Fontinalis and Vesicularia

Scientific name

Fontinalis Hedw. and Vesicularia (C. Müll.) C. Müll.

Common names

Java moss, willow moss, christmas moss

Family

Fontinalaceae (Fontinalis), Hypnaceae (Vesicularia)

Similar genera

Fissidens, Taxiphyllum, and other species of terrestrialterrestrial:
(adj) growing on land as opposed to living in water
mosses

Native distribution

cosmopolitancosmopolitan:
(adj) essentially worldwide in distribution

Species cultivated

Fontinalis antipyretica Hedw.

Vesicularia dubyana (Müll) Broth.

V. ferriei (Cardot & Thér.) Broth.

V. montagnei (Schimp.) Broth.

V. reticulata (Dozy & Molk.) Broth.

Adventive distribution

information not available

Weed status

not weedy

Habit

creeping, amphibiousamphibious:
(adj) of a plant able to live on land or in water
, epiphyticepiphytic:
(adj) of a plant growing on another plant but not parasitic; plant grown on may be alive or, e.g., a dead tree trunk
, growing on wood and rocks

Brief description

Perennial perennial:
(adj) (of a plant) having a life cycle of more than two years
mosses. Non spore-producing generation (gametophyte) is dominant, forming a mat of light to dark green stems. Stems leafy, relaxed or flattened, soft, simple or much-branched, naked or bearing elongate rhizoids along ventralventral:
(adj) of the front of an organ or the side facing or nearest the axis (syn. adaxial) (compare dorsal); upper surface
surface (roots absent); branching pattern variable, pinnatepinnate:
(adj) in the form of a feather; of, e.g., leaflets, lobes, or veins: arranged in two rows along an axis
to dichotomous to apparently random. Leaves alternatealternate:
(adj) (of leaves) bearing one leaf per node; placed singly on the stem at different heights
(3-ranked in Fontinalis), lanceolatelanceolate:
(adj) lance-shaped; widest point below the middle, tapering to the apex
to ovateovate:
(adj) egg-shaped in outline; generally with the broad end at or near the base
. Spore-producing generation (sporophyte) emersedemersed:
see emergent
. Dispersal by spores and stem fragments.

Natural habitat

shallow water, splash zone, and boggy ground

Additional comments

Fontinalis and Vesicularia are genera in Bryophyta (mosses). Fontinalis is less common in the aquarium trade, while Vesicularia, which adapts easily to underwater culture, is frequently utilized. Vesicularia has smaller leaves than Fontinalis. It is sold in various different forms, e.g., willow moss, christmas moss, and Java moss. All clearly have different growth forms, varying in the degree and pattern of stem branching. It is unknown which species or varieties these represent. Critical taxonomic appraisal is required before they can be accurately identified. At present, they are all considered varieties of V. dubyana. There is also some debate as to the actual species identity of the Vesicularia that is widely distributed. Some sources suggest that the species is actually V. reticulata (Dozy & Molk.) Broth., and not V. dubyana. Vesicularia reticulata also originates from Southeast Asia.

Fontinalis has high morphological variability throughout the genus as well as within single collections of one species. Fontinalis is generally larger, with swollen stem and branch tips, but this is often dependent on growing conditions. The leaves of Fontinalis are keeledkeeled:
(adj) having a keel; sharply creased
with a decurrentdecurrent:
(adj) extending downward, beyond the point of insertion
base and typically lack a costacosta:
(n) midvein of leaf or pinna or rachis of pinnately compound leaf
. If growing in swift waters the keelkeel:
(n) a sharp crease or ridge
can easily tear, appearing as two separate leaves.

Vesicularia is poorly studied, and synonymy within the genus and with other genera is to be expected until further taxonomic studies are done. The leaves of Vesicularia are often dimorphic with smaller ventralventral:
(adj) of the front of an organ or the side facing or nearest the axis (syn. adaxial) (compare dorsal); upper surface
leaves, they lack a keelkeel:
(n) a sharp crease or ridge
, and they have a short and double costacosta:
(n) midvein of leaf or pinna or rachis of pinnately compound leaf
. Vesicularia and Taxiphyllum are similar in both gametophytic and sporophytic characteristics, making the two very difficult to distinguish. Vesicularia is often more pinnately branched, while Taxiphylllum is irregularirregular:
(adj) asymmetrical
, but again this feature is variable depending on growing conditions.