Schistochila integerrima Steph.

Thouvenot, Louis, 2021, Schistochila gradsteinii sp. nov., a new species from New Caledonia related to S. vitreocincta (Schistochilaceae, Marchantiophyta), with a key to the local species and a description of the gynoecium of S. integerrima, Cryptogamie, Bryologie 20 (2), pp. 11-18 : 12-13

Schistochila integerrima Steph.

Species Hepaticarum 6: 492 (1924).

SPECIMEN EXAMINED. — New Caledonia. North Province, Poindimié, Amoa valley, trail to Goro Até Mèkébo, on trunks in cloud forest, 724 m, 12.X.2019, Thouvenot NC2825 (PC[PC0712101]).

COMMENTS

Among the Schistochila species lacking underleaves (formerly regarded as Gottschea Nees ex Mont. ) and with entire margined leaves, S. integerrima is easily distinguished from species with subequal lobes and inflated keels (see below) by the insertion of the dorsal lobes on the dorsal face of the ventral ones. On the other hand, it is less easy to distinguish from S. neesii (Mont.) Lindb. (Mascaregnes) or S. nuda Horik. (Asia) from which it differs only by larger leaves (leaves 5-6 mm long vs 3-4 mm long) and the total absence of teeth at the leaf apex which are unevenly present in the former species. As hypothesized by So (2003b), further studies involving molecular methods and more material would likely show these species and S. integerrima to be conspecific.

In the diagnosis, Stephani does not describe the gametangia of S. integerrima and So (2003b) states that the plant is known only in sterile condition. Here we provide a description of fertile shoots with unfertilized gynoecia. Androecia remain unknown.

DESCRIPTION OF A FEMALE BRANCH ( Fig. 1 )

A series of underleaves present on fertile shoots just below the gynoecia, the underleaves all deeply and unevenly bilobate with acute lobes, the outermost underleaves divided half-way to the base with margins indistinctly toothed, the innermost underleaves more deeply divided, the lobes tube-like and laciniate. Fertile innovations frequent so that gynoecia are usually in several levels situated one above the other, separated by a few normal leaves with underleaves present or absent; leaves just below the gynoecium progressively modified into bracts, the outermost ciliate only at the base, the innermost leaves 3.5-4.5 mm long, heavily laciniate, connate at base,

linked together in a fringed involucre surrounding linear to furcate scales and many archegonia, ventral lobes canaliculate to involute with margins undulate and apices rounded, dorsal lobes linear, involute.

Figures

FIG. 1. — Schistochila integerrima Steph.: A, cluster of archegonia surrounded by scales, bract involucre and bracts (longitudinal section); B, C, bracts; D, bracteole; E, top of fertile shoot with gynoecium and fertile innovation; F, gynoecium (top view). From Thouvenot NC2825. Scale bars: 1 mm.