Galium section Galium

Blanca, Gabriel, Cueto, Miguel, Fuentes, Julián & Ortega-Olivencia, Ana, 2021, Claiming a Boissierian species of Asperula (Rubiaceae), but under a new name: Galium pierredmondii, Phytotaxa 487 (3), pp. 251-262 : 256-257

Key for the Iberian species of Galium section Galium

The following identification key is partially based on Ortega-Olivencia & Devesa (2007), to which the names G. boissierianum , G. moralesianum and G. pierredmondii have been added or conveniently applied.

1. Abaxial side of leaves and bracts with long and swollen epidermal glands near the apex; plants cespitose and pulvinular [ser. Andalusiana Ortega Oliv. & Devesa ] ............................................................................................ G. erythrorrhizon , G. pulvinatum

- Abaxial side of leaves and bracts without long and swollen epidermal glands; plants prostrate, ascending or erect........................2

2. Corolla rotate; partial inflorescences in lax cymes, sometimes contracted and dense, with pedicels 0.7–2.6(4) mm [ser. Galium ]... ............................................................................................................................................ G. verum , G. maritimum , G. tunetanum

- Corolla tubular-infundibuliform, infundibuliform o ± campanulate; partial inflorescences in glomerules or head-like, with flowers sessile to subsessile [ser. Trichogaliopsis (Lange) Ortega Oliv. & Devesa] ......................................................................................3

3. Corolla 3.5–5.8 mm long....................................................................................................................................................................4

- Corolla 1.5–2.6(3.2) mm long ............................................................................................................................................................6

4. Stems slightly scabrid, prickles <0.1 mm long; primary internodes of the lateral branches of the inflorescence up to 70(75) mm; corolla lobes (anthesis) 1–1.3 mm, suberect or erect-patent, oblong-linear; stamen filaments included; mericarps sparsely hirsute to glabrous, with hairs up to 0.2 mm long............................................................................................................... G. boissierianum

- Stems ± tomentose, hairs up to 0.6 mm; primary internodes of the lateral branches of the inflorescence up to 30 mm; corolla lobes (anthesis) 1.5–2 mm, patent, triangular-lanceolate; stamen filaments exerted; mericarps ± densely hirsute, with hairs 0.4–0.7 mm long.....................................................................................................................................................................................................5

5. Leaves strongly scabrid, prickles up to 0.3(0.4) mm long, ± homogeneous........................................................... G. pierredmondii

- Leaves tomentose, hairs 0.05–0.3(0.4) mm long, heterogeneous (mixed in the same leaf), without strong prickles.......................... ................................................................................................................................................................................. G. moralesianum

6. Abaxial side of the leaves white-tomentose, sometimes glabrous or glabrescent in the lower ones ............................... G. baeticum

- Abaxial side of the leaves glabrous or with scabrid nerve ...................................................................................... G. concatenatum