GLANDULARIA VERECUNDA (VERBENACEAE): SPECIES OR FRUIT-FORM?

2 Pages·2003·1.2 MB·English

by  B L Turner

GLANDULARIA VERECUNDA
(VERBENACEAE):
OR
FRUIT-FORM?
SPECIES
most Henrickson (2003) treated Glandularia
In the recent issue of Sida,
Umber
verecunda as a distinct species, this in sharp contrast to the present
quadrangulata (Hdler)
author's treatment of the taxon as but a fruit-form of G.
My
Umber
(Turner 1999). reason for this disposition followed several years of
work which could find no differences between the two hypothetical
in
field
I
species except that of a terminal appendage on the apex of G. verecunda, this
by Henrickson's
nicely illustrated Fig.
1.
Umber
Glandularia verecunda was proposed by the species
(1979),
first
name be derived from the Latin word verecundus or "bashful," presum-
said to
both herbarium
ably reference the taxon's proclivity to go unnoticed, in the
in to
matches
and in the Indeed, Umber's description of the taxon nearly that
field.
appendage on Turner
of G. quadrangulata, except for the terminal the fruit.
Umber
remarked verecunda
(1999) clearly noted that himself that G. is "indis-
meaning
from guadrangulata except the the pres-
tinguishable G. for seeds,"
an appendage on
ence of the nutlets.
Glandularia verecunda and quadrangulata are partially not largely
G.
if
by
sympatric over most of their distributions (not "largely allopatric" as stated
Henrickson, his use of the term sympatric apparently restricted to
After discussion "Of the three nomenclatural possibilities: being in-
a (1)
consequential forms of each other; (2) being geographical subunits of a species,
merely
one being separate species that
subspecies or varieties of species; or (3)
i.e.
co-occur in some areas," Henrickson surmises that the two taxa are distinct spe-
but can co-occur without interbreeding
very similar vegetatively
cies "that are
no intermediates have been found." Immediately thereafter, he concluded
as
with paragraph,
his discussion a terse as follows:
Henrickson comments further that "No plants have ever been discovered in
nature with nutlets intermediate in structure between those of G. quadra ngulata
and verecunda Furthermore, no hybridization has been done to
artificial
G.
...
determine would
the condition that be expressed hybrid." Needless
in a to say,
same comment
might most any
this be applied to albino form occurring in natu-
much
ral populations; nor does one spend effort seeking out an intermediate
forms polymorphism)
Fruit (or fruit in natural populations are relatively
common
some
rare, but are relatively in groups such as, for example, the genus
Vakrianclla (Valerianaceae). The interested reader referred to the work of
is
who
Ware
numerous
(1983), detailed fruit forms in Va IcrianeUa, several of which
m
had long been recognized as species. For those interested the genetics of such
work Xena
fruit types, the of de Enrech and Mathez (1998) might be consulted.
Fruit forms also occur in other Texas plants, for example in the genus
Thdcsperma The I
(Asteraceae). species cu rvicarpum Metchert, described
first
1963 from Burnett and Coleman was shown
in counties, Texas, subsequently
to
my
And
be but fruit-form (Greer
a 1997). likely that description
of
it is
Cynoglossum hintoniorum Turner (Boraginaceae) amounts no more than
to a
&
fruit-form of the widely distributed C.amahik Stapf Drumm. (Turner
1995).
Finally, it should be reemphasized that have called to the fore in the above-
I
mentioned
publication several populations quadrangularis which
of G. in
appendaged and nonappendaged
fruits occur intermixed. The two forms can
be separated only by the appendages on their nutlets, but have no trepidation
I
named
recognizing
in this fruit-form as a taxon, as follows:
Glandularia quadrangulata forma albida (Moldenke) comb, nov
Turner,
B.L.
Basionym: Verbena purmla forma albuia Moldenke, Phytologia
9:188. 1963.
Umber
synonym
forma
(1979 treated the as a of his concept of G. verecunda.
It is
unfortunate have up name
to to take the "albida" for this fruit-form, but the Code of
Botanical Nomenclature mandates use of the name rank having
eariiest in as
priority.
REFERENCES
GiUER, LF. 1997. Thelesperma curvicarpum (Asteraceae), an achene form populations
of
in
T.
simplicifolium var.simplicifolium and T.filifolium vaf.filifolium. Southw.Naturalist 42:242-244.
Hi NKicKsoN, H. 2003. Studies Glandularia (Verbencaeae): the Glandulaia quadrangulata
in
J.
complex. Sida 20:953-967.
Phytologia 79:306-308.
mi
979.The genus
R, R.E. 1 Glandularia (Verberlaceae) in North America. Syst. BtDt.4:72-102.
/ARF, D.M. 1983. Genetic fruit polymor phism North American
in ^alerianella
I
(Valerianaceae) and taxonomic
its implica tions. Syst. Bot. 8:33-44.
^-.ADEENREiCH,N.andJ.MAiHEz.l998.Genetic control of polymorphism the genus
fruit 1
ii
Fedia (Valerianaceae) in the light of din-lorphic and trimorphic popul ationsofF
99-2
pallescens. PI. Syst. Evol. 2 0:1 0.
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