BFNA Title: Endogemmaceae
XX. ENDOGEMMACEAE Konstantinova, Vilnet & A. V. Troitsky
Plants forming mats. Branches replacing ventral half of a leaf; without flagella. Leaves alternate, succubous, plane or weakly concave, simple, entire. Underleaves absent. Rhizoids scattered over ventral stem. Specialized asexual reproduction by 1-celled gemmae formed within swollen apex of stem. Gynoecium terminal on an ordinary leafy branch. Perianth present, well-developed, projecting beyond bracts, with subfloral branches, perianth cylindric, usually somewhat plicate distally, mouth narrow, perigynium absent.
Genera 1, species 1; North America, Eurasia.
The family name is based on a feminine noun of Latin origin (i.e., "gemma"), so the name must be corrected to Endogemmaceae following Article 18.4 of the Code (pers. comm. P. M. Eckel).
1. ENDOGEMMA Konstantinova, Vilnet & A. V. Troitsky, Folia Cryptog. Estonica 48: 132. 2011 * [Greek endo, inside, and gemma, bud, alluding to the endogenous gemmae]
Leaves obliquely inserted, unlobed, rounded, cells large, pellucid, leptodermous, trigones absent. Oil bodies one per cell, very large, almost smooth. Gemmae endogenously formed, rounded quadrate with a single glistening oil-body. Sexual condition dioicous. Perianth present, without perigynium or shoot calyptra, 0.5–0.65 emergent, 4--5-plicate in at least the distal part with a small tubular beak.
Species 1: North America, Eurasia.
Morphologically Endogemma caespiticia is distinctive. A. A. Vilnet et al. (2011) pointed out that features characteristic of both Jungermannia and Solenostoma are found in this taxon. It has the beaked perianth mouth of Solenostoma and a lack of perigynium and shoot calyptra as in Jungermannia s. str. It differs from similar Solenostomataceae and Jungermanniaceae species in having endogenous gemmae and in a characteristic large, single oil-body otherwise only known for S. tetragonum (Lindenberg) R. M. Schuster.
SELECTED REFERENCE Vilnet, A. A., N. A. Konstantinova and A. V. Troitsky. 2011. Taxonomical rearrangements of Solenostomataceae (Marchantiophyta) with description of a new family Endogemmataceae based on trnL-F cpDNA analysis. Folia Cryptog. Estonica 48: 125--133.
1. Endogemma caespiticia (Lindenberg) Vilnet, Konstantinova, Vilnet & A. V. Troitsky, Folia Cryptog. Estonica 48: 132. 2011
Jungermannia caespiticia Lindenberg, Nova Acta Phys.-Med. Acad. Caes. Leop.-Carol. Nat. Cur. 14(Suppl.): 67. 1829; Solenostoma caespiticium (Lindenberg) Stephani
Plants 0.5--1.1 mm, ca. 2--3(--5) mm x up to 1.5 mm wide (near perianth), creeping to ascending, some-times with ventral small-leaved etiolated innovations, pale brownish, white, whitish green and whitish greenish with dirty brownish and brown tint near gemmiparous apices and sometimes reddish perianth beaks. Stem (150--)200--300 \um wide, branching lateral, mainly below gemmae tips or perianths, dorsal surface cells thin-walled, with indistinct trigones, (47--)70--240 x 28--50 \um. Rhizoids dense to scattered, colorless to brownish, in indistinct fascicles. Leaves distant to sub-incumbent, inserted at angle of 30--70° with axis in proximal part of stem to (distally and near perianth) 70--80°, dorsally not decurrent or decurrent up 1/6 of stem width (evident only in large plants), ventrally subtransversely inserted, not decurrent, 300--765 x (315--)500--1000 \um, 1:0.6--0.7(--0.9), transversely oval, flattened to slightly concave and loosely channeled, sometimes with undulate margin; cells in the midleaf thin-walled, from (rarely) 28 x 28 \um to 47--90 x 42--65 \um, trigones indistinct to very small and concave, near margin (30--)40--70(--100) \um, thin-walled, but sometimes with thickened external wall, trigones concave, cuticle smooth everywhere. Specialized asexual reproduction by orbicular to oval to irregularly tetragonal (in projection) gemmae, 8.4--14(--18) x7--10(--14) \um. Perianth emergent for 3/4 of its length, fusiform to cylindric, 5-plicate (1-dorsal, 2-lateral and 2-ventral), 1000--1850 x 400--1000 \um (small ones sterile and filled by gemmae). Capsule 280--300 \um in length. Elaters 140--170 x 8.4 \um, 2-spiral. Spores finely papillose, 11.2--15.4 \um.
On soil near stream, field banks, clayey roadsides; 0--500 m; B.C.; Quebec; Alaska, N.Y.; Eurasia (including Russian Far East and Siberia).