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BFNA Title: Endogemmaceae |
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XX. ENDOGEMMACEAE Konstantinova, Vilnet
& A. V. Troitsky V. Bakalin 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). |
