Ephedra, Linnaeus

Brullo, Salvatore, Brullo, Cristian, Cambria, Salvatore, Ilardi, Vincenzo, Siracusa, Giuseppe, Minissale, Pietro & Galdo, Gianpietro Giusso Del, 2022, Ephedra strongylensis (Ephedraceae), a new species from Aeolian islands (Sicily), Phytotaxa 576 (3), pp. 250-264 : 261

Key to the species of Ephedra genus occurring in Sicily

1. Female cones always biovulate ........................................................................................................................................ E. distachya

- Female cones usually uniovulate........................................................................................................................................................2

2. Twigs 0.4–0.7 in diameter, upper bracts of female cones fused for 1/3–1/2 of its length, female cones 5.0– 5.5 mm long, ripe female cones 5.0–6.0 mm long................................................................................................................................................. E. nebrodensis

- Twigs 0.8–3.5 in diameter, upper bracts of female cones fused for 2/3–7/8 of its length, female cones 5.5–9.0 mm long, ripe female cones 6.0–9.0 mm long.......................................................................................................................................................................3

3. Branches easily disarticulating, smooth or slightly scabrous along the ribs, leaves in whorls of 3 (sometimes opposite), leaves fused for 2/3 of their length, female cones 7.–9.0 mm long, ovule 5.5–6.0 mm long ................................................................... E. fragilis

- Branches hardly disarticulating, more or less scabrous along the ribs, leaves always opposite, leaves 2–3 mm long fused for most of their length, female cones 5.5–7.0 mm long, ovule 4.0– 4.5 mm long...........................................................................................4

4. Twigs 1.5–2.5 mm in diameter, female cones with upper bract 6.0– 6.5 mm long, micropilar tube ca. 2.5 mm long, ripe female strobilus 7.0–8.0 mm long with bracts yellow-gold, seed long-ovoid, 6.0– 6.5 mm long, exserted 0,5– 1 mm from upper bracts ...... ................................................................................................................................................................................................. E.aurea

- Twigs 0.8–1.2 mm in diameter, female cones with upper bract 4.5–5 mm long, micropilar tube ca. 1.5 mm long, ripe female strobilus 6.0–7.0 mm long with bracts pale red, seed ellipsoid, 5.0– 5.5 mm long, exserted 1–2 mm from upper bracts ................... .................................................................................................................................................................................... E. strongylensis