(DRAFT) - Taxonomy
Species CACTUS, HEDGEHOG, LLOYD'S
Species Id ESIS702015
Date 13 MAR 96
TAXONOMY
NAME - CACTUS, HEDGEHOG, LLOYD'S
OTHER COMMON NAMES - CACTUS, HEDGEHOG and LLOYD'S
ELEMENT CODE -
CATEGORY - Angiosperm
PHYLUM AND SUBPHYLUM - MAGNOLIOPHYTA,
CLASS AND SUBCLASS - MAGNOLIOPSIDA,
ORDER AND SUBORDER - CARYOPHYLLALES,
FAMILY AND SUBFAMILY - CACTACEAE,
GENUS AND SUBGENUS - ECHINOCEREUS,
SPECIES AND SSP - LLOYDII,
SCIENTIFIC NAME - ECHINOCEREUS LLOYDII
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
Lloyd's Hedgehog Cactus
Echinocereus lloydii Britt. and Rose
KINGDOM: Plant GROUP: Angiosperm
DIVISION: Magnoliophyta CLASS: Magnoliopsida
ORDER: Caryophyllales FAMILY: Cactaceae
Plants with one stem or several in a clump 15 to 20 cm high, 30
cm or more in diameter; stems green, cylindroid, 15 to 30 (-60, 01)
cm long, 7.5 to 11.5 cm in diameter; ribs 11 to 13 in number,
tuberculate; areoles circular, 6 to 16 mm apart; spines are partially
obscuring the stem, red with a gray surface coating in appearance,
straight and acicular; central spines number 2 to 8 per areole,
spreading, to 12 mm long; radial spines number 8 to 17 per areole,
spreading irregularly, to 15 (22,02) mm long; flower is 6 to 7.5 cm
long, 5 to 9 cm in diameter, with much variation in color; the outer
floral bracts have purplish midribs and lavender margins, narrowly
elliptic-oblong, 3 cm long, 6 mm broad, obtuse, mucronulate, undulate;
inner floral bracts are lavender or magenta to orangish red, cuneate-
lanceolate, 4 cm long, 1.2 cm broad, rounded, mucronulate, entire;
filaments 6 to 9 mm long; anthers variable from yellow to pink, 1 mm
long; the style is 25 mm long; stigmas are green, 9 to 20 lobes, 9 mm
Taxonomy - 1 (DRAFT) - Taxonomy
Species CACTUS, HEDGEHOG, LLOYD'S
Species Id ESIS702015
Date 13 MAR 96
long; the fruit is green tinged with pink or orange, ovoid, 25 to 30
(-50, 02) mm long, 12 to 20 mm in diameter, with white spines about
1.5 mm long; the seeds are black, strongly papillate, 1 mm long, about
1.5 mm broad. Chromosome number n=22 (02,03,04,05,06,07; Koole 45,
UTEP).
According to Weniger, the Eddy County, New Mexico populations
are erroneously identified (02). However, Benson, Zimmerman and
Knight feel these specimens to be correctly identified as Echinocereus
lloydii (03,08,09).
Backeberg placed E. lloydii as a variety of E. roetteri (05).
Zimmerman thinks that roetteri might be the valid name for this taxon
(08). Zimmerman also feels that Benson's interpretation of E. lloydii
is too restricted, and that some of the localities asscribed to E.
pectinatus var. minor actually represent E. lloydii (08). In the
European horticultural literature, the Chihuahuan population of E.
lloydii is being called E. pectinatus "var. rectispinus", according to
Zimmerman (08).
Due to the morphological variability within the species, both
Knight and Zimmerman have suggested that the taxon may be of hybrid
origin (between E. dasyacanthus and E. triglochidiatus) but stabilized
reproductively (08,09). The Pecos County populations intergrade with
E. dasyacanthus, resulting in a spectacular array of different flower
colors (08).
According to Benson, an invalid name of uncertain application,
but perhaps referable to E. lloydii, is E. viridiflorus var.
intermedius (03). However, Leuck submerges this name in E.
viridiflorus var. cylindricus (10).
The lectotype (F.E. Lloyd s.n.) is housed at the U.S. National
Herbarium (US 691964) (03). Other specimens may be found at the
following herbaria: NY, POM, UNM, and UTEP.
Descriptions, photographs, and/or illustrations are found in
several works: (01,02,03,04,05,06,07).
Taxonomy - 2 (DRAFT) - Status
Species CACTUS, HEDGEHOG, LLOYD'S
Species Id ESIS702015
Date 13 MAR 96
STATUS
Coded Status
E: Federal Endangered
Commercial
Non-consumptive recreational
Ornamental
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
The Lloyd's hedgehog cactus (Echinocereus lloydii) has been
designated an Endangered species pursuant to the Endangered Species
Act of 1973 (50 CFR 17.12; P.L. 93-205, 87 Stat. 884; 16 U.S.C.
1531-1540), as amended. The species has this status wherever found
including the States of New Mexico and Texas. Populations of this
species which occur in Mexico are not listed pursuant to the
Endangered Species Act.
Removal and reduction to possession of any Federally listed plant
from an area under Federal jurisdiction is unlawful (50 CFR 17.61 and
17.71).
This species is protected by the Lacey Act (P.L. 97-79, as
amended; 16 U.S.C. 3371 et seq.) which makes it unlawful to possess
any wild plant (including roots, seeds, and other parts) within U.S.
territorial or special maritime jurisdiction (as defined in 18 U.S.C.
7); or to import, export, transport, sell, receive, acquire, or
purchase in interstate or foreign commerce any wild plant (including
roots, seeds, and other parts) taken, possessed, transported, or sold
in violation of any State law or regulation. It is also unlawful to
import, export, transport, sell, receive, acquire, or purchase any
wild plant (including roots, seeds, and other parts) taken or
possessed in violation of any U.S. law, treaty, or regulation or in
violation of Indian tribal law.
RESPONSIBLE FEDERAL AGENCIES:
USFWS -Responsible for the management/recovery, listing, and
law enforcement/protection of this species.
BLM -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public land under their control (43 CFR 4140). Also
responsible for management/recovery on Bureau of Land
Management lands.
DOD -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public land under their control. Also responsible for
management/recovery on Department of Defense lands.
Status - 1 (DRAFT) - Status
Species CACTUS, HEDGEHOG, LLOYD'S
Species Id ESIS702015
Date 13 MAR 96
NPS -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public lands under their control. Also responsible
for conservation (Nat. Park System Organic Act - 16
U.S.C. 1, 2-3)/management/recovery on National Park
Service lands. Taking, possessing, or disturbing of
Federally listed species is prohibited on NPS lands
(36 CFR 2.1, 2.2, and 2.3).
USFS -Responsible for the law enforcement/protection of this
species with applicable State and Federal laws on
public lands under their control. Also responsible
for management/recovery on Forest Service lands. The
Forest Service is responsible for integrating
management, protection, and conservation of Federally
listed species into the Forest Planning process
(36 CFR 219.19 and 219.20).
All Federal agencies have responsibility to ensure that any
action authorized, funded, or carried out by that agency is not likely
to jeopardize the continued existence of the species or result in the
destruction or adverse modification of Critical Habitat (50 CFR 402),
and to utilize their authorities to carry out programs for the
conservation of the species.
STATE STATUSES AND LAWS:
STATE: New Mexico
DESIGNATED STATUS: Protected
ADMINISTRATIVE AGENCY: New Mexico Department of Natural
Resources
STATE STATUTE: New Mexico Statutes Annotated 1978, Endangered
Plant Species Program
STATE: Texas
DESIGNATED STATUS: Endangered
ADMINISTRATIVE AGENCY: Texas Parks and Wildlife Department
STATE STATUTE: Chapter 88 of the Texas Parks and Wildlife Code,
Texas Parks and Wildlife Rules for Protected,
Threatened and Endangered Native Plant Species,
Sec 57.401-57.413
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
This species is listed in Appendix I of CITES.
ECONOMIC STATUSES:
This species has horticultural value and is commercially
available from cactus and succulent dealers. It's rarity makes it
particularly desirable to collectors. It has value as a component of
New Mexico and Texas's natural heritage of biotic diversity.
75/07/01:40 FR 27823/27924 - Notice of review
76/06/16:41 FR 24523/24572 - Proposed Endangered
Status - 2 (DRAFT) - Status
Species CACTUS, HEDGEHOG, LLOYD'S
Species Id ESIS702015
Date 13 MAR 96
79/10/26:44 FR 61916/61917 - Listing as Endangered
85/07/22:50 FR 29901/29909 - Five year review
Status - 3 HABITAT ASSOCIATIONS
HABITAT - TERRESTRIAL
TERRESTRIAL
LAND USE -
Transportation, communications, and Util
Shrub and Brush Rangeland
Orchards, Groves, Vineyards, Nurseries,
Bare Exposed Rock
COMMENTS ON HABITAT ASSOCIATIONS -
Echinocereus lloydii occurs in the shrub and brush rangeland of
the Chihuahuan Desert. A major highway (IH 10, with a associated
fenceline) runs through part of the habitat in Pecos County, TX.
Echinocereus lloydii grows on sandy, gravelly, or rock soils on slopes
and hillsides, as well as on bare rock ledges (02,03), and on
fine-textured alluvial floors (08). The rock or gravel is usually
limestone, occasionally with weathered metamorphic rock. The climate
is hot (64 to 68 degrees F mean annual temperature) and arid (8 to 14
inches mean annual precipitation) (11). The elevation varies between
900 and 1650 meters (03). Ussually E. lloydii grows on open, fully
exposed sites with very scattered forbs, grasses and brush (02).
Sometimes it occurs in dense mesquite scrub among tall grasses (08).
Some associates are Agave lecheguilla (02), Prosopis glandulosa
(Weniger 183, UNM), Opuntia engelmannii, O. phaeacantha, O. imbricata,
O. leptocaulis, Echinocereus dasyacanthus, E. stramineus, Coryphantha
vivipara var. radiosa, Ferocactus hamatacanthus var. hamatacanthus,
and Echinocactus horizonthalonius (12). A large area of scrub is
visible from IH 10, not far east of Tunas Springs, has been cleared
and might be a vineyard; more such developments might be forthcoming)
(08). See the field "N-BIOLOGY" (Ecological/Edaphic Factors) for
specific geological and soil associations.
In Texas, one population of Lloyd's hedgehog cactus occurs in
northeastern Culberson County in the Guadalupe Mountains National Park
at the trailhead to the Williams Ranch at Highway 62-180.
Habitat Associations - 1 (DRAFT) - Food Habits
Species CACTUS, HEDGEHOG, LLOYD'S
Species Id ESIS702015
Date 13 MAR 96
FOOD HABITS
TROPHIC LEVEL -
AUTOTROPH
Food Habits - 1 (DRAFT) - Environment Associations
Species CACTUS, HEDGEHOG, LLOYD'S
Species Id ESIS702015
Date 13 MAR 96
ENVIRONMENTAL ASSOCIATIONS
G = General A = Adult
LIM = Limiting RA = Resting Adult
J = Juvenile FA = Feeding Adult
RJ = Resting Juvenile BA = Breeding Adult
FJ = Feeding Juvenile P = Pupae
L = Larvae E = Egg
RL = Resting Larvae
FL = Feeding Larvae
LIFESTAGE ENVIRONMENTAL ASSOCIATIONS
G Terrestrial Features: Cliffs/ledges
G Availability of fence rows: roadside ditches and grassy
G
G
G
G
G
G
Environment Associations - 1 (DRAFT) - Life History
Species CACTUS, HEDGEHOG, LLOYD'S
Species Id ESIS702015
Date 13 MAR 96
LIFE HISTORY
HABIT:
Succulent (01,02,03,04,05,06,07).
LIFE CYCLE:
Perennial (02,03,04,05,06,07,08).
TYPE OF REPRODUCTION:
Sexual (02,08).
REPRODUCTIVE PHENOLOGY:
Germination and leafing dates are unknown. Budding and Anthesis
occur in April to May (02,08). Fruiting occurs in mid-summer and
seed/fruit dispersal dates are unknown (02,08).
SEX OR SPORE STATUS:
Monoclinous (03,04,05,06,07). Some individuals are partially
male-sterile (few pollen grains, as compared to normal Echinocereus
flowers) (08). This is consistent with the hypothesis of a hybrid
origin of this species (08).
POLLINATION, SPORE AND SEED DISSEMINATION:
Pollen dissemination agents are insects (02). The seed
dissemination agents are probably vertebrates (08). Seedlings are not
concentrated close to the parent plants; presumably the ripe fruits
are removed and consumed by vertebrates, so that the seeds do not fall
close to the female plant (08).
SEED BIOLOGY:
Seeds germinate easily and rapidly in cultivation (02). The seed
biology in nature is unknown.
POPULATION BIOLOGY:
According to Weniger (02), the population in Pecos County has
declined drastically over the last 15 years. Here the population is
composed of various sized individuals, but small seedlings were not
observed (02). The cacti were numerous, with an individual every
hundred feet, but most were destroyed by the highway or taken by
collectors (02). A few miles east of the type locality, Zimmerman saw
several dozen plants in six hours of searching; small seedlings were
few and inconspicuous (08).
The status of the other populations is unknown, but most of the
individuals collected have been old adults (08). The plants 23 to 26
miles south of Fort Stockton are sparse; the 6 plants seen there thus
far were all adults (08).
In Pecos County, the complete range of intermediates between E.
lloydii and the much-more-common E. dasyacanthus suggests
introgression, which might eventually result in dilution (swamping) of
the E. lloydii genepool (08).
ECOLOGICAL/EDAPHIC FACTORS:
E. lloydii grows on sandy, gravelly, or rock soils on slopes and
Life History - 1 (DRAFT) - Life History
Species CACTUS, HEDGEHOG, LLOYD'S
Species Id ESIS702015
Date 13 MAR 96
hillsides, as well as on bare rock ledges (02,03), and on fine
textured alluvial valley floors (08). The rock or gravel is usually
limestone, occasionally with weathered metamorphic rock. The climate
is hot (64 to 68 degrees F mean annual temperature) and arid (8 to 14
inches mean annual precipitation) (11). The elevation varies between
900 and 1650 meters (03). Usually E. lloydii grows on open, fully
exposed sites with scattered forbs, grasses, and brush (02), although
sometimes it occurs in dense mesquite scrub among tall grasses (08).
Apparent nurse-plants (shrubs and perennial grasses) commonly are
associated with E. lloydii plants; a definite requirement for nurse-
plants is documented for seedlings of E. triglochidiatus var.
gonacanthus, which has a similar growth-habit to E. lloydii, elsewhere
in the Chihuahuan Desert (13).
In Texas, geologic formations in the area of E. lloydii in
Culberson County are the Brushy Canyon formation (mostly sandstone;
Permian), and old and young Quaternary deposits (15). The soils in
the area of occurrence of this species in Culberson County are not
mapped (19). In Pecos County, the area of occurrence includes
Holocene alluvium and fan deposits, Quaterary deposits, the Perdiz
Conglomerate and similar gravel deposits (Quaternary and Tertiary),
the Tessey and Capitan limestones (both Permian), and the Washita and
Fredericksburg groups (limestone, dolomite, chert, and marl; lower
Cretaceous) (15). E. lloydii occurs on aridisols and mollisols in
Pecos County (16). The soil associations and series in this area are
Ector, Ector-Rock Outcrop, Hodgins, Iraan, Lozier, Reagan, Sanderson,
and Upton (16). In the vicinity of the Presidio County locality are
young and old Quaternary deposits and Bolson deposits (clay, silt,
sandstone, and conglomerates; Pleistocene to Miocene) (15). The soil
orders are aridisols, entisols, and mollisols; and the soil
associations are Glendale-Anthony-Toyah and Nickel-Canutio (18).
In New Mexico, geologic formations in the area of E. lloydii in
Dona Ana County are the Camp Rice and Sierra Ladrones formations
(Quaternary), and the following Cretaceous formations: Sarten,
Beartooth Sandstone, Anapra, Mesilla Valley, Muleros, and Smeltertown
(17). Also in Dona Ana County, E. lloydii occurs on the Nickel-Upton
association, Rock outcrop-Argids association, and Tencee-Upton
association (20). In Eddy County, near Carlsbad, the formations are
Quaternary alluvium, dunes, terraces, and pediments (17). The Sitting
Bull Falls locality is on Permian limestone. In New Mexico in
general, E. lloydii occurs on aridisols, entisols, and mollisols (20).
The rather general locality of "near Carlsbad" includes numerous soil
series: Atoka, Anthony, Arno, Dev, Ector, Cottonwood, Gypsum-land,
Harkey, Karro, Kermit, Berino, Duneland, Pajarito, Pima, Reagan,
Bippus, Simona, Tonuco, and Upton (20). In the Sitting Bull Falls
area, the following soil complexes occur: Deama-Rock outcrop, Rock
outcrop-Deama complex, and Rock outcrop-Tortugas-Ustiluvents complex
(20). In Otero County, geologic formations in the area of E. lloydii
are Pennsylvanian (the Magdalena Group) and Permian (Yeso and Abo-
Hueco Formations) limestones with Tertiary intermediate to silicic
intrusions (17). Also, in Otero County, the cactus is found on the
Nickel-Tencee association and Rock outcrop (20). The very general
locality of "30 miles west of Artesia" falls within Chaves County for
which geologic associations include formations that are Quaternary
Life History - 2 (DRAFT) - Life History
Species CACTUS, HEDGEHOG, LLOYD'S
Species Id ESIS702015
Date 13 MAR 96
alluvium, dunes, terraces, and pediments (17). In Chaves County, the
soils in the area of occurrence are Ector-Rock complex, Lozier-Tencee
complex, Pecos-Dev association, Reakor-Pecos association, and the
Tencee cobbly loam (20).
TROPHIC STATUS:
Phototrophic (03,04,05,06,07).
CHARACTERISTIC DOMINANCE:
Component (08).
COMMUNITY ECOLOGY:
Echinocereus lloydii is a component of the Chihuahuan Desert,
xeromorphic shrub, a stable community (14).
In Pecos County, the complete range of intermediates between E.
lloydii and the much-more-common E. dasyacanthus suggests
introgression, which might eventually result in dilution (swamping) of
the E. lloydii gene-pool (08).
SPECIES INTERRELATIONSHIPS:
Apparent nurse-plants (shrubs and perennial grasses) commonly are
associated with E. lloydii plants; a definite requirement for nurse-
plants is documented for seedlings of E. triglochidiatus var.
gonacanthus, which has a similar growth-habit to E. lloydii, elsewhere
in the Chihuahuan Desert (13).
OTHER LIFE HISTORY DESCRIPTORS:
At least in Pecos County, Texas, the purity of the lloydii gene-
pool may be threatened by introgression from E. dasyacanthus, a much
commoner and more widespread species (08). The apparent ease of
hybridization between these species is consistent with the hypothesis
that E. lloydii originated through former hybridization between the
ancestors of E. dasyacanthus and E. troglochidiatus, which are
sympatric with each other in many parts of west Texas and southern
New Mexico (08).
In the Jarilla Mountains, Otero County, New Mexico, the
population identified as lloydii consists of (or is involved in) an
apparent hybrid swarm involving at least three species of Echinocereus
(E. dasyacanthus, E. troglochidiatus var. neomexicanus, and E.
viridiflorus) that normally are sympatric without hybridization (08).
These species are very different in appearance, and display
pollination syndromes adapted for large bees, hummingbirds, and small
bees, respectively (08). The hybrids involving E. viridiflorus are
sterile or nearly so, consistent with the different ploidy level of
that species; E. viridiflorus is a diploid, while E. lloydii, E.
troglochidiatus var. neomexicanus, and E. dasyacanthus all are
tetraploid (08).
Life History - 3 (DRAFT) - Management Practices
Species CACTUS, HEDGEHOG, LLOYD'S
Species Id ESIS702015
Date 13 MAR 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial Restricting Poaching
Beneficial Controlling/Restricting Noncommercial Harvest
Beneficial Regulating commercial harvest levels
Adverse Collecting
Existing Collecting
Adverse Commercial Exploitation
Existing Commercial Exploitation
Adverse Gas/Oil Development
Existing Gas/Oil Development
Adverse Highway/Railroads
Existing Highway/Railroads
Adverse Soil compaction by heavy equipment in mine areas
Existing Soil compaction by heavy equipment in mine areas
COMMENTS ON MANAGEMENT PRACTICES -
Part of the Echinocereus lloydii population in Pecos County, TX,
was destroyed by the construction of Interstate Highway 10 (02).
Highway and roadside maintenance threatens any individuals in the
immediate vicinity. In this same general area, some plants are in a
producing oil field which, so far, has had minimal effects on the
species (02). By far the most serious threat comes from private and
commercial collecting of the greatly prized and beautiful, rare
collector's item (02).
Future threats might be brush control management techniques, such
as clearing or herbicides, and farming (a large area of scrub is
visible from IH 10, not far east of Tunas Springs, has been cleared
and might be a vineyard; more such developments might be forthcoming)
(08).
UNAPPROVED PLAN:
No target date for the initiation of a Recovery Plan has been
established as of 1986.
There is an ongoing study to determine whether Echinocereus
lloydii is actually a distinct taxon. Until this is determined, a
Recovery Plan will not be undertaken. In the interim it is
recommended that the species be managed through enforcement of
existing collecting and trade regulations, and protection of habitat
from Federal actions contiune through Section 7 of the Endangered
Species Act.
Management Practices - 1 (DRAFT) - References
Species CACTUS, HEDGEHOG, LLOYD'S
Species Id ESIS702015
Date 13 MAR 96
References
References - 1 (DRAFT) - References
Species CACTUS, HEDGEHOG, LLOYD'S
Species Id ESIS702015
Date 13 MAR 96
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 Warnock, B.H. 1974. Wildflowers of the Guadalupe Mountains and
Sand Dune Country, Texas. Sul Ross State Univ., Alpine.
02 Weniger, D. 1979. Status report on Echinocereus lloydii. On file
at: U.S. Fish and Wildlife Service.
03 Benson, L. 1982. The cacti of the United States and Canada.
Stanford Univ. Press, Stanford.
04 Weniger, D. 1970. Cacti of the southwest. Univ. of TX Press,
Austin.
05 Benson, L. 1969. Cactaceae in flora of Texas, Vol. II. Texas
Research Found., Renner.
06 Correll, D.S. and M.C. Johnston. 1970. Manual of the vascular
plants of Texas. Texas Research Foundation, Renner.
07 Britton, N.L. and J.N. Rose. 1963. The Cactaceae, Vol. III.
Dover Public., Inc., NY.
08 Zimmerman, A.D. 1984. Pers. comm. Department of Biology,
University of Texas, Austin, TX 78712.
09 Knight, P. 1984. Pers. comm. Department of Natural Resources,
Villagra Building, Santa Fe, NM 87503.
10 Leuk, E.E., II. 1980. Biosystematic studies in the Echinocereus
viridiflorus complex. Ph.D. dissertation. Univ. of OK, Norman.
11 Godfrey, C.L., G.S. McKee and H. Oakes. 1973. General soil map of
Texas. TX Agri. Exp. Sta., Texas A and M Univ., College Station.
12 Department of Interoir. 1979. Environmental Assessment.
13 Lozano, R. and W. Reid. 1982. Claret cup cactus at White Sands
National Monument. Cact. and Succ. J. (US) 54:196-201.
14 Diamond, D.D. 1984. Pers. comm.
15 Bureau of Economic Geology. 1965-1983. Geologic atlas of Texas.
Univ. of Texas, Austin.
16 Rives, J.L. 1980. Soil survey of Pecos County, Texas. USDA.
17 Mew Mexico Geological Society. 1982. New Mexico Highway Geologic
Map.
18 Soil Conservation Service. 1973. General soil map, Presidio
County, Texas.
19 Rives, J.L. 1985. Pers. comm.
20 Ruiz, J.E. 1985. Pers. comm.
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
01 Zimmerman, A.D. 1984. Pers. comm. Department of Biology,
University of Texas, Austin, TX 78712.
02 Knight, P. 1984. Pers. comm. Department of Natural Resources,
Villagra Building, Santa Fe, NM 87503.
03 Benson, L. 1982. The cacti of the United States and Canada.
Stanford Univ. Press, Stanford.
04 Weniger, D. 1970. Cacti of the southwest. Univ. of TX Press,
Austin.
05 Warnock, B.H. 1974. Wildflowers of the Guadalupe Mountains and
Sand Dune Country, Texas. Sul Ross State Univ., Alpine.
References - 2