TAXONOMIC STUDY OF VENEGASIA (ASTERACEAE: HELENIEAE)

7 Pages·1992·3.5 MB·English

by  B L Turner

TAXONOMIC STUDY
OF VENEGASIA
(ASTERACEAE: HELENIEAE)
AND
TURNER
DAVID
ZIPPIN
B.L.
Department Botany
of
University Texas
of
TX
Austin, 78713, U.S.A.
ABSTRACT
A
The
genus
Venegasia is treated taxonomically. single species V. carpesioicks is recognized. It
largely confined to chaparral type vegetation of southern California and northern Baja
is
A
map
California, Mexico. showing distribution provided. Possible relationships of this
its is
well-marked, isolated, genus are discussed and concluded that, on morphological grounds,
it is
]
closest relatives armsianthtis and Amkastrum, small relictual genera of the southeastern
its d.i^
U.S.A. and Mexico,
respectively.
KEY WORDS:
Mexico
Asteraceae, Venegasia, Arnicastrum^Jamesianthus^
m
-
Venegasia carpesioides an attractive sufFruticose herb or subshrub 3 high.
is 1
common
name
has large yellow heads with prominent rays and has received the
It
Mc
Canyon Sunflower (Dale 1986, Auley 1985) andJesuit Sunflower (Beauchamp
The
1986). species seemingly confined to the chaparral vegetation of southern
is
common
and where
California northern Baja California reportedly in places,
it is
following
especially
fires.
De
was monotypic genus by CandoUe 1837 with
Venegasia established as a in
by by David
his description of V. carpesioides. It is typified material collected
De
Douglas in southern California; specimens from this collection were sent to
London (KEW).
Candolle by the Royal Botanic Gardens,
The name commemorates M.
generic Padre Venegas, an early Jesuit scholar
and Mexico While and
missionary writer of Pueblo, (Dale 1986). originally
De
correctly spelled Venegasia by Candolle, some workers have adopted the
Rydberg
spelling Venegazia 1914).
(e.g.,
Rydberg synonymy with
(1914) placed Parthenopsis rnarittma in Venegasia
new
carpesioides but proposed the species, V. deltoidea, the latter said to be
y
recognized by deltoid leaves cordate) and supposedly longer peduncles
its (vs.
mm
(mostly 10 long mm). Forms with deltoid leaves occur through-
ca. vs. ca. 5
V
out the range of and peduncle length likewise varies (mostly from
carpesioides^
1-6
cm). Recent workers have consistently recognized but a single
floristic
Munz
Wiggins do
species (e.g., 1974; 1980), as we. Indeed, since its description,
V
to our knowledge, no one has recognized ddtoidea as distinct.
223 -229.
SiDA 1992
15(2):
224 SiDA 1992
15(2):
L
Head
FKj. and floral parts o^Vemgasia carpesioides {Raven 1^438, TEX): upper head;
left,
upper right, ray lower disk lower
floret; left, floret; right, style.
VENEGASIA DC,
Prod. 6:43. 1837.
Panherwpsis Kellogg, Proc. Calif. Acad. 100. 1873- Based on Parthenopsh waritima Kellogg
5:
m
-
Suffruticosc perennial herbs orshrublets 3 high. Leaves mostly opposite,
1
deltoid-ovate to cordate, markedly petiolate, glabrous or nearly the margins
so,
axi
— cm 3-4
peduncles 10
1 long. Involucres seriate, the bracts subequal, the outer
loose
-
Ray
Receptacle convex, epaleate, minutely pubescent. 13
florets 34, pistillate,
the conspicuous, Disk numerous,
fertile, ligules yellow. florets yellow, the tube/
limb
ratio ca. 1/4, the tube densely glandular pubescent, 5-lobed. Anther
appendages Appendages
glandular. of style branches broadly obtuse in outline.
Achenes clavate, black, epappose. Base chromosome number, x =
striate, 19^
Type DC.
species, Venegasia
carpesioides
Turner and
Zippin, Vcnegasia 225
DC,
Venegasia CALIFORNIA:
carpesioides Prod. 43. 1837. w/o
6: T\te: specific
The number
833, D. Douglas 54 (holo'ptpe: P; isotype: NY!). date and collection
locality,
1
are as given on the isotype.
CALIFORNIA:
Parthenopsis mantimus Kellogg, Proc. Calif. Acad. Sci. 5: 101. 1873. Type:
W.G
Santa Rosa Island, 1872-73, .W. Harford {wolo-xyv^: CAS).
MEXICO.
Norte:
Venegasia deltoidea Rydb., N. Amer. Fl. 34, pt. 1 5 9 14. Type: Baj a Calif.
1
: -
"Sauzal", 7 Apr 1886, C.R. Orcutt (holotype: NY!). As originally described, Rydberg
s.n.
we
gave the locality as "Sangal" but the locality on the type specimen appears to read as give
mi
here. El Sauzal a fishing village located about 5 north of Ensenada, Mexico.
it is
A
and
single species, as described for the genus illustrationj Figure here
(cf. 1
&
Abrams
Figure 5319, Ferris I960).
Distribution and Ecology (Fig. Coastal ranges of California from southern
2):
Monterey County San Diego County and Channel Islands (Santa Rosa and
to
Mexico
3rN
o
Apr-J
GENERIC RELATIONSHIPS
When
was
originally proposed, Venegasia positioned in the tribe Senecionieae.
Bentham genus
(1873), largely because of epaleate receptacles, placed the in
its
Hoffmann
where was by
the Helenieae, subtribe Jaumeinae, retained
tribe
it
(1894).
Turner and Powell (1976), in their sweeping conspectus of the tribe Helenieae,
treated Venegasia rather indifferently, merely noting that appeared to belong,
it
along With. Jaumea, in the subtribe Jaumelnae (which they positioned in their
They and
newly erected tribe Coreopsideae). also noted that Venegasia Jaun7ea
number which two
seemed to have a of morphological features serve to relate the
genera both the Coreopsideae and Senecioneae Arnica and Whitneya).
to (e.g.
members
Stuessy (1976) accepted hoth. Jamnea and Venegasia as the only of his
7"
"group of the subtribe Coreopsidinae of the Helianrheae.
Robinson 98 in his account ofthe tribe Heliantheae (including Helenieae),
( 1 1 ),
in which 35 subtribes were recognized, daringly positioned Venegasia in the
subtribe Chaenactidinae, which also included Arnica and Whitneya and numerous
anomalous genera but positioned Jaurnea a
other rather Palafoxia), as
(e.g.
monotypic element of the subtribe Jaumeinae. Nevertheless, he singled out
among
Venegasia as "singularly distinctive" the subtribe Chaenactidinae in
having stalked glands on anthers.
its
x= &Kyhos
chromosome number (Raven 196l;Keil
has a base of 19
y^?;^^<:?j7^
&
Pinkava Other seemingly genera of the Heliantheae
1976). isolated, relictual,
such zsjanmea, Montanoa, and Podachaenium^ share this meiotic count but these
do not appear to relate closely to Venegasia. In contrast, within Robinson's concept
of the Chaenactidinae there are several genera with base numbers of x = 19,
226
SiOA 1992
15(2):
FIG. 2. Distribution of Wenegasia carpesioides in U.S.A. (California) and Mexico (inset).
Hidsm
Including Arnica, and Whitneya, none of which, in our opinion, appears
on
especially close to Venegasia morphological grounds.
Limited phytochemical examinations o( by Crawford and
Venegasia Stuessy
shown
(1981) have that does not possess anthochlors (chalcones and aurones),
it
which would tend to exclude from the tribe Coreopsideae, members of which
it
tend to exhibit such compounds. Nonetheless, these authors retained Venegasia
in that tribe, feeling that their absence in the latter was a loss phenomenon.
Geissman and Atala (1971) noted the occurrence of the sesquiterpene lactone
Turner and
Zippjn, Venegasia 227
Table Comparison of genera whose relationships are choughc to be closest to Vemgasia
1
.
Arnkastrum Jamesianthus
Venegasia
Habit
perennial herbs perennial herb perennial herb
stems suffruticose herbaceous herbaceous
Leaves
alternate above opposite opposite
strongly petiolate sessile sessile or subsessile
Capitulescence
(heads)
more
mostly single single 3 or
terminal terminal
axillary
Involucres
-
bracts in 2 3 distinct series ditto ditto
subequal and subscarious ditto ditto
outer series loose and enlarged ditto ditto
Receptacles
convex epalate ditto ditto
Ray
Florets
pistillate, fertile rays yellow ditto ditto
Disk
Florets
tube/limb
ratio
1/3-
1/4 1/2 1/3
moderately
tube densely sparsely
glandular pubescent glandular pubescent glandular pubescent
Anthers
appendages
glandular glandular glandular
Styles
branches
(apices)
broadly conical ditto ditto
shaft nodular ditto ditto
base
at
Achenes
ray florets
epappose pappose epappose
disk
florets
epappose 10 bristles oobristles
black, striate ditto ditto
Chromosome
No.
x=
X = 19 = 16
?
compound from
"eupatoriopicrin" in Venegasia, a previously reported only the
While
genera Eriophyllum, Eupatorium and Chaenactis. the Eupatorhmi connection
seems far-fetched, the Eriophyllum and Chaenactis connections are suggestive.
known
In summary, Venegasia does not appear to relate very closely to any
among
genera. After examining a large group of taxa, especially the Helenieae,
now (Kim
a tribe which the senior author accepts as largely natural and Turner,
in prep.), the genera he currently favors as closest to Venegasia on morphological
grounds Amicastrum both presumably genera
2Xt 2.vAjaniesianthus rare, relictual
^
which Robinson (1987) positioned in his subtribe Chaenactidinae. These several
228 SlDA 1992
15(2):
tcixa have a number of characters in common, indicated in table Whether
i\s 1.
these are properly positioned within Robinson's subtribe Chaenactidinae or
must more
better placed elsewhere await definitive studies, presumably using
DNA
data.
MEXICO.
Representative Specimens: Baja Calif. Del Norte: 6 mi S of San Vicente, Apr
1 1
1936, (NY); mi E of La Mision, 250 m, 30 Mar ^Moran 21715 (ARIZ, POM,
Ep/i}/^ 1^)15
s.fL
1
RSA, TEX, UC); canyon jnsc E of Buena Vista, 230 m, 2 Jun 1979, Moran 27342 (RSA); km
5
SE of Erendira, ca. 50 m, 7 Mar 1982, Monni 29996 (ARIZ); 9 mi S of Mancadero, 200 m,
ca.
2 Jun 985, Thorfie 61047 (RSA); Rancho Loma Linda, Las Animas: N-facing slopes, 200
ca.
1 1
m, Mar Thome 62290
1987, (RSA).
5
1
ACKN()WLniX}MF.NTS
This study based upon the examination of approximately 205 from
sheets
is
ARIZ
the following herbaria (numbers parenthesis specimens
in refer to loaned):
POM
TEX UC
RSA We
JEPS LL
and
(8), (53), (7), (37), (76), (1 (13). are
1),
grateful to the Directors of these institutions for the loans concerned. Barney
Lipscomb and anonymous
an reviewer provided helpful suggestions on an
earlier
draft.
REFERENCES
AhRAMS, and
L. R.S. Ferris. 960. Illustrated flora of the Pacific States Wvishingcon, Oregon, and
1
California. Stanford University Press, Stanford, California.
A
R.M.
BiiAUCiiAMP, 1986. flora of San Diego County, California. Sweetwater River Press,
National
City, California.
Bentham,
G. 1873. Notes on the classification, history and geographical distribution of
-
Comjxxsitae. Linn. Soc, Bot. 3:335 577.
J. 1
Crawford, D.J. and T.F. Stui-.ssy. 1981. The taxonomic significance of anthochlors in the
-
subcribe Coreopsidinac {Compositae, Helianthme). Anier. Bot. 68:107 117.
J.
Dale, N. 986. Flowering plants (the Santa Monica mountains, coastal and chaparral regions of
1
southern Cahfornia). Capra Press, Santa Barbara,
Calif,
Gi'isSMAN, T.A. and Atala. 197 Distribution ofeu[xitoriopicrin Compositae. Phytochem-
S. I. in
10:1075-
1077.
isrry
Hoi-FMANN, O.
1894. Tubuliforac-Heliantheae and Heleniaeae. In A. Engler and K. Prantl
-
Die
(Eds.): naturlichen Pflanzenfamilien 4(5):210 267.
Chromosome
Ki:iL, D.J. and V).}. Pinkava. 1976. counts and taxonomic notes for Compositae
from the United States and Mexico. Amer. Bot. 63:1393 - 1403.
J.
M.
McAl;ij:>; 1985. Wikltlowers of the Santa Monica Mountains. Canyon Publisliing Co.,
Canoga
Park, California.
A
MiiN/., P.A. 1974. Flora of Southern California, Univ. of California Press, Berkeley.
RYnai-.RG, P.A. 1914. Vemgazt<u N. Amer.
in Fl. 34, pt. 1:5.
A
Smi'I'II, C.F. 1976. floraof the Santa Barbara Region, California. Haagen Printing Co., Santa
Barbara, California.
T.F
S'ruE.ssY, 977. Heliantheae-systematic review. In leywood, V.H. J.B. iarborne and B.L.
1 I I
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p. 1
I
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New
York.
Turner and
Zippin, Venegasia 229
Turner, BX. and A.M. Powell. 1977. Helenicae-systematic review. In Heywood, V.H.,
J.B,
HarborneandB.L. Turner(Eds.): The biology and chemistry of the Composicae, 699-737.
p.
New
Academic
York.
Press,
Wiggins, 1980. Flora of Baja California, Stanford Univ. Press, Stanford, California.
I.L.