Nepenthes alata, sensu Danser, 1928

Cheek, M. & Jebb, M., 2014, Expansion of the Nepenthes alata group (Nepenthaceae), Philippines, and descriptions of three new species, Blumea 59 (2), pp. 144-154 : 145-147

KEY TO THE SPECIES OF THE NEPENTHES ALATA GROUP

(updated from Cheek & Jebb 2013h)

1. Lower surface of lid, including convex appendage (if developed), densely and evenly covered by uniformly minute, circular nectar glands (0.15–0.2 mm diam)......... 2

1. Lower surface of lid with nectar glands either absent from the appendage (if developed), and/or sparse, large or dimorphic, (larger glands 0.35–0.4 mm diam or larger). — Visayas and Mindanao....................... 5

2. Stems angular; convex basal appendage absent from lid; male pedicels 3.5–4.5 mm long. — Sibuyan Island.......................................... N. armin

2. Stems terete; convex basal appendage conspicuous from lid; male pedicels> 10 mm long.................. 3

3. Stems glabrous, rarely glabrescent; upper pitcher lacking fringed wings; outer surface <20 % covered with red stellate hairs or lacking them entirely................. 4

3. Stems persistently pubescent; upper pitchers with fringed wings in upper part; outer pitcher surface> 50 % covered with grey stellate hairs. — Northern Luzon..... N. alata

4. Upper pitchers subcylindrical, outer surface 10–15 % covered with minute red stellate hairs. — Lowland coastal ultramafic scrub of N and E Luzon........... N. ultra

4. Upper pitchers with ellipsoid base constricted abruptly to the narrow, cylindrical upper 2/3; outer pitcher surface lacking stellate hairs. — Lowland to submontane forest or scrub of southern Luzon to Mindanao.... N. graciliflora

5. Stems winged from the decurrent petiole bases. — S Mindanao, Sarangani Province ......... N. saranganiensis

5. Stems terete, or angular, lacking wings............. 6

6. Upper pitchers widest at apex.................... 7

6. Upper pitchers subcylindric, widest at base, or equally wide at base and apex.............................. 8

7. Stems and abaxial surface of midrib moderately densely covered with white appressed hairs 0.5–1.5 mm long; lid of upper pitchers ovate, longer than broad. Volcanic substrate. — Mts Apo and Matutum, Mindanao...... N. copelandii

7. Stems and leaf blades glabrous; lid of upper pitcher broader than long. Ultramafic substrate. — Mt Kiamo, Mindanao..................................... N. ceciliae

8. Petioles appearing cylindrical (wings incurved)...... 16

8. Petioles appearing flat, at least distally (wings held flat). 9

9. Stems and lower surface of midrib conspicuously long and densely pubescent; lid appendage well-developed, hook- ed........................................ 10

9. Stems and upper surface of midrib glabrous or inconspicu- ously and shortly and sparsely pubescent-puberulent; lid appendage usually only moderately developed, never hooked ........................................... 12

10. Upper pitchers equally wide at base and apex, contracting slightly at the middle, lacking fringed wings. — NE Mindanao.................................. N. ramos

10. Upper pitchers widest at base, contracting slightly above into a narrower cylinder with a short pair of fringed wings near the mouth.............................. 11

11. Leaf blades long, over 21 cm in length, midrib of lid with numerous more or less circular glands 0.15–0.40 mm diam. — Negros and Biliran Islands........ N. negros

11. Leaf blades of climbing stems short, less than 18 cm in length, nectar glands more or less absent from distal half of lid midrib, glands larger 0.5–0.6(–0.7) mm. — NE Mindanao............................... N. zygon

12. Lid apex with pocket. — S Cotabato, S Mindanao............................................ N. tboli

12. Lid apex lacking pocket or any appendage......... 13

13. Petiole canaliculate proximally (flat distally); blade hairy on upper surface............................... 14

13. Petiole flat proximally; blade glabrous on upper surface. ........................................... 15

14. Upper pitchers stout, length: breadth ratio 2–2.5: 1; fring- ed wings absent. — Mt Hamiguitan, SE Mindanao................................... N. hamiguitanensis

14. Upper pitchers slender, length: breadth ratio> 3: 1; fring- ed wings present below peristome. — NE Mindanao........................................ N. zygon

15. Stems terete; upper pitcher with lid about half as long as mouth; mouth not concave but flat; column absent; lid base truncate. — Mt Malindang, NW Mindanao..... N. kurata

15. Stems angular; upper pitcher with lid about as long as mouth; mouth highly concave; column present; lid base cordate. — Kitanglad Mts , Central Mindanao N. kitanglad

16. Leaf-blade length: breadth about 1: 1, apex deeply and broadly notched.............................. 17

16. Leaf-blade length: breadth about 4: 1, apex acute or obtuse....................................... 18

17. Largest pitchers with fringed wings from base to apex; peristome broad and flat at rear; lid nectar glands restricted to a dome-like area around the basal appendage. — E Mindanao............................. N. robcantleyi

17. Largest pitchers without fringed wings; peristome outer edge rounded at rear; lid nectar glands scattered over lid; dome-like area absent. — NE and Central Mindanao....................................... N. truncata

18. Largest pitchers robust, 18–24 cm long; peristome 7–8 mm wide, curved in section but not cylindric; inner edge of peristome with small teeth visible, outer edge lobed. 19

18. Largest pitchers 12 cm long; peristome 2–3 mm wide, narrowly cylindrical, inner edge lacking visible teeth (unless dissected), outer edge not lobed. — Leyte ..... N. leyte

19. Largest pitchers without fringed wings; leaf midrib densely, minutely white stellate-hairy; pitcher lid base deeply cordate. — NE Mindanao.................. N. extincta

19. Largest pitchers with fringed wings; leaf midrib with brown black bristle hairs 1–1.5 mm long; pitcher lid base truncate. — N and NE Mindanao............ N. mindanaoensis