Axina Kirby, 1818

Opitz, Weston, 2020, Taxonomic revision of the Western Hemisphere checkered beetle genus Axina Kirby (Coleoptera: Cleridae: Clerinae), Insecta Mundi 2020 (793), pp. 1-70 : 8-12

Genus Axina Kirby, 1818

Axina Kirby, 1818: 389 . Papp 1960: 80. Winkler 1961: 44. Ekis 1975: 19. Opitz 2010: 66; 2014: 3. See Corporaal (1950: 98) for more historical citations.

Type species. Axina analis Kirby, 1918: 392 . By original designation.

Diagnosis. Among the Western Hemisphere genera of Clerinae , Axina specimens are characterized by their serrate antennae ( Fig. 6) and clavate prothoracic femur, two characteristics they share with members of the genus Priocera . However, Axina specimens show a securiform terminal maxillary palpomere ( Fig. 4), whereas in Priocera specimens the terminal maxillary palpomere is digitiform.

Synapotypic characteristics. Phallic plate serrate and presence of spermatophoral gland.

Redescription. Size. Length 5.0–21.0 mm; width 1.2–5.0 mm. Form. Oblong rectangular, body shallow, about 4 times longer than broad. Vestiture. Dorsum profusely vested with short pubescence, antenna ( Fig. 10) sparsely setose, anterodistal angle of antennomeres 4–11 profusely vested with microsensillae, elytra abundantly vested with short 2° setae, all setae emerge from minute punctures. Head. ( Fig. 1) Cranium subquadrate, frons much narrower than width of eye, usually about as wide as length of antennal scape, cranium profusely indented with small setiferous punctures; gula ( Fig. 2) large, trapezoidal, sutures converge, gula with two well-developed setose post-gular processes ( Fig. 2); labrum very shallow, broadly incised distally, tormal processes directed posteriorly, confluent distally, epipharyngeal area very small; mandible, body stout, anterior dens subacute, medial and posterior dens moderately developed, penicillus well developed; maxilla ( Fig. 4), laterolacinia present, terminal palpomere securiform; labium ( Fig. 5), ligula deeply incised, ligular lobes spatulate, terminal palpomere securiform; eyes very large, coarsely facetted, ocular notch deep; antenna ( Fig. 6) comprised of 11 antennomeres, serrate.

Thorax. Pronotum ( Fig. 9) oblong, disc convex and finely punctate, with 2 tumescenses, latter variable in development, disc slightly concave behind tumescences, anterior transverse depression well developed, collar well developed, prointercoxal process expanded distally; pronotal projections ( Fig. 8) short; elytral asetiferous punctures usually small and concentrated in elytral basal half, usually striate near elytral base and near sutural margin, epipleural fold prominent, gradually narrowed to elytral apex, elytral anterior margin not carinate; metathoracic wing, wedge cell closed; metendosternite ( Fig. 7) with furcal lamina, furcal anterior plate large; legs, tibiae with well-developed carina, which is less prominent in metatibiae, prothoracic femora capitate, mesothoracic and metathoracic femora gradually increasing in diameter to femoral apex, tibial spur formula 0-1-1, tarsal sole formula 4-4-4, tarsal formula 5-5-5, unguis without basal denticle. Abdomen. Pygidium transverse/ scutiform; posterior margin of female pygidium sometimes trilobed; male sternite VI elongated, slightly concave at distal margin, distal margin of sternite V often widely emarginate in males; aedeagus well sclerotized, phallobase bilobed, lobe length varies, phallobasic struts usually conjoin at base of phallobasic apodeme, latter rarely present, when present connected to phallobasic struts, phallobasic rod absent; phallic plates narrow, most often serrate to various degree; spicular plates very narrow, spicular apodemes fused in posterior 4⁄5, intraspicular plate narrow/transverse; ovipositor shorter than abdomen, dorsal lamina trilobed, ventral lamina bilobed, laminal rod present. Alimentary canal. Stomodaeum short, proventriculus with 4 primary and 4 secondary lobes, ventral primary and ventrolateral secondary folds reduced; ventricular papillae well defined; 6 cryptonephridial Malpighian tubules; proctodaeum long in females, short in males. Mesodermal male internal reproductive organs. ( Fig. 15–18) Three pairs of accessory glands, medial and lateral glands often broad and recurved, posterior gland very short; testis multifollicular. Mesodermal female internal reproductive organs. ( Fig. 19–20) Spermathecal capsule slightly sclerotized; spermathecal gland attached to middle of spermathecal capsule; bursa copulatrix saccular.

Distribution. From Panama to Argentina.

Key to Species of Axina Kirby

The preparation of this key to species was very difficult because of the paucity of variation in external morphology of Axina species. Many of these nocturnal insects are associated with tree bark and thus have evolved similar bark-like patterns on the elytral disc. In the key that follows, I have used convenient characteristics often involving color characteristics. Whenever possible, the reader should follow up key couplet results with dissections of male genitalia, for reliable species identifications. It is also important that the reader consult the “Variation” section of the species descriptions to recognize exceptions to key couplet descriptions.

The types of two species, Axina cuneata Santos and Filho and A. undata (Spinola) , were not available for study. Thus, they are not included in the following key.

1. Elytral disc with fewer than 50 asetiferous punctures, punctures concentrated in elytral basal half proximal to sutural margin................................................................. 2

— Elytral disc with more than 50 asetiferous punctures, punctures usually extended posteriorly beyond elytral basal half..................................................................... 8

2(1). Prothorax dark castaneous................................................................ 3

— Prothorax testaceous..................................................................... 4

3(2). Each elytral middle with a broad obliquely positioned white fascia ( Peru, Brazil)............................................................... Axina schenklingi Opitz , new species ( Fig. 88)

— Elytral color pattern not as above; elytra with circular testaceous marking in basal ½ ( Brazil)............................................................ Axina bifasciata (Chevrolat) ( Fig. 84)

4(2). Elytral apical region dark brown or black.................................................... 5

— Elytral apical region testaceous............................................................ 6

5(4). Elytral basal ¼ black ( Bolivia)...................... Axina oligocheia Opitz , new species ( Fig. 86)

— Elytral basal ¼ mostly yellow ( French Guiana)............. Axina bella Opitz , new species ( Fig. 83)

6(4). Each elytron with two narrow light brown fasciae, one at middle and one in preapical region; elytral base testaceous ( Brazil, Paraguay)...................... Axina adelosa Opitz , new species ( Fig. 82)

— Each elytron with three dark brown markings................................................ 7

7(6). Elytral prepapical fascia rectangular ( Brazil)............. Axina parcepunctata Schenkling ( Fig. 87)

— Elytral prepapical fascia quadrate ( Brazil)............ Axina macilenta Opitz , new species ( Fig. 85)

8(1). Integument mostly dark brown; elytral color without sharply contrasting colors.................. 9

— Integument not mostly dark brown; elytral color with sharply contrasting colors................. 12

9(8). Cranium black......................................................................... 10

— Cranium not black...................................................................... 11

10(9). Elytral apex black; large species up to 21 mm ( Venezuela).. Axina brunnea Opitz , new species ( Fig. 76)

— Elytral apex testaceous; smaller species up to 11 mm ( Brazil)........ Axina longevittata Pic ( Fig. 77)

11(9). Elytral disc with two faintly expressed yellow oblong lines, one short basal near sutural margin and one spanning elytral length at lateral angular deflection ( Brazil)................................................................................... Axina atmis Opitz , new species ( Fig. 74)

— Elytral disc with faintly expressed brown fasciae ( Brazil)... Axina bahia Opitz , new species ( Fig. 75)

12(8). Elytral apex black....................................................................... 13

— Elytral apex testaceous................................................................... 18

13(12). Elytra broadly testaceous near middle..................................................... 14

— Elytra black near middle................................................................. 17

14(13). Elytral basal region flavotestaceous ( Bolivia).......................... Axina apicalis Pic ( Fig. 92)

— Elytral basal region black................................................................ 15

15(14). Metafemoral distal limit black ( Panama)................. Axina heveli Opitz , new species ( Fig. 96)

— Metafemoral distal ½ black............................................................... 16

16(15). Elytral apex subacuminate ( Bolivia).............. Axina acutipennis Opitz , new species ( Fig. 119)

— Elytral apex obtuse ( Bolivia, Brazil)........................ Axina nigrifrons Schenkling ( Fig. 111)

17(13). Pronotal collar and elytral basal 1/3 testaceous ( Brazil)................................................................................... Axina pallidioccabus Opitz , new species ( Fig. 102)

— Pronotal collar and elytral basal 1/3 black ( Bolivia).......... Axina equestris (Schenkling) ( Fig. 115)

18(12). Body predominantly or entirely flavotestaceous; if bicolorous humerus with black punctiform marking................................................................................... 19

— Body not predominantly flavotestaceous, elytra with variously positioned fascia................. 21

19(18). Elytra unicolorous, testaceous ( Bolivia)................. Axina ochra Opitz , new species ( Fig. 112)

— Elytra bicolorous....................................................................... 20

20(19). Preapical elytral black marking punctiform ( Bolivia, Brazil).... Axina munda Schenkling ( Fig. 100)

— Preapical elytral black marking oblong ( Bolivia).......... Axina vista Opitz , new species ( Fig. 110)

21(18). Abdomen bicolorous, visible sternites I–III dark, IV–VI yellow................................ 22

— Abdomen unicolorous................................................................... 26

22 (21). Base/middle of pronotum with short black streak that extends from pronotum collar to middle depres- sion............................................................................... 23

— Pronotum without black streak........................................................... 25

23(22). Metatibiae testaceous in distal limits ( Brazil).......................... Axina lateralis Pic ( Fig. 98)

— Metatibiae dark in distal limits............................................................ 24

24(23). Elytral preapical brown fascia narrow/angular ( Brazil)..... Axina villa Opitz , new species ( Fig. 109)

— Elytral preapical brown fascia broad/subquadrate ( Brazil).. Axina luzia Opitz , new species ( Fig. 99)

25(22). Metatibiae testaceous in distal limits ( Brazil)........................ Axina analis Kirby ( Fig. 113)

— Metatibiae dark in distal limits ( Argentina).............. Axina pollex Opitz , new species ( Fig. 105)

26(21). Middle of pronotum with dark streak...................................................... 27

— Middle of pronotum without black streak.................................................. 28

27(26). Black pronotum streak extends to pronotum anterior margin ( Brazil).......................................................................... Axina polycaula Opitz , new species ( Fig. 106)

— Black pronotum streak extends from pronotum base to pronotum medial depression ( Brazil)....................................................... Axina ordinis Opitz , new species ( Fig. 117)

28(26). Elytra with clearly defined dark fasciae..................................................... 29

— Elytral dark markings angular, more defused............................................... 39

29(28). Pronotum unicolorous, black or castaneous................................................ 30

— Pronotum bicolorous, black and castaneous................................................ 37 30(29). Pronotum black........................................................................ 31

— Pronotum castaneous................................................................... 34

31(30). Elytron with testaceous spot between broad black fasciae ( Brazil).................................................................................... Axina proxima (Chevrolat) ( Fig. 107)

— Elytral color pattern not as above......................................................... 32

32(31). Elytron mostly black, with two centrally located and conjoined testaceous maculae ( Bolivia and Peru)....................................................... Axina diversesignata Pic ( Fig. 78)

— Elytral color pattern not as above......................................................... 33

33(32). Elytron middle dark fascia traverses sutural margin ( Brazil)................................................................................... Axina latilinea Opitz , new species ( Fig. 90)

— Elytron middle dark fascia does not traverse sutural margin ( Brazil)............................................................................ Axina furcula Opitz , new species ( Fig. 121)

34(30). Cranium black ( Brazil, Argentina)........................ Axina sexmaculata Spinola ( Fig. 123)

— Cranium red-castaneous................................................................. 35

35(34). Midelytral black fascia traverses sutural margin ( Bolivia).............. Axina fortipes Pic ( Fig. 120)

— Midelytral black fascia does not traverse sutural margin...................................... 36

36(35). Midelytral fascia triangular, with posterior margin with indentations ( Brazil)............................................................................ Axina basalis Schenkling ( Fig. 89)

— Midelytral fascia more linear, posterior margin not indented ( Brazil, Argentina).................................................................... Axina spina Opitz , new species ( Fig. 124)

37(29). Cranium castaneous; elytral basal 3/4 with two spheroid yellow maculae ( Bolivia)............................................................. Axina phallospina Opitz , new species ( Fig. 91)

— Cranium black......................................................................... 38

38(37). Prothoracic femur unicolorous, testaceous ( Bolivia, Peru, Brazil)..... Axina fasciata Kirsch ( Fig. 95)

— Prothoracic femur bicolorous, black and testaceous ( Bolivia)................................................................................. Axina megaspina Opitz , new species ( Fig. 122)

39(28). Pronotum unicolorous, red-castaneous.................................................... 40

— Pronotum bicolorous, black and castaneous................................................ 41

40(39). Basal ½ of mostly yellow elytron disc with brown X-marking ( Brazil)............................................................................ Axina chiasta Opitz , new species ( Fig. 94)

— Elytron disc without X-marking, with angular brown fascia at middle ( Brazil)......................................................................... Axina rio Opitz , new species ( Fig. 108)

41(39). Elytral disc without transverse middle fascia................................................ 42

— Elytral disc with transverse, sometimes angular, middle fascia................................. 44

42(41). Basal 3/4of elytron disc with large yellow X-marking ( Brazil)...... Axina picta Schenkling ( Fig. 103)

— Elytral disc without X-marking........................................................... 43

43(42). Elytral disc with longitudinal brown and testaceous streaks ( Bolivia, Brazil)............................................................................. Axina plagiata Schenkling ( Fig. 81)

— Elytron mostly yellow, with brown asetiferous punctures randomly distributed throughout disc ( Brazil)............................................. Axina piperata Opitz , new species ( Fig. 104)

44(41). Basal ½ of mostly brown elytra disc with large yellow circular marking ( Brazil).................................................................... Axina centrimaculata Schenkling ( Fig. 93)

— Elytral disc without circular marking...................................................... 45

45(44). Elytral interstitial spaces minutely cribrate................................................. 46

— Elytral interstitial spaces smooth and very glossy............................................ 47

46(45). Elytral asetiferous punctures substriate, large specimens (up to 20 mm) ( Bolivia, Argentina)....................................................... Axina trinalis Opitz , new species ( Fig. 118) — Elytral asetiferous punctures scattered throughout disc ( Brazil)................................................................................... Axina klisis Opitz , new species ( Fig. 97)

47(45). Pterothorax light castaneous to testaceous ( Brazil)....... Axina minas Opitz , new species ( Fig. 101)

— Pterothorax dark castaneous to black...................................................... 48

48(47). Width of frons wider than length of antennal pedicel........................................ 49

— Width of frons about as long as length of antennal pedicel.................................... 50

49(48). Elytral basal castaneous marking traverses entire basal margin ( Brazil)........................................................................ Axina lobispinula Opitz , new species ( Fig. 79)

— Elytral basal castaneous marking restricted to humeral angle ( Brazil)........................................................................ Axina orcastomata Opitz , new species ( Fig. 80)

50(48). Edge of phallic plate serrate ( Fig. 26); female pygidial distal margin with stalked plate ( Fig. 60) ( Brazil)............................................... Axina ignota Opitz , new species ( Fig. 116)

— Edge of phallic plate not serrate (Fig. 45); female pygidial posterior margin trilobed ( Fig. 58) ( Brazil)..................................................... Axina conspicua Schenkling ( Fig. 114)

Descriptions of Axina Species

bahia species group

There are four species in this group whose members show a brown elytral disc. Geographically, the group is known from Colombia, Venezuela, and Brazil.