Christoph Oberprieler The Systematics of Anthemis L. - Herbmedit.org

24 Oberprieler: Anthemis in N Africa
base are found in all perennial and most annual species, they tend to be absent in Anthemis
boveana, A. chrysantha, and A. gharbesis of A. ser. Chrysanthae, and in most of the
members of A. ser. Bourgaeinianae.
Leave texture is usually herbaceous, but succulent leaves are common in species from
maritime habitats (e.g. Anthemis maritima, A. secundiramea, A. chrysantha, A. mauritiana).
Dimensions of leaves are variable and depend on growth conditions. However, in the
Anthemis pedunculata - A. punctata group of species they may help in the determination
of taxa: basalleaves in A. pedunculata are usually up to 45(-75) mm long and up to 20(-30)
mm wide, those of A. punctata are conspicuously longer (up to 115 mm) and wider (up to
53 mm). A. abylaea is also characterized by rather long (up to 80 mm) and wide (up to 35
mm) basalleaves.
The dissection of leaf blades proves to be taxonornically relevant, its degree depending
on the position of the leaf on the stem. As a rule, the most basaI leaves are less strongly
dissected than the lower cauline ones, and further upward leaf dissection is again gradually
reduced. Therefore, differences in Ieaf dissection are particularly important in the lower
cauline leaves. In most N African Anthemis taxa the lower leaves are pinnatisect with
primary lobes cut right to the axis, but in A. maritima subsp. bolosii and some plants of
A. punctata subsp. kabylica they are pinnatifid or pinnatipartite.
2- to 3-pinnatisect or -pinnatipartite leaves are found in most species. The shape of ultimate
leaf segments may vary within taxa from broadly triangular to narrowly elliptical or
even linear, and their dimensions also varies. No clear-cut discontinuities between taxa
could be observed, but some tendencies are sufficiently marked to be used as distinguishing
features. For example, Anthemis pedunculata usually has 1.0-5.5 mm long and 0.3-1.8
mm wide ultimate leaf segments, but those of A. punctata (1.4-9.0 mm x 0.6-2.3 mm) and
A. eretica varo columnae (1.7-20.0 mm x 0.6-2.0 mm) are considerably larger. In most
species, ultimate leaf segments end in a mucro of 0.1-0.3 mm length. No mucronate leaf
segments were observed in some populations of A. secundiramea.
Peduncles
In the present study, the peduncle is defined as the distaI portion of the stem subtending
a capitulum, from the most distaI leaf on this axis to the base of the involucre. While
peduncle length was found to be very variable in all species examined and therefore unhelpful
for the characterisation of taxa, the inflation of peduncles at maturity proved to be
relevant. In the N Mrican representatives of Anthemis subg. Cota (A. austriaca) and of
A. sect. Hiorthia the peduncles usually remain slender or become only slightly inflated at
maturity. In A. sect. Anthemis and sect. Maruta, strongly inflated peduncles are found in
A. arvensis subsp. incrassata of A. ser. Anthemis and in A. chrysantha of A. ser. Chrysanthae.
In A. secundiramea of A. ser. Secundirameae, this character is used to distinguish the
two N African varieties of that species, varo secundiramea with and varo cossyrensis without
conspicuously inflated peduncles. A further representative of this series, A. ubensis,
and some populations of A. glareosa al so show incrassate peduncles. In contrast, all representatives
of A. ser. Bourgaeinianae have peduncles remaining slender at maturity. In
A. sect. Maruta, this character can be used to distinguish A. cotula (slender peduncles)
from A: pseudocotula (inflated peduncles).