Home Andean Bryophytes
Intro
Region
Name Search
Family List
Generic List
Andean Mosses XL database
Racomitrium Brid. Search in The Plant ListSearch in Index Nominum Genericorum (ING)Search in NYBG Virtual HerbariumSearch in JSTOR Plant ScienceSearch in SEINetSearch in African Plants Database at Geneva Botanical Garden Decrease font Increase font Restore font
 

Published In: Muscologia Recentiorum 4: 78. 1819[1818]. (Muscol. Recent.) Name publication detail
 

Project Name Data (Last Modified On 11/6/2012)
Acceptance : Accepted
Project Data     (Last Modified On 7/19/2014)
General Reference:
Tropicos Lookup Reference:

Notes     (Last Modified On 7/19/2014)
Notes:
Racomitrium contains about 40-50 species, often associated with aquatic habitats in cool temperate regions; about six species in the Neotropics. In the tropical Andes present in open mid to high montane and páramos; on rock, equally common in dry exposed sites or wet sites associated with streams. The distinctive sinuose cells of the leaf lamina are diagnostic (except at the basal margin), as are the often numerous short lateral branches can not confused with any other neotropical genus. Racomitrium has been subdivided into several genera including Bucklandiella, which is not followed in this treatment.
 
Racomitrium contiene ca. 40-50 especies, a menudo asociado con hábitats acuáticos en regiones templadas frías; ca. 7-8 especies en el Neotrópico. En Bolivia están presentes cuatro especies. Las células de la lámina foliar distintivamente sinuosas (excepto en el margen basal), así como las numerosas ramas laterales cortas son características de diagnóstico que impiden que se lo confunda con cualquier otro género neotropical. Racomitrium ha sido subdividido en varios géneros incluyendo Bucklandiella, que no es presentado en este tratamiento.


 

Export To PDF Export To Word

Plants medium sized to somewhat robust, in loose to dense mats or tufts, dark green to black or yellowish-brown to golden. Stems spreading to ascending, often with several to many short lateral branches; in cross-section outer 2-5 rows of cells small, thick-walled, inner cells larger, thick-walled, central strand absent. Leaves ovate-lanceolate to narrowly lanceolate, apex acute to acuminate and keeled or obtuse-rounded and cucullate; margins recurved on one or both sides, entire or irregularly erose-dentate; costae subpercurrent to long excurrent as a hyaline awn; lamina unistratose to 2-4 stratose along margin (and above), median cells long rectangular, walls finely sinuose; marginal base cells often differentiated in 1 to several rows as enlarge short to long rectangular cells with smooth walls; alar region little to distinctly differentiated. Dioicous. Perichaetia terminal on short lateral branches. Setae elongate, smooth, often twisted. Capsules erect, urn obloid-cylindrical; exothecial cells irregularly quadrate, rather thick-walled; stomata at urn base, superficial; annuli persistent; opercula rostrate; peristome teeth 16, divided to near base, often perforate at base, papillose. Calyptrae mitrate, smooth, base lacerated or slightly lobed. Spores spherical, lightly papillose.

 

Plantas medianas hasta algo robustas, en matas o manojos laxos hasta densos, verde oscuras hasta negras o pardo-amarillentas hasta doradas. Tallos patentes hasta ascendentes, a menudo con varias a muchas ramas cortas laterales; en corte transversal 2-5 filas externas de células pequeñas, con paredes gruesas, células internas mayores, con paredes celulares gruesas, cordón central ausente. Hojas ovado-lanceoladas hasta angostamente lanceoladas, ápices agudos hasta acuminados y carinados u obtuso-rotundos y cuculados; márgenes recurvados sobre uno o ambos lados, enteros o irregularmente erosionado-dentados; costa subpercurrente hasta largo-excurrente como una arista hialina; lámina uniestratificada hasta 2-4 estratos a lo largo del margen (y arriba), células mediales largo-rectangulares, paredes finamente sinuosas; células de la base del margen a menudo diferenciadas en 1 a varias filas de células alargadas corto- hasta largo-rectangulares con paredes lisas; región alar poco hasta conspicuamente diferenciada. Dioica. Periquecios terminales en ramas laterales cortas. Setas alargadas, lisas, a menudo torcidas. Cápsulas erectas, urna obloide-cilíndrica; células exoteciales irregularmente cuadradas, paredes celulares bastante gruesas; estomas en la base de la urna, superficiales; anillo persistente; opérculo rostrado; peristoma con 16 dientes, partidos hasta cerca de la base, a menudo perforados en la base, papilosos. Caliptra mitrada, lisa, base lacerada o escasamente lobada. Esporas esféricas, finamente papilosas.

 

Export To PDF Export To Word
1. Leaves ovate, oval or broadly elliptical, apices broadly rounded; upper laminal cells irregularly isodiametric, irregular in shape, not appearing sinuose … R. molle
1. Leaves ovate-lanceolate to lanceolate, apices acute to acuminate; upper laminal cells distinctly sinuose … 2.
2. Leaf apices muticous or hyaline; apex acuminate … 3.
2. Leaf apices concolorous; apex acute to obtuse-rounded … 5.
3. Leaf margins papillose-serrate, hyaline; laminal cells distinctly papillose … R. geronticum
3. Leaf margins entire; laminal cells smooth … 4.
4. Marginal cells undifferentiated or 2-3(-5) hyaline or yellow mostly sinuose cell walls; leaves muticous or very short hair point … R. subsecundum
4. Marginal cells at leaf base differentiated, 10-15 hyaline cells with smooth, non-sinuose cell walls; leaves with a hyaline awn … R. crispipilum
5. Leaf apices acute, margins 2 or more stratose … R. lamprocarpum
5. Leaf apices obtuse-rounded, margins unistratose … 6.
6. Stem and branch tips secund; leaves falcate-secund … R. dichelymoides
6. Stem and branch tips not distinctly secund; leaves not falcate-secund … R. cucullatifolium = R. crispipilum
 
 
 
© 2014 Missouri Botanical Garden - 4344 Shaw Boulevard - Saint Louis, Missouri 63110