Dacryophyllum falcifolium, a new North American genus and species (Musci: Hypnaceae) from California

2004·3.4 MB·

by  R R Ireland

DaeryophyHum falcifolium, a New Norlli American Genus and
Species (Musci: Hypnaceae) from California
Robert R. Ireland
Botany, National Museum of Natural History. P.0. Box 37012, Smithsonian Institution,
Washington, I).C. 20013-7012, U.S.A. [email protected]
Abstract. Dacryophyllum falcifolium, a new nition. The publication of this new genus is es¬
North American genus and species of moss, is de¬ sential for the forthcoming Bryophyte Volume 28
scribed and illustrated. The taxon is described from of the Flora of North America.
sterile California collections, where it occurs on
calcareous rock in redwood forests in Monterey and Daeryophylluin falcifolium Ireland, gen. et sp.
Santa Cruz Counties. The new moss genus Dacry¬ nov. TYPE: U.S.A. California: Santa Cruz Co.,
ophyllum is considered a member of the large pleu- cliff on opposite side of South Fork Fall Creek
rocarpous family Hypnaceae and is morphologically from Blue Cliff, above Lime Kilns. Fall Creek
close to Taxiphyllum. Division, Henry Cowell Redwoods State Park,
near Felton, ca. 37°03'30"N, 122°05'45"W,
Key words: California, Dacryophyllum, Hypna¬
244 m, on vertical (ace of calcareous rock in
ceae, Musci, North America, Taxiphyllum.
woods, 12 June 1999, k. M. Kellman 704 (ho-
Four collections of an unknown moss growing lotype, CAS; isotypes, DUKE, MO, NY, UC,
US). Figure I.
on calcareous substrates from three different lo¬
calities in the redwood forests of Monterey and
In ramis complanate foliatis in pseudoparaphylliis an-
Santa Cruz Counties, California, located in the gustc foliosis in nervis caulis centralis nnllis et in foliis
central coastal part of the state, recently were falcatis laevibus ecostatis in cellulis numerosis basilaribus
made by Kenneth M. Kellman and sent to me for juxta caulem retroprorulis et margine infeme saepe binate
denticulatis distinetum.
identification. An examination of the four collec¬
tions revealed that the plants have several dis¬ Plants in thin mats, complanate-foliate, light- to
tinctive features that show a relationship to the yellow-green, glossy; stems to 1.5 cm, 0.8—1.0 mm
genus Taxiphyllum Fleischer, a member of the wide, prostrate, simple or sparingly and irregularly
family Hypnaceae. Similarities in the plants’ col¬ branched, cortical cells moderately small, thick-
or, growth habit, branching pattern, leaf arrange¬ w; died. in 2 or 3 rows, central cells large, thin-
ment, costa features, leaf shape, leaf margins, walled, central strand lacking; rhizoids fewr. smooth,
leaf cell prorations, and presence of foliose stem ventrally inserted, single or in clusters below leaf
pseudoparaphyllia all indicate a close relation¬ insertion; axillary hairs ca. 108 gin long, mainly in
ship with some members ol the fly, maeeae, es¬ axils of uppermost leaves near apical bud, consist¬
pecially Taxiphyllum. However, several of its ing of 1 short brown basal cell and 1 or 2 elongate
morphological characters are sufficiently differ¬ hyaline distal cells; pseudoparaphyllia narrowly fo¬
ent to justify describing a new genus and species. liose, 2 to 4 cells wide, serrulate to toothed, some¬
I he species is easily recognized by its small size times with single-celled, large teeth, usually mixed
(plants to 1.5 cm), its complanate-foliate, pros¬ with some entire filamentous pseudoparaphyllia, 3
trate stems, its broadly falcate leaf apices, its to 6 cells long, branch primordium not evident
usual lack of a costa or a short, indistinct double among pseudoparaphyllia. Stem and branch leaves
one, its short, broad apical leaf cells (shorter and similar, stiff, appressed-imbricate, flat, smooth,
broader than in most North American Taxiphyl¬ asymmetric, 0.3—0.5 X 0.1—0.2 mm, oblong-lan¬
lum species), its basal row of leaf cells at the ceolate, acute to obtuse, falcate, margins plane, ser¬
stem insertion with large prorulae at their prox¬ rulate, becoming serrate at leaf base, serrations of¬
imal ends, and its foliose, serrulate to toothed ten formed by two basal cells abutting, broadly
pseudoparaphyllia, sometimes with single-celled, incurved on one side at base, nondecurrent; costa
large teeth, usually mixed with entire filamentous lacking or indistinctly double; cells thin to mod¬
pseudoparaphyllia. The calcareous substrate erately thick-walled, linear-flexuose to rhomboidal,
upon which it grows is also a clue to its recog¬ especially near leaf apex, smooth or often with mi-
Novon 14: 70-74. 2004.
Volume 14, Number 1 Ireland 71
2004 Dacryophyllum falcifolium from California
cells at stem insertion. —G. Pseutloparaphyllia (note large tooth on uppermost pseudoparaphyllium). Drawn by I’. M.
Eckel from isotype (US).
mile prorulae on abaxial surface at distal and prox¬ prorula at proximal end on the abaxial surface; alar
imal ends, prorulae sometimes more prominent on cells 8—19 X 6—7 yam, quadrate to rectangular, in
basal cells, with walls nonpitted; median cells 32— 1 to 4 rows with 2 to 7 cells in marginal row. Asex¬
45 X 4—5 yam; apical cells 10-28 X 5—7 yam; basal ual reproductive bodies lacking. Plants sterile, sex
row of cells at stem insertion each with a large organs unknown.
72 No von
Etymology. The genus name is derived from paratype (Kellman & Shevock 2671) were sent to
die Greek dakryo, meaning to shed tears or weep, A. J. Shaw (DUKE) who conducted a DNA test on
and phyllon, meaning leaf, referring to the basal a single chloroplast gene from plants of the two
leaf cells at stem insertion with proximal prorulae specimens in order to see how the unknown Cali¬
on the abaxial surface (Fig. IF) giving the appear¬ fornia moss was related to many other pleurocar-
ance of tears, and the downward-pointing leaf api¬ pous moss species he had tested in the past. The
ces adding to the weeping meaning (Fig. 1A). The sequencing was done on the trnL-trnF region (Ta-
species epithet is from the Latin /aids, meaning berlet et al„ 1991). Me admitted (pers. comm.) that
sickle, and folium, meaning leaf, referring to the “a single chloroplast gene doesn’t give much useful
sickle-shaped leaf apices of the plant (Fig. Ill, low¬ resolution, especially in the Hypnales, where spe¬
est leaf outline). cies, genera, and even some families are extremely
Distribution and habitat. Endemic to Califor¬ closely related in a genetic sense.” The two spec¬
nia. The collections were made in Coast Redwood imens he tested yielded identical sequences. The
forests on vertical surfaces of shaded, calcareous closest species that it came to in his DNA test was
rock cliffs and rock outcrops at elevations of 50- Hypnum pallescens (Hedwig) P. Reauvois, which as
244 m. According to the type collector the localities he stated “gives some support to the Hypnaceae
have a typical Mediterranean climate, with a dry, idea” where I thought the species belonged. How¬
warm summer and a cool, rainy winter, which is ever. it is not very close morphologically to Hypnum
generally from October to April. The common trees pallescens or to any other species of Hypnum. Hyp¬
at the sites are Sequoia sempervirens (I). Don) En- num taxa often have stems that are regularly pin¬
dlieher, Acer macrophyllum Pursh, and Lithocarpus nate. leaves that are often falcate-secund, standing
densifiorus (Hooker & Arnott) Rehder. The mosses out from the stems, with acuminate to long-subulate
associated with Dacryophyllum are Brachythecium apices, apical cells that are elongate, and the pseu¬
species, Didymodon species, Eissidens crispus Mon- doparaphyllia on the stems are usually broadly fo¬
tagne, and Isothecium myosuroides Bridel. liose, with or without teeth or with ciliate margins.
Morphology and relationship. Dacryophyllum I originally intended to describe this unknown
Jalcifolium is primarily distinct because of its pros¬ moss as a Taxiphyllum, a member of the Hypnaceae
trate small-sized plants, stems to only 1.5 cm long that I have worked on for several years. However,
and 0.8—1.0 mm wide (Fig. I A), its small, com- 1 had some reservations and wanted to confirm its
planate-foliate leaves, 0.3—0.5 mm long, with acute generic position, so I sent some of the holotype and
to obtuse leaf apices, usually strongly falcate (Fig. one of the paratype (Kellman & Shevock 2671)
Ill), and its serrulate to serrate leaf margins (Fig. specimens to William R. Ruck (NY), an authority
11)—F). The basal cells on the margins in the alar on the pleurocarpous mosses. He thought (pers.
region often have two abutting cells forming a ser¬ comm.) the genus was close to the family Necker-
ration similar to the basal serrations in the pleu- aceae, which has many genera with a somewhat
roearpous moss Conardia compacta (J. K. A. Mull¬ similar appearance and morphology. Isodrepanium
er) II. Robinson (Crum & Anderson, 1081) and lentulum (Wilson) Britton, e.g., has a superficial
those on the leaf margins of several species of the similarity with its smooth, falcate, cultriform leaves,
acrocarpous moss Philonotis (Fig. IE, just above but it differs in many important microscopic mor¬
letter). The apical leaf cells are noticeably short phological features, especially the lack of large pro¬
and broad, 10—28 X 5—7 gm (Fig. ID). The leaf rulae on the abaxial surface at the proximal ends
cells have minute prorulae on the abaxial surface of the basal cells at the stem insertion. Other taxa
on the distal ends of the cells or sometimes at both in the Neckeraceae have rhombic to rhomboidal
ends (Fig. IE). The costa is usually lacking or in¬ leaf cells, usually without prorulae, and sometimes
distinct and short and double. The basal row of leaf paraphyllia are present or the pseudoparaphyllia
cells at stem insertion is unique because of the that are present in some species are narrowly foli¬
large prorulae at the proximal ends on the abaxial ose with entire margins. He excluded the plants
surface (Fig. IF). One other unique feature is the from Taxiphyllum because (1) the plants, especially
narrowly foliose, 2 to 4 cells wide, serrulate to those from North America, were too small (Taxi¬
toothed pseudoparaphyllia, sometimes with a sin¬ phyllum in Asia, however, can be very small, e.g.,
gle-celled, large tooth (Fig. 1C, uppermost pseu- Taxiphyllum arcuatum (Bosch & Sande Lacoste) Si
doparaphyllium), usually intermixed with filamen¬ He); (2) the pseudoparaphyllia had large teeth,
tous entire pseudoparaphyllia, 4 to 6 cells long composed of almost whole cells (rather than ser¬
(Fig. Hi. middle pseudoparaphyllium). rulate with only cell ends projecting): and (3) the
Plants of the holotype (Kellman 704) and one most important reason was the cells at the leaf in-
Volume 14, Number 1 Ireland 73
2004 Dacryophyllum falcifolium from California
sertion with the stem were strongly prorulose at mentous pseudoparaphyllia. Often, in Isopterygium
their proximal ends on the abaxial surface and pro¬ species, however, there is some evidence that a
ject clown from the leaf base. He stated that he had branch primordium may sometime develop because
not seen leal insertion cells of that type before. Il of a difference in coloration, often an orange area,
was the presence of prorulose cells at the leal in¬ among the pseudoparaphyllia, or else some differ¬
sertion that prompted me to seek the opinion of two entiated stem cells may lx* evidence that a branch
other bryologists, namely Lewis E. Anderson primordium is present at that particular site. This
(DUKE) and Harold E. Robinson (US). Both (pels, type of evidence of a branch primordium was dif¬
comm.) thought the plants should he described as ficult to observe on the stems among the pseudo¬
a new genus because of major differences with Tax¬ paraphyllia of Dacryophyllum because the clus¬
iphyllum, especially because of the unique proru¬ tered pseudoparaphyllia often obscured the view of
lose cells at the leaf insertion first observed by the stem cells, which made it difficult to note any
Buck, who also was in favor of recognizing it as a evidence of differentiated cells among them. An¬
new genus. other explanation could be that they are not yet
fhe plants of Dacryophyllum falcifolium are fully developed in the specimens examined, per¬
somewhat close in appearance to some species in haps due to the absence ol the necessary environ¬
the genus Taxiphyllum; both genera grow on cal¬ mental factors at the time when the plants were
careous substrates and share some common mor¬ collected. Sometimes some of the pseudoparaphyl¬
phological charac teristics. The similarities are the lia looked like paraphyllia when only one was seen
green or yellow-green, glossy, prostrate, mostly at a particular site on the stem. I lowever, none were
complanate-foliate, simple or sparingly branched observed on the abaxial or adaxial surfaces of the
plants, the leaves that are nondecurrent often with stems like paraphyllia in species that possess them,
serrulate to serrate margins, sometimes with obtuse e.g., Cratoneuron and Thuidium species, where
apices, the costa that is almost lacking in Dacry¬ they occur randomly all around the stems. I there¬
ophyllum and sometimes so in Taxiphyllum, the fore believe all of them are pseudoparaphyllia.
abaxially prorate leaf cells with the prorulae very Dacryophyllum probably occurs elsewhere in
prominent at the distal cell ends in Taxiphyllum, California, and il should be searched for in calcar¬
present but usually minute in Dacryophyllum, and eous habitats throughout the state. If sporophytes
the presence ol foliose pseudoparaphyllia. Dacry¬ can be found they would undoubtedly reveal ad¬
ophyllum is distinguished by the falcate leaf apices, ditional important information about the new genus
the lack of a central strand of cells in the stem, and species. Also, it will be very interesting to see
and the pseudoparaphyllia that arc* much narrower if the plants always occur in the Redwood forests
than in Taxiphyllum (Ireland, 1971. fig. 57). Some¬ of California.
times the pseudoparaphyllia have single-celled,
Paratypes. U.S.A. California: Monterey Co., near S
large teeth, and they are mixed with filamentous
fork of Little Sur River below Old Coast Road, El Sur
pseudoparaphyllia, neither of which Taxiphyllum Ranch, 28 June 2003, K. 17. Kellman 3037 (CAS. DUKE,
possesses. In addition, the leaf cells often have pro¬ MO, NY, UC, LIS); Santa Cruz Co., Coast Redwood forest
rulae on the abaxial surface at both ends, and, most where Cave Gulch crosses under Empire (trade, on cam¬
pus of U. of California, 8 Eeb. 2003, A. 17. Kellman & J.
importantly, the basal row of cells at the leaf in¬
Shevock 2671 (CAS, DUKE, US); cliff on opposite side of
sertion is strongly prorulose at the proximal ends. South Fork Fall Creek from Rlue Cliff, above Lime Kilns,
The branch primordia are not evident among the Fall Creek Division, Henry Cowell Redwoods State Park,
pseudoparaphyllia in Dacryophyllum as they are in near Felton, 15 June 2003, K. M. Kellman 2005 (topo-
types, CAS, DUKE, MO, NY, UC, US).
most species ol Taxiphyllum where the raised
branch primordia on the stem are surrounded by Acknowledgments. I am especially grateful to
the pseudoparaphyllia. At first the pseudopara¬ Kenneth M. Kellman of Ben Lomond, California,
phyllia appeared to be paraphyllia but they always who first collected and sent me the new moss for
or nearly always occur in clusters in the leaf axils identification, also providing me with important
like pseudoparaphyllia, and they are not scattered ecological data and a list of associated plants. I
along the stems like paraphyllia. They are, how¬ thank H. E. Robinson, Smithsonian Institution, for
ever. present on the stems around the young de¬ his support, comments on the morphology and re¬
veloping branches and on the bases of more mature lationship of the new taxon, as well as for his sug¬
branches like typical pseudoparaphyllia. The lack gestion of the genus name and the preparation of
of obvious, raised branch primordia sometimes oc¬ the Latin description. I appreciate the interest and
curs on the stems in other genera that have pseu¬ observations by W. R. Buck, New York Botanical
doparaphyllia, e.g.. Isopterygium, which has fila¬ Garden, on the morphology of several features of
74 Novon
the new species, especially his photographs of the benefited from the discussion of the morphology of
prorulae on the basal cells that assisted the artist. the new taxon by the former, f inally, the invaluable
I am indebted to A. J. Shaw, Duke University, for assistance of Scott Whittaker, who took pictures of
conducting the DNA test on the plants and for his the leaves of the plants with the SEM to better ob¬
comments. I am grateful to I.. E. Anderson, Duke serve the location of the prorulae, is greatly appre¬
University, for rendering his opinion on the mor¬ ciated.
phology and taxonomic status of the new species.
Literature Cited
1). H. Norris, University of California, brought my
Crum, H. & I,. E. Anderson. 1981. Mosses of Eastern
attention to important morphological information,
North America, Vol. 2. Columbia Univ. Press, New
which I gratefully acknowledge. I’. M. Eckel, Mis¬
York.
souri Botanical Garden, did the illustrations, and I Ireland, R. R. 1971. Moss pseudoparaphyllia. Bryologist
owe her a debt of gratitude for the time taken to 74: 312-330.
Taberlet, P. E. Gielly, G. Pautou & J. Bouvet. 1991. Uni¬
produce her excellent drawings. 1 thank S. He and
versal primers lor amplification of three non-coding re¬
V. C. Hollowed, Missouri Botanical Garden, for
gions of chloroplast DNA. PI. Molec. Biol. 17: 1105—
their helpful review of the paper, and I also have 1 109.