Notosacantha

Borowiec, Lech, Takizawa, Haruo & Świętojańska, Jolanta, 2013, Five new species of Notosacantha Chevrolat (Coleoptera: Chrysomelidae: Cassidinae) from Borneo, with a key to the Bornean species and new faunistic data, Zootaxa 3608 (3), pp. 161-177 : 174-176

Key to Bornean species of Notosacantha

1. Elytral disc with only isolated tubercles, without costae except rudiment of lateral costa.......................... 2

– Elytral disc usually with complete set of costae, or at least with part of dorsal costa.............................. 6

2(1). Large species, length above 5.7 mm, dorsum never mostly black............................................ 3

– Small species, length usually below 5.5 mm, if exceeding 5.8 mm then dorsum mostly black...................... 4

3(2). Elytral marginalia without pale transparent spot in anterior half. Elytral disc yellowish to reddish brown, explanate margin yellowish..................................................................... N. circumdata (Wagener)

– Elytral marginalia with pale transparent spot in anterior half. Elytral disc dark reddish-brown, explanate margin slightly paler reddish brown................................................................ N. moultoni (Spaeth)

4(2). Dorsum mostly black. Lateral costa forms an oblique, elongate fold.......................................... 5

– Eytral disc reddish-brown, explanate margin partly or completely yellow-reddish to reddish. Lateral costa reduced to small tubercle........................................................................ N. clavareaui (Spaeth)

5(4). Explanate margin of elytra black with extreme margin reddish, no pale spots. Frontal plate yellowish-red. Antennae com- pletely yellowish or yellowish with infuscate club..................... N. flaviventris Borowiec & Takizawa sp. nov.

– Explanate margin of elytra completely black or with small, round yellow spot before middle. Frontal plate black. Antennae completely brown to black..................................... N. obscuricornis Borowiec & Takizawa sp. nov.

6(1). Principal tubercle with only two or three branches, anterior and posterior branches of dorsal costa run only from post-basal to apical tubercle or end before apical tubercle, no other costae except oblique rudiment of lateral costa and incomplete apical costa. Large species, length above 7.0 mm......................................................... 7

– Principal tubercle with at least four branches, dorsal and lateral costae complete. Small species, length below 7.0 mm... 8

7(6). Dorsum black, only explanate margin narrowly reddish. Clypeus and antennal club black........ N. nigropicea (Spaeth)

– Elytral disc reddish-brown, explanate margin yellow-reddish. Clypeus yellow, antennal club yellowish-brown..................................................................... N. ovoidea Borowiec & Świçtojańska sp. nov.

8(6). Elytral disc with distinct apical costa................................................................... 9

– Elytral disc without apical costa.................................................... N. fenestralis (Spaeth)

9(8). Anterior and posterior branches of principal tubercle converging at one point. Costa ultima complete or reduced to a small tubercle........................................................................................ 10

– Anterior and posterior branches of principal tubercle not converging at one point, anterior branch connected with principal point more externally than posterior branch. Costa ultima always reduced to a small tubercle..................... 22

10(9). Furca interna complete, connected with lateral costa...................................................... 11

– Furca interna incomplete, ends before lateral costa...................................................... 16

11(10). Principal tubercle moderately high, not higher than its basal width.......................................... 12

– Principal tubercle very high, approximately twice or more higher than its basal width............. N. bryanti (Spaeth)

12(11). Explanate margin of elytra bicolorous, at least in humeral and postero-lateral parts darker than in the middle........ 13

– Explanate margin of elytra unicolorous, yellowish red to reddish........................ N. appropinquans (Spaeth)

13(12). Costa ultima complete............................................................................ 14

– Costa ultima reduced to isolated tubercle.............................................. N. corporaali (Spaeth)

14(13). Explanate margin of elytra yellowish with yellowish brown to brown humeral and postero-lateral spots, occasionally mostly brown with yellow transparent spot before the middle. Elytral disc at least in post-scutellar area yellowish.... 15

– Explanate margin of elytra brownish-black to black with oval, yellow transparent spot before middle; extreme margin yel- lowish. Elytral disc completely black.............................................. N. diabolica Świçtojańska

15(14). Elytral disc mostly black, only basal part between humeral costae yellowish, if yellowish base extends along suture, then reaching at most to base of principal tubercle. Elytral sides slightly more converging posterad..... N. calligera (Spaeth)

– Elytral disc black, basal part between humeral costae and sutural part up to apical tubercle yellowish, sometimes whole area between principal and apical tubercles yellowish. Elytral sides slightly less converging posterad....................................................................... N. flavosuturata Świçtojańska & Takizawa sp. nov.

16(10). Costa ultima reduced to a small tubercle or connected with apical costa by low fold. Body almost rectangular......... 17

– Costa ultima complete, high. Body usually more or less rounded on sides..................................... 18

17(16). Small species, length approximately 4 mm. Anterior part of elytral disc reddish, posterior part black. Apico-lateral costa with completely or partly reduced branches................................................. N. curta (Spaeth)

– Larger species, length 5.6 mm. Elytral disc completely black. Apico-lateral costa with well developed branches................................................................................. N. sarawaiensis Świçtojańska

18(16). Elytral disc predominantly dark, brown to black........................................................ 19

– Elytral disc predominantly pale, yellowish red to reddish, at most tubercles and costae slightly darkened............ 21

19(18). Explanate margin of elytra mostly dark, brown to black................................................... 20

– Explanate margin of elytra uniformly yellowish........................................... N. brookei (Spaeth)

20(19). Small species, length 4.5–5.2 mm. Elytra widest across humerus, distinctly converging posterad. Pronotal disc at top mostly brown. Explanate margin of elytra along border of disc broadly dark brown, without or with very small yellow spot before the middle................................................................... N. quadra (Spaeth)

– Large species, length 5.8–6.2 mm. Elytra more or less regularly rounded on sides. Pronotal disc at top mostly reddish. Explanate margin of elytra mostly dark brown to black, with large yellow spot before the middle............................................................................................ N. kinabaluensis Świçtojańska

21(18). Larger, length 6.8–7.3 mm. Explanate margin of elytra reddish with more or less distinct paler, yellow spot before the mid- dle. Elytral tubercles very low, never marked with black.................................... N. excelsa (Spaeth)

– Smaller, length 5.5–6.5 mm. Explanate margin of elytra uniformly yellowish to reddish. Elytral tubercles higher, espe- cially basal and principal tubercles conical in profile, often top of tubercles marked with black............................................................................................... N. rufa sarawacensis (Spaeth)

22(9). Larger species, length approximately 5 mm ............................................................ 23

– Smaller species, length below 4.6 mm ................................................................ 24

23(22). Elytral tubercles low but well marked on elytral profile. Elytral and pronotal discs uniformly reddish brown, explanate margin reddish.................................................... N. sabahensis Borowiec & Świçtojańska

– Elytral disc only with costae, without tubercles. Dorsum distinctly bicolorous, pronotal disc brown and explanate margin of pronotum yellow, elytral disc with top reddish and sides mostly brownish-black..... N. sandakanensis Świçtojańska

24(22). Explanate margin of pronotum and elytra uniform red with slightly paler extreme margins..................................................................................... N. minuta Świçtojańska & Takizawa sp. nov.

– Explanate margin of pronotum and elytra distinctly bicolorous. Pronotal marginalia yellow anteriorly and brownish basally, elytral marginalia brown with large yellow, transparent spot in the middle................ N. weyersi (Spaeth)