE3. Cantharis zapatai nom.nov.A—general appearance,dorsal view,male, B—ventral view,♂,C—general appearance, dorsal view, ♀, D—pronotum, dorsal view, ♂, E—pronotum dorsal view, ♀. Scale bars: 1 mm.