Lejeunea gracilipes (Taylor) Spruce, Trans.

Renner, M. A., de, Lange P. J. & Glenny, D. S., 2021, A synopsis of Aotearoa / New Zealand Lejeunea (Lejeuneaceae: Jungermanniopsida) and new species in the Lejeunea epiphylla Colenso complex, Arctoa 30 (2), pp. 187-212 : 202-203

9. Lejeunea gracilipes (Taylor) Spruce, Trans. &

Proc. Bot. Soc. Edinburgh 15: 213. 1884.

Basionym: Omphalanthus gracilipes Taylor, London J. Bot. 5: 385. 1846.

= Taxilejeunea gracilipes (Taylor) Steph., Hedwigia 29: 141. 1890.

= Lejeunea discreta var. gracilipes (Taylor) G.E.Lee & Heinrichs, Phytotaxa 358: 30. 2018.

Original material: Hab. Pacific Isle, Nightingale, Hook. Herb.

Type: Pacific Isles, T . Nightingale ( FH00079615 , G00115757 , NY01059499 )

Lejeunea gracilipes is an Australasian-Oceanian species that is relatively common in the northern third of the North Island and associated islands, with an outlying occurrence on the Chatham Islands. It is often encountered as an epiphyte on nikau trunks. The combination Lejeunea gracilipes (Taylor) Mitt. was published in synonymy of Lejeunea uvifera Mont. , and is therefore invalid (Art. 36.1). The prior existence of an invalid name does not preclude subsequent valid publication of the same combination, so Omphalanthus gracilipes was transferred to Lejeunea by Spruce (1884).

While Lejeunea gracilipes and L. discreta may be closely related, they consistently differ in details of both perianth and lobule morphology, in particular the perianths of L. gracilipes are ecarinate with a short rostrum, whereas those of L. discreta are pentacarinate with a longer, flared rostrum (see Fig. 189 in Lee (2013)). To reflect these differences, and the presence of only one morphotype of consistent expression in New Zealand, we continue to recognise L. gracilipes at species rank, contra Lee et al. (2018).

Lejeunea gracilipes is most often confused with L. flava , as both share a distinctive whitish green living colour, have granular leaf cell surface ornamentation, and are a similar size. When perianths are present distinguishing these two species is straight forward, Lejeunea flava has pentacarinate perianths, while those of L. gracilipes are eplicate. However, L. gracilipes is often found without perianths, which introduces the possibility for confusion. If a search for old perianths buried within the mass of shoots is fruitless, Lejeunea gracilipes and L. flava can be distinguished by differences in underleaf and leaf lobe and lobule size and shape. Lejeunea flava has more ovate underleaves that may be weakly cordate at the base, and may be contiguous or weakly imbricate and almost completely obscure the relatively small lobules; whereas L. gracilipes has more rotund underleaves that are often remote and leave the pyriform lobules visible between sequential underleaves. The leaf lobes of L. flava are ovate to elliptic, and longer than wide and so have outlines that tend to curve more toward their apex whereas those of L. gracilipes are more rotund and evenly curved around their outline.