Key to the known female Phyllium (Phyllium) ILLIGER, 1798 of the Philippines

1. Alae well-developed; ( celebicum species group).............................................................................................................................2.

- Alae rudimentary; ( siccifolium species group)................................................................................................................................ 3.

2. Abdominal segment VII lateral margin with distinct lobe; angle of exterior lobe of profemora approaching 90 degrees; (Marin- duque, Luzon & Batan) .................................................................................................................... ericoriai HENNEMANN et al.

- Abdominal segment VII lateral margin with indistinct lobe & converging posteriorly; angle of exterior lobe of profemora obtuse; (Northern Luzon) ................................................................................................................................... bonifacioi LIT & EUSEBIO

3. Anal abdominal segment (X) distinctly wider than long, with a broad apex.................................................................................. 4.

- Anal abdominal segment (X) appearing longer than wide, with a narrow apex............................................................................. 6.

4. Subgenital plate with concave sides creating a small fine point that that hardly projects over the posterior margin of abdominal segment IX; (“ Philippines ”) ....................................................................................................................................... .. geryon GRAY

- Subgenital plate margins straight or slightly convex creating a more prominent plate................................................................... 5.

5. Outer margin of exterior lobe of profemora acutely dentate; teeth of interior lobe large and approximately evenly spaced; subgen- ital plate margins straight and gonapophyses not passing the apex of abdominal segment X; (Sibuyan) .......................................... ........................................................................................................................................................................ woodi REHN & REHN

- Outer margin of exterior lobe of profemora relatively smooth; teeth of interior lobe small and paired creating uneven spacing; subgenital plate margins convex and gonapophyses passing over the apex of abdominal segment X; (Mindanao) ......................... ..................................................................................................................................................................................... fallorum n. sp.

6. Antennae with 10 segments............................................................................................................................................................. 7.

- Antennae with 9 segments............................................................................................................................................................... 8.

7. Medium sized species (77.5–88.0 mm); Abdominal segments VII & VIII with widely rounded lobes; 5–7 equally sized/spaced acute teeth on the interior lobe of the profemora; longer subgenital plate almost reaching the apex of the anal abdominal segment; (Northwestern Luzon).............................................................................................................. .. philippinicum HENNEMANN et al.

- Small species (65.0 mm); Abdominal segments VII & VIII with acute lobes extending posteriorly; five unequal, prominent, and