Prosopanche, de Bary, 1868

Tavares De Carvalho, Jordano D., Markus, Catarine, Junior, Aldo Merotto, Záchia, Renato A., Schuch, Marilia, Sulzbach, Estéfani & Mariath, Jorge E. A., 2021, Prosopanche cocuccii (Hydnoraceae): a new species from Southern Brazil, Phytotaxa 521 (3), pp. 177-192 : 189-190

Key to species of Prosopanche

1. Staminodes cucullate, perigonial tube extending above the synandrium insertion....... P. panguanensis C.Martel & Rob.Fernandez

- Staminodes bilobed, perigonial tube not extending above the synandrium insertion ........................................................................2

2. Rhizome (4–)5(–6)-gonous ................................................................................................................................................................3

- Rhizome 3(–4)-gonous .......................................................................................................................................................................4

3. Flowers solitary; rhizome (4–)5(–6)-gonous; synandrium 30–40 × 23–25 mm; tepals 60–70 × 30–50 mm; South America ............ ................................................................................................................................................................ P. americana (R.Br.) Baillon

- Flowers in fascicles; rhizome (4–)5-gonous; synandrium 19–26 × 11–16 mm; tepals 32–56 × 24–36 mm; Costa Rica.................... ....................................................................................................................... Prosopanche costaricensis L.D. Gómez & Gómez-L.

4. Anthers with 3–8 thecae; synandrium 5–9.5 × 3–5 mm; tepals 15–22 × 5–14 mm ...........................................................................5

- Anthers with 9–30 thecae; synandrium 12–20 × 6–16 mm; tepals 35–60 × 9–25 mm ......................................................................6

5. Anthers with 5–8 thecae; synandrium 9–9.5 × 4–5 mm; perigonial tube 5–10 mm long .................................................................... ....................................................................................................................................... P. caatingicola R.F.Machado & L.P.Queiroz

- Anthers with 3–4 thecae, synandrium 5–6 × 3–4 mm; perigonial tube 36–85 mm long ................................ P. demogorgoni Funez

6. Flowers solitary; rhizome often unbranched; ovary 15–20 × 10–20 mm; anthers with 15–30 thecae, staminodes short-pedunculate; 4–10 folds per stigmatic lamella; seeds spheroidal, ca. 0.5 mm wide........................................................... P. bonacinae Spegazzini

- Flower often in fascicles; rhizome often many-branched; ovary 25–70 × 23–34 mm; anthers with 9–13 thecae; staminodes sessile, reflexed; 10–30 folds per stigmatic lamella; seed ovoid, 0.5–0.8 mm wide........................................................................................ ............................................................................................................................ P. cocuccii Tavares de Carvalho, Záchia & Mariath