grass
Poaceae ( ), also called Gramineae ( ), is a large and nearly ubiquitous family (biology), family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos, the grasses of natural grassland and spe ...
genus in the tribe
Paniceae
Paniceae is a large tribe (biology), tribe of the subfamily Panicoideae in the grasses (Poaceae), the only in the monotypic taxon, monotypic supertribe Panicodae. It includes roughly 1,500 species in 84 genera, primarily found in tropical and sub ...
Madagascar
Madagascar, officially the Republic of Madagascar, is an island country that includes the island of Madagascar and numerous smaller peripheral islands. Lying off the southeastern coast of Africa, it is the world's List of islands by area, f ...
. It was described by French botanist
Aimée Antoinette Camus
Aimée Antoinette Camus (1 May 1879 – 17 April 1965) was a French botanist. She was best known for her study of orchids and oaks. Camus also has the legacy of authoring the second highest number of land plant species among female scientist ...
in 1948, who named it in honour of
Mary Agnes Chase
Mary Agnes Chase (April 29 1869 – September 24 1963) was an American botanist who specialized in agrostology, the study of grasses. Although lacking formal education past elementary school, Chase was able to rise through the ranks as a botanis ...
. Its two species were also classified in the genera '' Echinolaena'' and ''
Panicum
''Panicum'' (panicgrass) is a large genus of about 250 species of Poaceae, grasses native throughout the tropical regions of the world, with a few species extending into the northern temperate zone. They are often large, Annual plant, annual or P ...
'', but
phylogenetic
In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...
analysis confirmed that they form a distinct lineage.
Species of the genus are erect grasses, tall. They have ovate to linear leaves. The inflorescence is a terminal, one-sided
raceme
A raceme () or racemoid is an unbranched, indeterminate growth, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are ...
, sometimes in clusters of up to five. The
glumes
In botany, a glume is a bract (leaf-like structure) below a spikelet in the inflorescence (flower cluster) of grasses (Poaceae) or the flowers of sedges (Cyperaceae). There are two other types of bracts in the spikelets of grasses: the lemma an ...
have prominent stiff hairs. The
spikelet
A spikelet, in botany, describes the typical arrangement of the inflorescences of grasses, sedges and some other monocots.
Each spikelet has one or more florets. The spikelets are further grouped into panicles or spikes. The part of the sp ...
s are paired and have no awns. The genus can be distinguished from similar forest grass species in ''
Acroceras
''Acroceras'' is a genus of tropical and subtropical plants in the grass family.
The genus is widespread across warmer parts of Asia, Africa, and the Americas, with a high amount of diversity in Madagascar.Ahmed, Z.U. (ed.) (2008). Encyclopedia ...
'', ''
Brachiaria
''Urochloa'', commonly known as signalgrass,''Urochloa''. USDA PLANTS. is a
Urochloa
''Urochloa'', commonly known as signalgrass,''Urochloa''. USDA PLANTS. is a genus of plants in t ...
'' and '' Poecilostachys'' by its denser and thicker racemes.
The upper florets have oily appendages,
elaiosome
Elaiosomes ( ''élaion'' "oil" + ''sóma'' "body") are fleshy structures that are attached to the seeds of many plant species. The elaiosome is rich in lipids and proteins, and may be variously shaped. Many plants have elaiosomes that attract ...
s, which suggest seed dispersal by ants (
myrmecochory
Myrmecochory ( (sometimes myrmechory); from ("ant") and ''khoreíā'' ("circular dance") is seed dispersal by ants, an ecologically significant Myrmecophily, ant–plant Biological interaction, interaction with worldwide distribution. Most ...
), although this has not directly been observed.
''Chasechloa'' species are found in savanna, rocky outcrops or dry forest. They are restricted to the north-west of Madagascar.
The two species are:
*'' Chasechloa egregia'' (synonyms ''Panicum egregium'', ''Echinolaena boiviniana'' – this species is probably extinct; only one specimen from
Nosy Be
Nosy Be (; formerly Nossi-bé and Nosse Be, ) is a volcanic island off the northwest coast of Madagascar. Nosy Be is Madagascar's largest and busiest tourist destination. It has an area of , and its population was 109,465 according to the provisio ...