Scorpidium scorpioides
Calliergonaceae
hook scorpion-moss, scorpidium moss
leaves almost orbicular to broadly ovate-lanceolate, abruptly or gradually narrowed to apex, suddenly curved distally or rarely straight, strongly concave, (0.7–)1–2.4 mm wide;
apex obtuse, usually apiculate, acute, or acuminate;
costa double or occasionally single, rarely ecostate, when single often 2-fid, reaching below to rarely slightly beyond mid leaf;
alar cells 5–20;
medial laminal cells (shorter 1/2 of leaf) 32–200(–210) µm, cell ends square, rounded, or short fusiform-narrowed.
leaves straight or falcate, or from straight base suddenly curved, plicate or not;
costa single, usually long, or double and usually short;
alar cells differentiated or not, often inflated;
medial laminal cells linear or short-linear, 1-stratose, smooth.
long, smooth.
dioicous.
with exostome external surface almost entirely cross striolate to almost entirely dotted proximally.
± horizontal (occasionally inclined in Loeskypnum), cylindric, curved;
stomata long-pored;
annulus separating or not;
operculum conic;
peristome perfect;
exostome yellow-brown or brownish, external surface ± reticulate proximally, rarely entirely cross striolate, papillose distally, border ± widened at transitional zone in outer peristomial layer pattern, margins dentate or slightly so;
endostome basal membrane high, segments long, not or narrowly perforate, cilia nodose.
cucullate, smooth.
with inner leaves erect, straight, lanceolate, ovate, oblong, or slightly obovate, plicate or not, costa single, usually well developed;
vaginulae with paraphyses or naked.
Scorpidium scorpioides
Calliergonaceae
Scorpidium scorpioides is usually recognized by its large size and strongly concave, broad and usually shortly pointed leaves with a short single or double costa. Straight-leaved phenotypes, which are rare, look very different from the falcate-leaved ones, but, except for leaf curvature, there does not seem to be any difference between these phenotypes. Specimens with straight leaves could be confused with Pseudocalliergon turgescens, and the differences between the two are given under the latter. Although S. scorpioides superficially looks very different from the other two members of the genus, these differences are mainly found in characters, such as size and leaf shape, that affect the appearance of the plant to the naked eye. Molecular evidence and critical microscopic features of, for example, stems, alar cells, and exostomes relate this species to S. cossonii and S. revolvens. Based on molecular evidence, S. scorpioides is an ingroup within S. cossonii, and is thus an example of a species with a number of autapomorphies that are easily visible to the naked eye, in a genus where the two other members have a more generalized appearance.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Genera 7, species ca. 22 (7 genera, 20 species in the flora).
Genera of Calliergonaceae are fairly well circumscribed based on morphology and molecular data, and are well differentiated from Amblystegiaceae. All species, except sometimes Scorpidium revolvens and S. scorpioides, have a reticulate proximal external surface of the exostome, whereas all members here treated in Amblystegiaceae, except Conardia and Tomentypnum, are cross striolate on the outer basal exostome. Many Calliergonaceae species become translucent red when growing in habitats exposed to sunlight; this is never the case among Amblystegiaceae.
Morphological features further characterize the genera Calliergon, Loeskypnum, Sarmentypnum, Straminergon, and Warnstorfia. When shoots grow erect, these are radially rather than distichously branched, except in species that are sparsely branched. Rhizoid initials, and sometimes rhizoids, are frequently found in various parts of the leaf lamina, especially close to the apex. Leaf-borne rhizoid initial cells are easily recognized in being slightly wider than the surrounding laminal cells and lacking the pigments of the latter. Among Amblystegiaceae genera, rhizoid initials and rhizoids are found in leaves only in Conardia, in which they often occur both close to apices and on the abaxial costa, and in Tomentypnum, in which they are found only on the abaxial surface of the costa.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Stems with hyalodermis present or partial | → 2 |
1. Stems with hyalodermis absent | → 3 |
2. Alar cells few, strongly inflated, regions small, from margins at most 50% distance to costa; rhizoid initials on stem, at or just before leaf insertions. | Scorpidium |
2. Alar cells many, inflated or strongly inflated, regions large, from margins ± to costa; rhizoid initials frequently present in leaves, especially near apex. | Sarmentypnum |
3. Stem central strands absent; stem leaves usually plicate; alar cells not differentiated. | Hamatocaulis |
3. Stem central strands present; stem leaves not or indistinctly plicate; alar cells differentiated | → 4 |
4. Stem leaf alar cells slightly inflated, walls incrassate, regions indistinctly delimited; axillary hairs well developed, many, distal cells yellow-brown or brownish when young; plants often yellow-brown or copper brown, never red. | Loeskypnum |
4. Stem leaf alar cells inflated or strongly so, walls thin or sometimes incrassate, regions distinctly or indistinctly delimited; axillary hairs well developed and many, or not well developed and few, distal cells hyaline (brownish in Sarmentypnum trichophyllum); plants variously colored, sometimes red | → 5 |
5. Stem leaves straight or falcate, triangular to ovate or narrowly ovate, gradually narrowed to apex; apices acuminate or obtuse | → 6 |
5. Stem leaves ± straight, ovate, broadly ovate, or rounded-triangular, ± abruptly narrowed to apex; apices rounded, rounded-obtuse, or rounded-apiculate | → 7 |
6. Sexual condition autoicous; translucent red pigment extremely rare, when present usually overlain by brown pigment, appearing reddish brown; outer pseudoparaphyllia narrow; alar regions narrowly transversely triangular, from margins possibly to costa, or regions almost quadrate, with supra-alar cells often in ovate group along basal margin, region somewhat indistinctly delimited. | Warnstorfia |
6. Sexual condition dioicous; translucent red pigment often present; outer pseudoparaphyllia broad; alar regions transversely triangular, from margins ± to costa, distinctly delimited. | Sarmentypnum |
7. Stem leaves broadly ovate to broadly rounded-triangular; apices rounded or obtuse; axillary hair distal cells 2-8(-10), hairs well developed, many. | Calliergon |
7. Stem leaves ovate, narrowly ovate, or triangular; apices short rounded-apiculate or rounded; axillary hair distal cells 1-2(-7), hairs not well developed, usually few | → 8 |
8. Stem leaf apices rounded; alar regions ovate or broadly ovate; stems sparsely branched; plants pale or whitish green to yellow-green. | Straminergon |
8. Stem leaf apices usually rounded-apiculate, rarely rounded; alar regions transversely triangular; stems sparsely to densely branched; plants deep green to clear red. | Sarmentypnum |
BC
MI Flora
MN Wildflowers
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
