''Dendrosenecio elgonensis'' is one of the giant groundsel of
East Africa
East Africa, also known as Eastern Africa or the East of Africa, is a region at the eastern edge of the Africa, African continent, distinguished by its unique geographical, historical, and cultural landscape. Defined in varying scopes, the regi ...
; this one is
endemic
Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...
to
Mount Elgon
Mount Elgon is an extinct shield volcano on the border of Uganda and Kenya, north of Kisumu and west of Kitale. The mountain's highest point, named "Wagagai", is located entirely within Uganda. . They used to be considered part of the genus ''
Senecio
''Senecio'' is a genus of flowering plants in the daisy family (Asteraceae) that includes ragworts and groundsels.
Variously circumscribed taxonomically, the genus ''Senecio'' is one of the largest genera of flowering plants.
Description
Mo ...
'' but recently have been reclassified to their own
genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
, ''
Dendrosenecio
''Dendrosenecio'' is a genus of flowering plants in the sunflower family. It is a segregate of ''Senecio'', in which it forms the subgenus ''Dendrosenecio''. Its members, the giant groundsels, are native to the higher-altitude zones of ten mou ...
''.
Description
''Dendrosenecio elgonensis'' can grow to 7 meters tall, with a trunk to 30 centimeters in diameter and
pith
Pith, or medulla, is a tissue in the stems of vascular plants. Pith is composed of soft, spongy parenchyma cells, which in some cases can store starch. In eudicotyledons, pith is located in the center of the stem. In monocotyledons, it ex ...
2.5 to 3 centimeters in diameter. ''D. elgonensis'' generally keeps its stem cloaked with its withered and decaying foliage (or with retained leaf-bases after fire) but eventually loses them as bark develops. "Periodic reproduction yields sparsely branched, spreading plants that rarely exceed five reproductive cycles."
Leaf surfaces are elliptic or heart-shaped, 97 centimeters long and 32 centimeters wide. The lower portion of the leaves are hairless except for along the mid-vein.
Flower heads
A pseudanthium (; : pseudanthia) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, composite flowers ...
are presented horizontally. 11 to 13, 24 millimeter long ray florets and 40 to 70 disc florets.
Distribution
Found on the slopes of Mount Elgon between 2750 and 4200 meters.
Infraspecific name
In botany, an infraspecific name is the scientific name for any taxon below the rank of species, i.e. an infraspecific taxon or infraspecies. The scientific names of botanical taxa are regulated by the ''International Code of Nomenclature for al ...
synonymy
The names for the giant groundsels have become somewhat confusing:
*''Dendrosenecio elgonensis'' (T.C.E.Fr.) E.B.Knox
**''Dendrosenecio elgonensis'' (T.C.E.Fr.) E.B.Knox subsp. ''barbatipes'' (Hedberg) E.B.Knox
***''
Dendrosenecio johnstonii'' (Oliv.) B.Nord. subsp. ''barbatipes'' (Hedberg) B.Nord.
***''Senecio barbatipes'' Hedberg
***''Senecio gardneri'' Cotton - non C.B.Clarke—''
nom. illegit.'' (ill.)
***''Senecio gardneri'' Cotton var. ''ligulatus'' Cotton & Blakelock
***''Senecio johnstonii'' Oliv. subsp. ''barbatipes'' (Hedberg) Mabb.
***''Senecio johnstonii'' Oliv. var. ''ligulatus'' (Cotton & Blakelock) C.Jeffrey
**''Dendrosenecio elgonensis'' (T.C.E.Fr.) E.B.Knox subsp. ''elgonensis''
***''
Dendrosenecio johnstonii'' (Oliv.) B.Nord. subsp. ''elgonensis'' (T.C.E.Fr.) B.Nord.
***''Senecio amblyphyllus'' Cotton
***''Senecio elgonensis'' T.C.E.Fr.
***''Senecio johnstonii'' Oliv. var. ''elgonensis'' (T.C.E.Fr.) Mabb.
References
elgonensis
Endemic flora of Kenya
Endemic flora of Uganda
Mount Elgon
Afromontane flora
Taxa named by Thore Christian Elias Fries
{{Senecioneae-stub