[Federal Register Volume 59, Number 163 (Wednesday, August 24, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-20789]
[[Page Unknown]]
[Federal Register: August 24, 1994]
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Part III
Department of the Interior
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Fish and Wildlife Service
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50 CFR Part 17
Endangered and Threatened Species: Final Five Plants From San
Bernardino Mountains, California; Texas Ayenia, etc.; Rules
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
RIN 1018-AC01
Endangered and Threatened Wildlife and Plants; Determination of
Endangered Status for the Plants Ayenia limitaris (Texas Ayenia) and
Ambrosia cheiranthifolia (South Texas Ambrosia)
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Final rule.
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SUMMARY: The Fish and Wildlife Service (Service) determines Ayenia
limitaris (Texas ayenia) and Ambrosia cheiranthifolia (South Texas
ambrosia) to be endangered species under the authority of the
Endangered Species Act (Act) of 1973, as amended. Texas ayenia is known
from a single population in Hidalgo County, Texas. South Texas ambrosia
has been verified recently from eight populations, four in Nueces
County, three in Kleberg County, and one overlapping both counties in
Texas. These species are threatened by habitat destruction and
fragmentation through alteration and conversion of native plant
communities to commercial uses; displacement by invasive nonnative
grasses; and low population numbers. This action will implement Federal
protection provided by the Act for Texas ayenia and South Texas
ambrosia. Critical habitat is not being designated.
EFFECTIVE DATE: September 23, 1994.
ADDRESSES: The complete file for this rule is available for inspection,
by appointment, during normal business hours at the Corpus Christi
Ecological Services Field Office, U.S. Fish and Wildlife Service, c/o
Texas A&M University at Corpus Christi, Campus Box 338, 6300 Ocean
Drive, Corpus Christi, Texas 78412.
FOR FURTHER INFORMATION CONTACT: Angela Brooks, at the above address
(telephone 512/994-9005; facsimile 512/994-8262).
SUPPLEMENTARY INFORMATION:
Background
Texas ayenia, a member of the cacao family, was first collected in
Hidalgo County, Texas, by C.G. Pringle in 1888, and was named
Nephropetalum pringlei by B.L. Robinson and J.M. Greenman in 1896. In
1960, Carmen Cristobal revised the genus Ayenia and described Ayenia
limitaris as a new species. The previously described Nephropetalum
pringlei was not mentioned in the revision. Prior to Cristobal's
description of Ayenia limitaris in 1960, South Texas specimens of this
species had been identified as A. berlandieri, a species of tropical
Mexico. In 1986, Laurence Dorr and Lisa Barnett transferred
Nephropetalum pringlei to the genus Ayenia and reduced it to synonymy
with Ayenia limitaris.
Texas ayenia is a pubescent subshrub approximately 60-150
centimeters (cm) (2-5 feet (ft)) tall, with alternate, simple leaves.
The cordate-based leaves are approximately 8 cm (3 inches (in)) long
and 3.5 cm (1.4 in) wide. The inflorescences are axillary, up to 4 per
node, with each inflorescence supporting two or more perfect flowers.
Flower color has been reported as green, pink, or cream. The fruit is a
5-celled, pubescent capsule approximately 8 millimeters (mm) (0.3 in)
long, with short, curved prickles (Damude and Poole 1990).
Texas ayenia occurs at low elevations in dense subtropical woodland
communities. Previous collectors have found the plant in openings
within chaparral and along the edges of thickets (Correll and Johnston
1979). The present site is a Texas Ebony-Anacua (Pithecellobium ebano-
Ehretia anacua) plant community located within the Arroyo Colorado
drainage. This area was once an active floodplain; however, the effect
of past flooding on Texas ayenia is unknown.
The Texas Ebony-Anacua plant community, which occurs on well
drained, but heavy soils on riparian terraces, once covered much of the
Rio Grande delta (Diamond 1990). Canopy cover is close to 95 percent in
this climax community type (Damude and Poole 1990). Associated species
include la coma (Bumelia celastrina), brasil (Condalia hookeri),
granjeno (Celtis pallida), and snake-eyes (Phaulothamnus spinescens).
The Texas Ebony-Anacua community grades into the Texas Ebony-Snake-eyes
community in the drier portions of the woodland habitat (Diamond 1990).
Both plant communities have been reduced to discontinuous fragments,
often surrounded by agricultural fields, pastures, or urban
development, and now cover less than 5 percent of their original area
(Jahrsdoerfer and Leslie 1988).
Texas ayenia occurred historically in Cameron and Hidalgo Counties
in the United States, and the states of Coahuila, Nuevo Leon, and
Tamaulipas in Mexico. The only recent collection in Mexico was from a
Tamaulipan population in 1981; however, the present status of this
population is unknown (Damude and Poole 1990). Texas ayenia has not
been relocated at any of the historic Cameron County locations since
the early 1960s. The status report by Damude and Poole (1990) noted a
1988 observation of six spindly plants at the Hidalgo County site, and
the following year only one individual was observed.
Searches were undertaken in 1990 and 1991 by a number of personnel
from the Service and Texas Parks and Wildlife Department, but no plants
were found. In 1992, Service personnel and Jim Everitt of the U.S.
Department of Agriculture located one plant at the Hidalgo County site.
In 1994, Joe Ideker (Native Plant Project, McAllen, Texas, pers.comm.
1994) located 20 additional plants at this site. This site, on private
property, is the only one recently verified for the species.
South Texas ambrosia was first collected in San Fernando,
Tamaulipas, Mexico, by Luis Berlandier in 1835, and was named Ambrosia
cheiranthifolia by A. Gray in 1859. The first United States collection
was made in 1932 by Robert Runyon from an area near Barreda (now
Russelltown) in Cameron County, Texas (Turner 1983).
South Texas ambrosia, a member of the aster family, is a
herbaceous, erect, silvery to grayish-green, rhizomatous perennial
plant, 10-30 cm (0.3-1.0 ft) tall. Its simple leaves are usually
opposite on the lower portion of the plant and alternate above. The
staminate flower heads are arranged in inconspicuous terminal racemes
5-10 cm (2-4 in) long. The pistillate flower heads are in small
clusters in the leaf axils just below the staminate racemes (Turner
1983). Due to its rhizomatous growth, a single plant may be represented
by hundreds of clonal stems.
South Texas ambrosia grows at low elevations in open clay-loam to
sandy-loam prairies and savannas. Much of the original native habitat
for South Texas ambrosia has been converted to agricultural fields,
improved pastures, or urban areas. Many savanna areas have been cleared
and planted to nonnative grasses, such as buffelgrass (Cenchrus
ciliaris), which outcompete and eventually displace much of the native
vegetation. Other potential prairie habitat may now be invaded by
thorny shrub and tree species as a result of fire suppression or
overgrazing. South Texas ambrosia does not appear to survive intensive
plowing, blading, or disking; however, some lesser soil disturbance may
enhance its growth. Associated native grasses found at the existing
sites include Texas grama (Bouteloua rigidiseta), buffalo grass
(Buchloe dactyloides), Texas speargrass (Stipa leucotricha), and tobosa
(Hilaria mutica). Invading nonnative grasses found at the sites include
buffelgrass, King Ranch bluestem (Bothriochloa ischaemum var.
songarica), bermuda grass (Cynodon dactylon), and St. Augustine grass
(Stenotaphrum secundatum) (U.S. Fish and Wildlife Service 1988).
Associated native woody species found scattered throughout the existing
sites include mesquite (Prosopis glandulosa), huisache (Acacia
smallii), huisachillo (Acacia schaffneri), brasil (Condalia hookeri),
granjeno (Celtis pallida), and lotebush (Ziziphus obtusifolia).
Historically, South Texas ambrosia occurred in Cameron, Jim Wells,
Kleberg, and Nueces counties in South Texas, and the state of
Tamaulipas in Mexico. The current status of any Mexican populations is
unknown. The historic populations in Cameron and Jim Wells counties
have not been relocated. Only one location noted in the status report
(Turner 1983) is known to be still extant. Three populations, two in
Nueces County, and one in Kleberg County, were discovered by Ruth
O'Brien (Texas A&M University at Corpus Christi, pers. comm. 1993).
Three Nueces County populations were discovered in 1992 and 1993 by
William Carr (Texas Parks and Wildlife Department, pers. comm. 1993).
The extant populations occur on private land, highway and railroad
rights-of-way, and the Kingsville Naval Air Station. Four historic
locations for South Texas ambrosia, one extirpated and three extant,
also support the endangered slender rush-pea (Hoffmannseggia tenella),
which was federally listed (50 FR 45624; November 1, 1985) because of
threats similar to those affecting South Texas ambrosia. One known
location for South Texas ambrosia also supports the endangered black
lace cactus (Echinocereus reichenbachii var. albertii), which was
federally listed (44 FR 61918; October 26, 1979) because of habitat
destruction and collecting threats.
Federal action on these species began as a result of section 12 of
the Endangered Species Act (16 U.S.C. 1531 et seq.), which directed the
Secretary of the Smithsonian Institution to prepare a report on those
plants considered to be endangered, threatened, or extinct in the
United States. This report, designated as House Document No. 94-51, was
presented to Congress on January 9, 1975. On July 1, 1975, the Service
published a notice in the Federal Register (40 FR 27823) accepting the
Smithsonian report as a petition within the context of section 4(c)(2)
of the Act, now section 4(b)(3)(A), and giving notice of its intention
to review the status of the plants named therein. Ambrosia
cheiranthifolia was included as endangered, and Ayenia limitaris, then
under the name Nephropetalum pringlei, was included as extinct in the
Smithsonian report and Service notice.
On June 16, 1976, the Service published a proposed rule in the
Federal Register (41 FR 24523) to determine approximately 1,700
vascular plant species to be endangered. Ambrosia cheiranthifolia was
included in the June 16, 1976, proposal. The 1978 amendments to the Act
required that all proposals over two years old be withdrawn, although a
one year grace period was given to proposals already over two years
old. In the December 10, 1979, Federal Register (44 FR 70796), the
Service published a notice withdrawing the June 16, 1976 proposal,
along with four other proposals that had expired.
A list of plants under review for listing as endangered or
threatened species was published in the December 15, 1980, Federal
Register (45 FR 82479). Ambrosia cheiranthifolia was included in
Category 2 of the list and Nephropetalum pringlei was included in
Category 1*. Category 2 species are those for which there is some
evidence of vulnerability, but for which there are insufficient data to
support listing proposals at the time. Category 1 species are those for
which the Service has on file substantial data on biological
vulnerability and threats to support the preparation of listing
proposals. Category 1* species are also those whose status in the
recent past is known to support listing, but that may have already
become extinct.
Section 4(b)(3)(B) of the Act requires the Secretary to make
certain findings on pending petitions within one year of their receipt.
Section 2(b)(1) of the 1982 amendments further requires that all
petitions pending on October 13, 1982, be treated as having been newly
submitted on that date. Because the 1975 Smithsonian report was
accepted as a petition, all of the plants contained therein, including
Nephropetalum pringlei (=Ayenia limitaris) and Ambrosia
cheiranthifolia, were treated as being newly petitioned on October 13,
1982. In each year from 1983 through 1992, the Service found that the
petitioned action was warranted, but listings of Ayenia limitaris and
Ambrosia cheiranthifolia were precluded by other listing actions of
higher priority in accordance with section 4(b)(3)(B)(iii) of the Act.
A status report on South Texas ambrosia was completed May 20, 1983
(Turner 1983). This report provided sufficient biological information
to justify proposing to list South Texas ambrosia as endangered.
Notices revising the 1980 list of plants under review for listing
as endangered or threatened species were published in the Federal
Register on September 27, 1985 (50 FR 39526) and February 21, 1990 (55
FR 6184). Nephropetalum pringlei (=Ayenia limitaris) was included in
Category 2 and Ambrosia cheiranthifolia was included in Category 1 of
these notices.
A status report on Texas ayenia was completed December 1, 1990
(Damude and Poole 1990). This report provided sufficient biological
information to justify proposing to list Texas ayenia as endangered.
The proposed rule to list Texas ayenia and South Texas ambrosia as
endangered was published in the Federal Register on August 5, 1993 (58
FR 41696). Publication of that proposed rule constituted the final one-
year finding for these species.
Summary of Comments and Recommendations
In the August 5, 1993, proposed rule and associated notifications,
all interested parties were requested to submit factual reports or
information that might contribute to the development of a final rule.
Appropriate Federal and State agencies, county governments, scientific
organizations, and other interested parties were contacted and
requested to comment. Newspaper notices, which invited general public
comment, were published in the Monitor (McAllen, Texas) and the Corpus
Christi Caller Times (Corpus Christi, Texas) on August 20, 1993, and
August 17, 1993, respectively. Three comments were received. Two
commenters supported the listing; one commenter was neutral. Issues
raised by commenters are discussed below.
Issue 1--The proposed rule fails to note industrial development as
one of the major causes of habitat loss for rare plants.
Service Response--The Service has included industrial development
as a threat in this final rule.
Issue 2--From the proposed rule discussion of the taxonomic history
of Texas ayenia it is unclear why the correct scientific name is not
Ayenia pringlei because Nephropetalum pringlei is an earlier name than
Ayenia limitaris.
Service Response--Dorr and Barnett (1986) concluded that the
correct placement of this species was within the genus Ayenia. However,
the specific epithet pringlei had already been used for another species
in Ayenia. So, although the name Nephropetalum pringlei is earlier than
Ayenia limitaris, the use of pringlei as the specific epithet would
create two species with the same name, which is not allowed by the
rules of botanical nomenclature.
Issue 3--Records for South Texas ambrosia indicate 25 occurrences,
with 17 of them extant. Records show 5 occurrences in Nueces County, 11
in Kleberg County, and 1 occurrence overlapping in both counties.
Service Response--The discrepancy between the number of occurrences
given in the comment letter and the number of populations reported in
the proposed rule is due to the Service considering several of the
occurrences to be close enough together to be part of a single
population.
Issue 4--One commenter noted that if individuals of either species
were present on floodways the plants would not obstruct flows,
therefore, vegetation maintenance in the floodways would not affect the
plants.
Service Response--While individual plants may not obstruct flood
flows, the densely wooded community in which Texas ayenia occurs would.
Should this densely wooded community be present, or new areas of
appropriate habitat be added to the floodway system, Federal agencies
would need to determine the species' absence before conducting floodway
vegetation maintenance.
Issue 5--One commenter provided an assessment of the threats of
habitat destruction, fragmentation, and loss of genetic variability on
both species.
Service Response--The Service appreciates this information.
Issue 6--One commenter offered to coordinate with the Service to
protect the species and their habitats.
Service Response--The Service appreciates the need to cooperate and
coordinate with Federal, state, and local agencies, private
organizations, and citizens to protect and recover these species.
Summary of Factors Affecting the Species
After a thorough review and consideration of all information
available, the Service has determined that Texas ayenia and South Texas
ambrosia should be classified as endangered species. Procedures found
at section 4(a)(1) of the Act and regulations (50 CFR part 424)
promulgated to implement the listing provisions of the Act were
followed. A species may be determined to be an endangered or threatened
species due to one or more of the five factors described in section
4(a)(1). These factors and their application to Ayenia limitaris
Cristobal (Texas ayenia) and Ambrosia cheiranthifolia Gray (South Texas
ambrosia) are as follows:
A. The present or threatened destruction, modification, or
curtailment of its habitat or range. Habitat destruction is the primary
threat to Texas ayenia and South Texas ambrosia. The past and current
practices of converting native South Texas brush and woodlands to
agricultural fields, improved pastures, and urban areas, or clearing
brush and woodlands for urban water development, industrial
development, or flood control have destroyed 95 percent of this native
vegetation (Jahrsdoerfer and Leslie 1988). Most native Texas Gulf Coast
prairies have been converted to agricultural fields or improved
pastures. The amount of conversion of these plant communities in Mexico
is similar though not quantified. The remaining remnant native prairie,
brush, and woodland tracts are often surrounded by agricultural fields,
pastures, or urban development. These modified habitats pose potential
threats to the native areas through agricultural chemical drift from
aerial spraying; chemical runoff following rains; invasion of nonnative
grasses such as buffelgrass, guineagrass (Panicum maximum), King Ranch
bluestem, and Angleton bluestem (Dichanthium aristatum); and trampling
and possible collection pressures due to easy accessibility from nearby
urban areas. The few remaining populations of the species are
vulnerable to extinction if any of their remaining habitat is modified.
Even roadside remnants of native vegetation in South Texas are
often bladed, or plowed and seeded with exotic grasses such as
buffelgrass and King Ranch bluestem. Herbicides are often used to
control vegetation around signs, guard rails, and bridge abutments, and
to kill shrubby vegetation encroaching on the right-of-way. Due to the
rarity of Texas ayenia and South Texas ambrosia, the likelihood they
will be directly impacted by roadway maintenance is small, but almost
any impact could lead to extinction of either species.
B. Overutilization for commercial, recreational, scientific, or
educational purposes. No commercial trade is known for either of these
species; however, the potential exists for vandalism and collection.
Listing these species, with the resulting publicity, will highlight
their rarity and may increase their attractiveness to some collectors.
Excessive recreational or scientific use is not known or anticipated
for either species.
C. Disease or predation. Although the Texas ayenia population has
shown no evidence of disease or predation, Cristobal (1960) notes the
floral buds of Ayenia species are often deformed by Hymenopteran
larvae. Cristobal also notes Ayenia fruits can be deformed by Dipteran
larvae thus inhibiting seed release. No evidence of grazing or browsing
has been observed for Texas ayenia.
No threats of disease or predation are known for South Texas
ambrosia; however, damage to stems and rhizomes is possible in
situations of severe trampling or grazing.
D. The inadequacy of existing regulatory mechanisms. Presently,
neither species is protected by Federal or State law. Listing under the
Act would provide protection for these species.
E. Other natural or manmade factors affecting its continued
existence. With only one known verified population, Texas ayenia may
have low genetic variability, which could limit its ability to adapt to
environmental changes. It is unknown whether past flooding created or
maintained habitat for Texas ayenia. However, since the present
population occurs within a previously active drainage of the Arroyo
Colorado (Damude and Poole 1990), a flood could negatively impact the
species. Observers have noted that the population declined during the
recent drought in the Lower Rio Grande Valley (J. Everitt, U.S.
Department of Agriculture, pers. comm. 1992). The extreme rarity of
this species makes it vulnerable to extinction from any number of
chance events.
South Texas ambrosia may also be vulnerable to extinction due to
lowered genetic variability. Populations are clonal, so despite having
many stems, the populations may actually represent very few genetically
different individuals. It has been noted that species like South Texas
ambrosia that were once more widespread, but are now reduced to low
numbers, may be more vulnerable to the detrimental effects of lowered
genetic diversity than species that were always rare (Huenneke 1991).
The Service has carefully assessed the best scientific and
commercial information available regarding the past, present, and
future threats faced by these species in determining to make this rule
final. Based on this evaluation, the preferred action is to list Texas
ayenia and South Texas ambrosia as endangered. The status of endangered
is appropriate because of these species' limited distribution, low
population numbers, and imminent threats of habitat destruction.
Critical Habitat
Critical habitat is defined in section 3 of the Act as--(i) The
specific areas within the geographic area occupied by a species, at the
time it is listed in accordance with the Act, on which are found those
physical features (I) Essential to the conservation of the species and
(II) that may require special management consideration or protection
and; (ii) specific areas outside the geographic areas occupied by a
species at the time it is listed, upon a determination that such areas
are essential for the conservation of the species. ``Conservation''
means the use of all methods and procedures needed to bring the species
to the point at which listing under the Act is no longer necessary.
Section 4(a)(3) of the Act, as amended, and implementing
regulations (50 CFR 424.12) require that, to the maximum extent prudent
and determinable, the Secretary designate critical habitat at the time
a species is determined to be endangered or threatened. The Service
finds that designation of critical habitat is not prudent for Texas
ayenia and South Texas ambrosia at this time. Service regulations (50
CFR 424.12(a)(1)) state that designation of critical habitat is not
prudent when one or both of the following situations exist--(1) The
species is threatened by taking or other human activity, and
identification of critical habitat can be expected to increase the
degree of threat to the species, or (2) such designation of critical
habitat would not be beneficial to the species.
As discussed under Factor B in the ``Summary of Factors Affecting
the Species,'' Texas ayenia and South Texas ambrosia are potentially
threatened by taking or vandalism. These activities are difficult to
prevent and only regulated by the Act with respect to plants in cases
of (1) Removal and reduction to possession of listed plants from lands
under Federal jurisdiction, or their malicious damage or destruction on
such lands; and (2) removal, cutting, digging up, or damaging or
destroying in knowing violation of any State law or regulation,
including State criminal trespass law. Such provisions are difficult to
enforce, and publication of critical habitat descriptions and maps
would make Texas ayenia and South Texas ambrosia more vulnerable to
collecting or vandalism and increase enforcement problems. All involved
parties and principal landowners have been notified of the location and
importance of protecting these species' habitat. Protection of these
species' habitat will be addressed through the recovery process and
through section 7 consultation. Therefore, it would not now be prudent
to determine critical habitat for Texas ayenia and South Texas
ambrosia.
Available Conservation Measures
Conservation measures provided to species listed as endangered or
threatened under the Endangered Species Act include recognition,
recovery actions, requirements for Federal protection, and prohibitions
against certain practices. Recognition through listing encourages and
results in conservation actions by Federal, State, and private
agencies, groups, and individuals. The Act provides for possible land
acquisition and cooperation with the States and requires that recovery
actions be carried out for all listed species. The protection required
of Federal agencies and the prohibitions against certain activities
involving listed plants are discussed, in part, below.
Section 7(a) of the Act, as amended, requires Federal agencies to
evaluate their actions with respect to any species that is proposed or
listed as endangered or threatened and with respect to its critical
habitat if any is being designated. Regulations implementing this
interagency cooperation provision of the Act are codified at 50 CFR
part 402. Section 7(a)(2) requires Federal agencies to ensure that
activities they authorize, fund, or carry out are not likely to
jeopardize the continued existence of a listed species or to destroy or
adversely modify its critical habitat. If a Federal action may affect a
listed species or its critical habitat, the responsible Federal agency
must enter into formal consultation with the Service.
Some Federal actions that may affect Texas ayenia or South Texas
ambrosia include brush clearing for flood control by the International
Boundary and Water Commission, management recommendations to landowners
by the Soil Conservation Service for activities funded by the
Agricultural Stabilization and Conservation Service, and agricultural
pesticide registration by the Environmental Protection Agency.
Additionally, a population of South Texas ambrosia occurs on Kingsville
Naval Air Station and may be affected by maintenance or construction
activities at this facility.
The Act and its implementing regulations set forth a series of
general prohibitions and exceptions that apply to all endangered
plants. All prohibitions of section 9(a)(2) of the Act, implemented by
50 CFR 17.61, apply. These prohibitions, in part, make it illegal for
any person subject to the jurisdiction of the United States to import
or export, transport in interstate or foreign commerce in the course of
a commercial activity, sell or offer for sale in interstate or foreign
commerce, or to remove and reduce these species to possession from
areas under Federal jurisdiction. In addition, for plants listed as
endangered, the Act prohibits malicious damage or destruction on
Federal lands and removal, cutting, digging up, or damaging or
destroying of such plants in knowing violation of any State law or
regulation, including State criminal trespass law. Certain exceptions
to the prohibitions apply to agents of the Service and State
conservation agencies.
The Act and 50 CFR 17.62 and 17.63 also provide for the issuance of
permits to carry out otherwise prohibited activities involving
endangered plants under certain circumstances. Such permits are
available for scientific purposes and to enhance the propagation and
survival of the species. It is anticipated that few trade permits would
ever be sought or issued because the species are not in cultivation or
common in the wild. Requests for copies of the regulations regarding
listed species and inquiries regarding prohibitions and permits may be
addressed to U.S. Fish and Wildlife Service, Division of Endangered
Species/Permits, P.O. Box 1306, Albuquerque, New Mexico 87103
(telephone 505/766-3972; facsimile 505/766-8063).
National Environmental Policy Act
The Fish and Wildlife Service has determined that Environmental
Assessments and Environmental Impact Statements, as defined under the
authority of the National Environmental Policy Act of 1969, need not be
prepared in connection with regulations adopted pursuant to section
4(a) of the Endangered Species Act of 1973, as amended. A notice
outlining the Service's reasons for this determination was published in
the Federal Register on October 25, 1983 (48 FR 49244).
References Cited
Cristobal, C.L. 1960. Revision del genero Ayenia L. (Sterculiaceae).
Opera Lilloana 4:1-230.
Damude, N., and J. Poole. 1990. Status report on Avenia limitaris.
U.S. Fish and Wildlife Service, Albuquerque, New Mexico.
Diamond, D. 1990. Plant communities of Texas (series level). Texas
Parks and Wildlife Department, Austin, Texas.
Dorr, L.J., and L.C. Barnett. 1986. The identity of Nephropetalum
(Sterculiaceae). Taxon 35(1):163-164.
Huenneke, L.F. 1991. Ecological implications of genetic variation in
plant populations. In D. Falk and K. Holsinger, eds. Genetics and
Conservation of Rare Plants. Oxford University Press, New York.
Jahrsdoerfer, S.E., and D.M. Leslie, Jr. 1988. Tamaulipan brushland
of the Lower Rio Grande Valley of South Texas: description, human
impacts, and management options. U.S. Fish and Wildlife Service,
Biol. Rep. 88(36). 63 pp.
Turner, B.L. 1983. Status report on Ambrosia cheiranthifolia. U.S.
Fish and Wildlife Service, Albuquerque, New Mexico.
U.S. Fish and Wildlife Service. 1988. Slender rush-pea
(Hoffmannseggia tenella) recovery plan. U.S. Fish and Wildlife
Service, Albuquerque, New Mexico. 38 pp.
Author
The primary author of this final rule is Angela Brooks (see
ADDRESSES section).
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, and Transportation.
Regulation Promulgation
Accordingly, part 17, subchapter B of chapter I, title 50 of the
Code of Federal Regulations, is amended as set forth below:
PART 17--[AMENDED]
1. The authority citation for part 17 continues to read as follows:
Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C.
4201-4245; Pub. L. 99-625, 100 Stat. 3500; unless otherwise noted.
2. Section 17.12(h) is amended by adding the following, in
alphabetical order under the plant families indicated, to the List of
Endangered and Threatened Plants to read as follows:
Sec. 17.12 Endangered and threatened plants.
* * * * *
(h) * * *
----------------------------------------------------------------------------------------------------------------
Species
---------------------------------------- Historic range Status When listed Critical Special
Scientific name Common name habitat rules
----------------------------------------------------------------------------------------------------------------
* * * * * * *
Asteraceae--Aster
family:
* * * * * * *
Ambrosia South Texas U.S.A. (TX), E 547 NA NA
cheiranthifoli ambrosia. Mexico.
a.
* * * * * * *
Sterculiaceae--Caca
o family:
Ayenia Texas Ayenia...... U.S.A. (TX), E 547 NA NA
limitaris. Mexico.
* * * * * * *
----------------------------------------------------------------------------------------------------------------
Dated: July 11, 1994.
Mollie H. Beattie,
Director, Fish and Wildlife Service.
[FR Doc. 94-20789 Filed 8-23-94; 8:45 am]
BILLING CODE 4310-55-P
