The definition of Hypnaceae has become even more confusing due to the recent work of Ignatova and Ignatova (2004), who restricted Hypnum to H. In this work, we used the more traditional definition of Hypnaceae with minimal exceptions.
Ctenidium (Schimp.) Mitt
Bracts smaller than stem leaves, erect-spreading to square-rose, obscurely homogenous to falcon-second, lanceolate to ovate-lanceolate, gradually acuminate, concave, subplicate, short-decurrent; margins toothed to sinuous above, subentire to toothed below, shallowly recurved; costa short and double or none; cells linear to oblong-linear, conspicuously prorulose at upper and sometimes lower ends on abaxial leaf surface, firm-walled, becoming shorter in a few rows across the insertion; alar cells subquadrate to short-rectangular. Perichaetia large, leaves oblong, long acuminate, plicate; margins subentire, shallow; usually no cost; cells linear-flexuous, smooth, becoming laxly rectangular after the insertion; alarm cells not differentiated.
Herzogiella Broth
The plants are autoechoic and the sporophytes are characterized by very thin, long, erect capsules tapering at the neck and contracted below the mouth when dry. The species here is considered a synonym of Herzogiella cylindricarpa, although the lectotype has capsules that are much shorter (1.5–2.0 mm) than those in most other Latin American collections of H .
Homomallium (Schimp.) Loeske
Homomallium mexicanum
Homomallium sharpii
The senior author (Ireland, 1984) placed this species, originally described by Bartram (1946) as Isopterygium, in the genus Taxiphyllum because it has foliose pseudoparaphyllia, a julaceous habit, and a large number of square to rectangular alar cells on the leaf edges. Buck later stated that he was not convinced that the plant belongs to the genus because it is "a much softer plant with more or less pleated leaves and shorter acumina." However, because the senior author (Ireland, 1984) put it in the has included synonyms.
Isopterygiopsis Z. Iwats
Distribution: The genus Isopterygiopsis has only three species in the world, two of which are in Latin America. Isopterygiopsis is now distinguished by its small, scarcely branched, glabrous plants; large to small hyalodermis cells; papillose rhizoids in leaf axils; absence of pseudoparaphilia; sessile, entire or finely toothed leaves; 2–6 celled, smooth, cylindrical or spindle-shaped outgrowths in groups in leaf axils;.
Isopterygiopsis muelleriana
Stems complanate-leaved, appearing ventrally concave due to curvature of upturned leaves; leaves often abruptly acuminate, cells glabrous or dorsally prorulose. In addition, the plants are dioecious and sometimes have smooth, cylindrical or fusiform brood bodies gathered in leaf axils on stems and branches.
Isopterygiopsis pulchella
Asexual reproductive bodies, 30–60 μm long, rarely present, cylindrical or spindle-shaped, aggregated in leaf axils on stems and branches, green to yellowish green, composed of 2–5 smooth cells. 47–122 μm) and narrow (5–7 μm), smooth median leaf cells, alar regions undifferentiated or sometimes with 1–3 short rectangular to square cells at the margins, occasional presence of cylindrical to fusiform, 2–5-celled nestling bodies, united in the axils of the leaves and autosexual state.
Isopterygium Mitt
Mitten placed his new genus in the tribe Stereodonteae on the basis of its long setae, short, bilobed costae, and short, dense alar cells. Iwatsuki, 1987) has clarified the taxa in the genera closely related to Isopterygium, thus making this genus more clearly defined.
Isopterygium affusum
Leaves lax, close, subplanar, erect-spreading, smooth, usually wrinkled and distorted when dry, 1–3 mm long, 0.4–1.0 mm wide, ovate-lanceolate to ovate, symmetrical or often asymmetrical, acute to long -acuminate ; margins shallow, toothed above, entire below; costa none or weak, short and double; FIGURE 12. The small stems are only 1.3 cm long, 0.5–1.0 mm wide, the small leaves are ovate to ovate-lanceolate, symmetrical, sharp, rigid, close, concave, less than 1 mm long, with distinct alar regions. of short-rectangular to square or transversely elongated cells in 2–4 rows with 4–10 cells on margins, setae 0.6–1.0 cm long, capsules ovoid to ellipsoid, contracted below the mouth when dry, 0 .5–1.0 mm long.
Isopterygium jamaicense
Jujuy: Arroyo de los Matos ad Sierra Santa Barbara, Fries 43 (H, MO). of Sematophyllaceae is often confused with Isopterygium jamaicense. The gametophytes of the two are strikingly similar, except that Pterogonidium is a smaller plant with leaves that rarely spread as much as in I. Fortunately, Pterogonidium usually produces sporophytes and the erect capsules which look similar. jamaicense, has a single rather than a double peristome like all species of Isopterygium. no other locality information) Gilly & Hernandez 307 FIGURE 17.
Isopterygium subbrevisetum
The leaf morphology and phyllotaxy of this species may not seem very important until one thinks of the North American plants of Isopterygium tenerum. Among hundreds of North American Isopterygium plants studied by the senior author (Ireland, 1969), none approached the characteristic leaf morphology and phyllotaxy of I.
Isopterygium subglobosum
Stems up to 2.5 cm long, 1.0–1.5 mm wide, flat-leafed, simple or irregular and freely branched. The subglobose capsules, which do not contract under the mouth when dry, are very characteristic, but this may be only an environmental reaction to light, moisture, etc. represent, with no genetic basis.
Isopterygium tenerifolium
Stems up to 4 cm long, 2-3 mm wide, complanate, simple or irregular and freely branched. Discussion: Isopterygium tenerifolium is best known for its large plants with stems up to 4 cm long, 2-3 mm wide and leaves 1.0-1.5 mm long, ovate-lanceolate to oval, often curved and asymmetrical, pointed, lax, close. , complanate, usually wrinkled and distorted when dry, with poorly developed alarm cells, 1-2 short-rectangular to square cells on the margin, setae, 2-3 cm long, rarely up to 4 cm, and capsules ovate to ellipsoid, horizontal to drooping, contracted under the mouth when dry, 1.0–.
Isopterygium tenerum
Asexual reproductive bodies sometimes occur on stems, uniform, multicellular, simple or branched, often more than 0.5 mm long, green or brown, cells papillate. Stem and branch leaves similar but dorsal and ventral leaves distinct from lateral leaves, 0.75–1.0 mm long, subplanar, erect to spreading, often asymmetrical, broadly ligulate, dorsal and ventral leaves narrower than lateral leaves, broadly rounded to emarginate , lateral leaves very concave; margins sharply toothed above, the teeth bifid, toothed below, flat; costa short and double.
Platygyriella Cardot
In this respect it is like Ectropothecium, but in that genus there is only a single enlarged cell in the decurrencies, rather than several.
Platygyriella densa
Platygyriella pringlei
Stem ~5 cm long, irregular to regular, 1–2- branched with legs, in cross section without hyaloderm, central thread absent; branches 3–10 mm long, rarely longer, straight to curved; bracts axillary occasionally near branch tips. Vegetatively, the two can be separated from the brood branches in Platygyrium and from the homomallous leaves in Homomallium.
Pseudotaxiphyllum Z. Iwats
The epiphytic habitat and axillary bracts distinguish Platygyrium from Pylaisia as well as Homomallium. Axillary brood branches are less conspicuous and less common than in the more northern P .
Pseudotaxiphyllum distichaceum
Discussion: Pseudotaxiphyllum distichaceum is best recognized by its spaced, quadrate, flat, oval or oblong-lanceolate, often cultriform, asymmetrical, pointed leaves with toothed to toothed margins, narrow median leaf cells, poorly differentiated alar cells, sometimes 1–3 square to rectangular cells per margins and the usual presence of clusters of elongated, twisted vermiform propagules with 1–5 sharp teeth at the tips in the upper axils of the leaves. Pseudotaxiphyllum distichaceum has elongated propagules, twisted vermiform with 1–5 sharp teeth at the tips and located in leaf axils at or near the stem tips.
Pseudotaxiphyllum elegans
Pseudotaxiphyllum homomallifolium
The multicellular structures rarely found on the stems appear to be part of a developing branch primordium. They do not appear to be clearly separated from the rest of the primordium, sometimes not even visible on the stems at the base of mature branches as typical pseudoparaphyllia.
Pseudotaxiphyllum richardsii
Distribution and ecology: Rare; in Latin America known only from the state of Sonora in Mexico (Fig. 27);. Discussion: This species is recognized by the combination of small (0.5–1.0 mm long), ovate to ovate-lanceolate, acute to shortly acuminate leaves with toothed to toothed margins, which are strongly whorled when dry.
Puiggariopsis Menzel
These features are both typical of species of Symphyodon, but not of the capsules and smooth setae possessed by Taxiphyllum, Pseudotaxiphyllum, or Isopterygium, where T. Because the specific name of Taxiphyllum preceded that of Symphyodon, it required a new combination, S.
Pylaisia Schimp. in Bruch, Schimp
The description of the shape and ornamentation of the spores was taken from Nishimura (1989), who saw only 2–3 spores in a scanning electron microscope study of the peristome.
Pylaisia falcata
Mérida: Páramo de Los Granates, rond El Chimborazo, een sector van de Páramo do Los Granates, Griffin III & López F.
Pylaisia polyantha
Pylaisia selwynii
Stem and branch leaves slightly differentiated, ventral, dorsal and lateral stem leaves strongly differentiated, ventral 0.65-0.95 mm long, symmetrical, oblong-ovate, gradually long-acuminate, dorsal 1.0-1.3 mm long, slightly asymmetrical . , ovate, gradually acuminate, concave, lateral 0.85–1.2 mm long, strongly asymmetric, often cultriform, ovate-oblong, ± abruptly acuminate, concave; all stem leaves with margins far declinate, flat; costa short and double; median cells long hexagonal to linear, 8–20:1, smooth but with thickened cell end walls giving the impression of prorules, with firm walls, becoming thicker and somewhat porous towards insertion;. Branched leaves with differentiated dorsal and lateral leaflets, dorsal 0.8–1.1 mm long, half as long as laterals, symmetrical, spreading upright, lanceolate, gradually acuminate, laterals 1.1–1.3 mm long, slightly asymmetric. , broadly spreading, sometimes subfalcate, oblong-ovate, gradually or ± abruptly pointed, slightly concave; branch office.
Syringothecium Mitt
Syringothecium brasiliense
Perichae leaves 1.4–2.0 mm long, erect, triangular-lanceolate, gradually long-acuminate; margins mostly erect, subentire to serrate above. Setae 10-13 mm long, orange, straight, twisted; capsules 1–1.3 mm long, erect to suberect, cylindrical, not at all contracted below the mouth; annulus apparently not differentiated; operculum ~0.75 mm long, highly conical, obtusely oblique; exostome teeth ~600 μm high, orange, lanceolate, strongly demarcated, not shouldered, anteriorly at outermost base transversely striolate, directly above the papillose-striolate, often in irregular patterns, finely papillose-spiculose above, scarcely trabeculate posteriorly; endotome with a basal membrane of medium height, segments not perforated, extending to the height of the teeth but appearing higher in dry material, cilia usually single and short, sometimes rudimentary.
Syringothecium sprucei
Distribution and ecology: Known only from type specimens in southeastern Brazil; growing on bamboo shoots.
Taxiphyllum M. Fleisch
Iwatsuki (1963) clarified the taxonomy of Taxiphyllum, while Ireland (1969) revised the genus in Canada and the United States and later published a synopsis (Ireland, 1986) of North American taxa. Buck (1998) published a treatment of the genus for the West Indies and provided excellent illustrations for the four species occurring there.
Taxiphyllum deplanatum
Alar regions strongly differentiated with a large area of square to short-rectangular cells, 3-9 differentiated cells extending on margins. Alar regions undifferentiated or poorly differentiated with only a few square to short-rectangular cells, 1-5 differentiated.
Taxiphyllum laevifolium
Taxiphyllum ligulaefolium
However, such minute cleft serrations were not observed in any of the Mexican plants from the same collection (seen at FH but not at MICH) or in any of the plants from elsewhere that the authors studied. This species can be confused with a Pseudotaxiphyllum due to the few foliose pseudoparaphyllia present on the stems.
Taxiphyllum taxirameum
Crum, primarily because of the different type of branching pattern never seen to occur in other taxa of the genus Taxiphyllum. A revision of Plagiothecium and its related genera from Japan and her adjacent areas, I. Lectotypification of the Genus Isopterygium Mitt.
