Echinodorus tenellus
Encyclopedia
Synonyms
Alisma tenellus Martius; Alisma tenellum; Echinodorus naine; Echinodorus parvulus Engelm.; Echinodorus tenellus var. ecostatus; Echinodorus tenellus (Mart.) Buch. var. latifolius (Seub.) FassettFassett
Fassett as a surname may refer to:* Norman C. Fassett expert on aquatic plants, professor of botany and curator of the Herbarium at the University of Wisconsin–Madison* Cornelia Adele Strong Fassett , an American painter...
; Echinodorus tenellus (Mart.) Buch. var. parvulus (Engelm.) Fassett; Helianthium parvulum (Engelm.) Britt.; Helianthium tenellum Britt.; Sagittaria microfolia.
Distribution
Echinodorus tenellus is found throughout North, Central, and South AmericaSouth America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
, especially in Southern Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
and the southern states
Southern United States
The Southern United States—commonly referred to as the American South, Dixie, or simply the South—constitutes a large distinctive area in the southeastern and south-central United States...
of North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
. It may be the widest-distributed of all the Echinodorus
Echinodorus
Echinodorus is a genus of plants in the family Alismataceae and distributed in the Western Hemisphere. Its scientific name is derived from Ancient Greek echius – rough husk, and doros – leathern bottle, alluding to ovaries, which in some species are armed with persistent styles,...
, with the most northerly range.
There may be several different variations, which have at times been given separate taxonomic
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
rank.
It is only rarely found in running water. Normally it is found in wet sand on the shores of pools or in inundated zones of rivers.
Description
The leavesLeaves
-History:Vocalist Arnar Gudjonsson was formerly the guitarist with Mower, and he was joined by Hallur Hallsson , Arnar Ólafsson , Bjarni Grímsson , and Andri Ásgrímsson . Late in 2001 they played with Emiliana Torrini and drew early praise from the New York Times...
of E. tenellus are narrowly elliptical or lanceolate. At different times during the plant's life cycle
Biological life cycle
A life cycle is a period involving all different generations of a species succeeding each other through means of reproduction, whether through asexual reproduction or sexual reproduction...
, the blade of the leaf is scarcely distinguishable from the petiole
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...
, while at other times the petiole is 10 to 15 times as long as the blade, which may be 1-4 cm long and 0.2-1 cm wide, with a pointed tip. The base is decurrent to the petiole and has between one and three veins.
The stem is thin, erect, often curved and radicans, and may be 3-20 cm long. In small plants, the stem ends in a single inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
(umbel or coil); in larger plants the inflorescence is racemose, composed of two whorls placed one above the other. Bracts are free and 2-6 mm long in the first whorl. Pedicels are 1-3.5 cm long. Sepals are 3 mm long, membraneous, and usually have five fine ribs. During ripening, the sepals enlarge and reach a length of up to 6 mm and fully cover the aggregate fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
. A specimen may have six to nine stamens, each about 1 mm long. Anthers are 0.25 mm wide by 2.25 mm long, which is three times shorter than the filaments. It may have sixteen to eighteen pistils. The achenes are compressed, and arched in the apical part; they are (0.9) - 1.1 - (1.3) mm long, and black, with three lateral ribs. The basis of the stylar beak is under the level of the tip of the nutlet
Pyrena
Pyrena or pyrene is the name for a nutlet resembling a seed, or the kernel of a drupe or drupelet....
and may be 0.1-0.3 mm long.
It is a highly variable species according to its geography and environmental conditions.
Cultivation
Easy to grow in tropical aquariums or outside in and around ponds in warmer regions. It will form a mat in good conditions and in plenty of light. Likes a good substrateSubstrate (aquarium)
The substrate of an aquarium refers to the material used on the tank bottom. It can affect water chemistry, filtration, and the well-being of the aquarium's inhabitants, and is also an important part of the aquarium's aesthetic appeal...
of small grained gravel / sand. Benefits from additional CO2. Ideal for the fore - mid-ground of the aquarium
Aquarium
An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...
. Will tolerate lower temperatures than many other Echinodorus
Echinodorus
Echinodorus is a genus of plants in the family Alismataceae and distributed in the Western Hemisphere. Its scientific name is derived from Ancient Greek echius – rough husk, and doros – leathern bottle, alluding to ovaries, which in some species are armed with persistent styles,...
, down to at least 68F (20C) or lower. Propagates readily by runners.