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Vascular Plants With Water-Conducting Cells (Xylem Tissue): Gymnosperms, Angiosperms & Ferns

      Floristic Subgroup      
  San Diego County  
  State Of California  
# of Native Species
1573 (73.4%)
4976 (83.4%)
# of Naturalized Species
570 (26.6%)
991 (16.6%)
Total # of Species
Total # of Taxa Including
Subspecies & Varieties
# of Endemics
1315 (22%)
# of Families
# of Pines (Pinus) *
18 (7 ssp. & 3 var.)
# of Cypress (Hesperocyparis) **
10 (2 var.)
# of Locoweeds (Astragalus) ***
20 (8 var.)
97 (71 var.)

* 94 species of Pinus in the N. Hemisphere     ** 14 species of Hesperocyparis in N. America
*** 389 spp. of Astragalus in N. America & 2500 spp. worldwide; 23 var. of A. lentiginosus in CA!

Astragalus: The Largest Genus Of Flowering Plants
Astragalus in Carrizo Plain Of San Luis Obispo County
Astragalus oxyphysus & Dead Steer In Kern County, CA
  Asteraceae: World's Largest Family of Of Flowering Plants  

The state of Hawaii (Hawaiian Archipelago) has 152 plant families and 2,089 native & naturalized species. Approximately 1100 species are native and 90 percent of these are endemic to the archipelago. The volcanic islands are about 70 million years old and the original 299 successful colonists got here by wind, wing and water (air currents, birds & ocean currents). By comparison, Florida has 4,275 species, 1195 of which are naturalized. Florida and Hawaii have many naturalized species that are cultivated ornamentals, but not naturalized, in California.

Vascular Plant Families & Page Numbers In Jepson Manual 2nd Edition
Balsaminaceae & Zingiberaceae are waifs: Garden escapes that are not truly naturalized.

  Vector File Of Alphabetical Family List To Tape Into Jepson Manual 2nd Ed.  

On-Line Links For Jepson Manual

   List Of Plant Families  
   A Key To The Genera  
   A Key To Plant Families  
   Glossary Of Plant Terms   
   Geographic Subdivisions  

Native Versus Naturalized Plants In California

Native: A species component of the original flora and fauna of a region. Native is synonymous with the term indigenous. The specific region may be defined as a state (such as California), or a larger geographic region, such as Old World or New World. Generally, true native species were present in a particular region long before political boundaries were established, and they were not introduced by people.

Plants that are restricted to one or more specific localities within a region are termed endemic. For example, the Torrey pine is native as well as endemic to California. Although commonly cultivated, it only grows wild on the sandstone bluffs between Del Mar and La Jolla in San Diego County, and on Santa Rosa Island. Because of the many isolated mountain ranges and valleys in California, approximately 22 percent of the flora is endemic to the state. Some endemic plants in California include the California cypresses (Hesperocyparis), Santa Cruz Island ironwood (Lyonothamnus floribundus ssp. asplenifolius), Death valley sage (Salvia funerea), Death Valley locoweed (Astragalus funereus), Panamint daisy (Enceliopsis covillei), and Death Valley gilmania (Gilmania luteola). Death Valley is especially rich in endemics because of its isolation from other regions. It is surrounded by high mountain ranges and hundreds of miles of arid desert. In fact, one of the rarest endemic wildflowers in California is called "rock lady" (Maurandya petrophila syn. Holmgrenanthe petrophila), a member of the plantain family (Plantaginaceae). This unusual plant grows in crevices on vertical limestone walls in steep canyons of the Grapevine Mountains bordering Death Valley.

Naturalized: True naturalized plant species are introduced from another region (outside California). Because they are able to grow wild and reseed themselves, they are considered part of the California flora. Some naturalized species are considered very destructive to the natural environment because they are extremely invasive and may replace the native species. This is especially serious when the loss of native plants threatens the survival of native animals that depend on the plants for food. Naturalized plants that are considered undesirable are often referred to as weeds. It has been estimated that more than 16 percent of the California flora is composed of naturalized species. Naturalized "weeds" often have ingenious methods of dispersal, including hitchhiking on animals and airborne seeds. A single tumbleweed plant (Salsola tragus) may produce 20,000 to 50,000 seeds within numerous small fruits, each surrounded by a circular, papery border. Mature plants readily break off at the ground level and are pushed along by strong gusts of wind. As they roll along hillsides and valleys, the seeds are scattered across the landscape. The introduction of Saharan mustard (Brassica tournefortii) into the Anza-Borrego desert region is an ecological disaster. The South African shrub called boneseed (Chysanthemoides monilifera ssp. monilifera) was introduced into the Palomar College Arboretum in the 1970s and has become locally naturalized. It is listed for California in the Flora of North America but not in the Jepson Manual.

Boneseed (Chysanthemoides monilifera ssp. monilifera) on Owens Peak north of Palomar College.

Sahara Mustard In Anza-Borrego Desert
  Ecology Definitions: Native Vs. Naturalized  

Is The Pink-Flowered Arizona Devil's Claw Native or Naturalized In California?

The pink-flowered annual (Proboscidea parviflora ssp. parviflora) is common along the Gila River flood plain where it grows wild on the banks, along fences and in abandoned fields where there is plenty of moisture. P. parviflora ssp. parviflora was probably introduced into California because its few known locations are near abandoned Native American settlements. According to unabridged note in the on-line Jepson Manual 2nd Edition (2012), all California material previously identified as P. parviflora ssp. parviflora belongs instead to P. parviflora var. hohokamiana. It has been collected from several isolated desert areas of Inyo County, including Johnson Canyon west of Death Valley, near the mouth of Hunter Canyon in remote Saline Valley and near historic Fort Independence in Owens Valley. Although I could only find a few dried seed capsules with black seeds when I visited these sites during the 1980s, some of the pods from Saline Valley appeared to be the white-seeded var. hohokamiana. See following link for more information & images.

Peter Bretting of Indiana University (Amer. Jour. Botany Vol. 69, 1982) has named two varieties of the pink-flowered devil's claw, a wild black-seeded type (P. parviflora ssp. parviflora var. parviflora) and a domesticated white-seeded race (P. parviflora ssp. parviflora var. hohokamiana). The white-seeded cultivar (var. hohokamiana) has been cultivated for generations on several Native American rancherias in Arizona for its superior basket-making qualities. Known as 'ihug (pronounced EE-hook), the striking seed capsules may have claws up to 15 inches (38 cm) long. Multiclawed forms of both varieties were also selected because the horns split into 3-4 claws. Like the famous rugs and blankets of the Navajo, baskets of the Papago are well-known for their durability, beauty and intricate designs. The four basic colors in the baskets are white, black, green and red. White is from sun-bleached dried yucca leaves (often from Yucca elata), while green is from unbleached dried yucca leaves. A red dye obtained from yucca roots is sometimes used to color the leaves. Narrow strips of yucca leaves are tightly wound around slender, fibrous bundles of beargrass leaves (often from Nolina microcarpa) producing the unique coils of the baskets. If you look closely between the coils of yucca leaves you can see the bundles of beargrass leaves.

  Devil's Claws: Hitchhikers On Big Animals  

Seed cones from cypress groves in California, Arizona and outside the U.S.

A - N: New World Cypress (Hesperocyparis)
formerly placed in the genus Cupressus
O - R: Old World Cypress (Cupressus)
Includes the Italian Cypress
S: False Cypress (Chamaecyparis)
Includes the Port Orford Cedar
T - U: Nootka Cypress (Callitropsis) Includes
Alaska Cedar; may become Xanthocyparis

A. Tecate cypress (Hesperocyparis forbesii), B. Sargent cypress (H. sargentii), C. Piute cypress (H. nevadensis), D. Cuyamaca cypress (H. stephensonii), E. Santa Cruz cypress (H. abramsiana, F. Monterey cypress (H. macrocarpa), G. Gowen cypress (H. goveniana), H. Mendocino cypress (H. pygmaea), I. Macnab cypress (H. macnabiana), J. Modoc cypress (H. bakeri), K. Smooth-bark Arizona cypress (H. glabra), L. Rough-bark Arizona cypress (H. arizonica), M. San Pedro Martir cypress (H. montana), N. Mexican cypress (H. lusitanica), O. Italian cypress (Cupressus. sempervirens), P. Sahara cypress (C. dupreziana), Q. Kashmir cypress (C. cashmeriana), R. Mourning cypress (C. funebris), S. Port Orford cedar (Chamaecyparis lawsoniana), T. Alaska cedar (Callitropsis nootkatensis), U. Leyland cypress Callitropsis x leylandii).

Cupressus: Remarkable Conifers Native To California
  Arboretum Conifers: The Cypress Family (Cupressaceae)  

The Angiosperm Phylogeny Group (APG) has proposed some significant changes in the classification of many traditional angiosperm families, including the placement of all duckweeds in the Araceae rather than the Lemnaceae. Nomenclatural changes are cited under the APG II system (2003) and superceeded by APG III system (2009). These changes are based on computer-generated evolutionary trees or cladograms. Thousands of data characters have been used, including morphology, anatomy, flavonoids, allozymes, and DNA sequences from chloroplast genes and introns. The Jepson Manual Second Edition essentially follows the changes summarized in the following reference by W.T. Judd, et al. 2008. The incorporation of these changes into textbooks, floras, checklists and herbarium collections is a formidable task, not to mention relearning hundreds of new names.

  Judd, W.S., Campbell, C.S., Kellogg, E.A., Stevens, P.F., and M.J. Donaghue. 2008. Plant Systematics: A Phylogenetic Approach (Third Edition). Sinauer Associates, Inc., Sunderland, Massachusetts. 611 p.

  Angiosperm Phylogeny Group (2003). "An Update of the Angiosperm Phylogeny Group Classification for the Orders and Families of Flowering Plants: APG II." Botanical Journal of the Linnean Society 141 (4): 399-436.

  Angiosperm Phylogeny Group (2009). "An Update of the Angiosperm Phylogeny Group Classification for the Orders and Families of Flowering Plants: APG III." Botanical Journal of the Linnean Society 161 (2): 105-121.

  DNA Polymerase & Phylogenetic Trees  

New Jepson Manual: Some Major Taxonomic Changes

1. Monophyletic Groupings: All Descendants From A Common Ancestor

Duckweeds Placed In Arum Family (Araceae) & Genus Acacia Split

  Cladogram For The Arum Family Based On Chloroplast DNA  
Flow Chart For Duckweed Family Based On Morphologhy

Controversies Over The Genus Landoltia

Many traditional phylogenetic groupings of species within families and genera are not monophyletic and are inconsistent with modern cladistical analyses based on DNA. In other words, the groupings are paraphyletic or polyphyletic, and do not show all species within a group descending from a common ancestor. Monophyly is the natural evolutionary pattern in which all species are descended from a common ancestor. In order to have consistent computer-generated, monophyletic cladograms, it is sometimes necessary to change paraphyletic and polyphyletic groupings by moving species into different genera, and by moving genera into different families. Many of the taxonomic revisions in the Jepson Manual 2nd Edition (2012) were made in order to have consistent monophyletic groupings. This is why Spirodela punctata was placed in the genus Landoltia and why the Lemnaceae was placed in the familiy Araceae.

The cladogram (left) is from D.H. Les and D.J. Crawford (1999). It has high boot strap values and is based on molecular (rbcL) data from chloroplast DNA. It clearly shows that a grouping composed of 3 species of Spirodela is paraphyletic. This is why S. punctata was placed in the monotypic genus Landoltia.

  Monophyletic Groupings: All Descendants From A Common Ancestor  

In 1999, D.H. Les and D.J. Crawford proposed the new genus Landoltia containing one species L. punctata, formerly Spirodela punctata. This species is morphologically intermediate between Lemna and Spirodela. According to Les & Crawford, it represents an isolated clade distinct from both Lemna and Spirodela. Without this change, the genus Spirodela would be paraphyletc.

  • Les, D.H., and D.J. Crawford. "Landoltia (Lemnaceae), A New Genus of Duckweeds." Novon 9: 530-533.

Spirodela intermedia
Spirodela polyrrhiza
Landoltia punctata
Formerly Spirodela punctata
All Species
Prophyllum At Base Of Frond
Present But Reduced
Number of Roots
Penetrating Prophyllum
S. intermedia: 2 to 5
S. polyrrhiza: 1 (rarely 2)
All Roots
No Prophyllum
Overwintering Turions
S. intermedia: None
S. polyrrhiza: Present
None Distinct; Some Small
Fronds Resemble Turions
Present in
L. turionifera
No. of Veins In Frond
7 to 16
3 to 7
1 to 5
No. of Roots
7 to 21
Typically 2 to 5
Only 1
Root Tracheids
Extend to Tip
Basal Only
Dorsal Meristem of New Fronds
On One Side
(Lateral on other side.)
On Both Sides
On Both Sides
External Anther Locules
Do Not Extend Above
Internal Locules
Extend Slightly Above
Internal Locules
Extend Above The
Internal Locules
Brown Pigment Cells In Fronds
Cells With Crystals
Raphides & Druses
Raphides & Druses
Raphides Only

A comparison of morphological features between Landoltia, Spirodela and Lemna. With so few taxonomic characteristics, these assume a more important role in distinguishing genera. Spirodela punctata has a taxonomic position intermediate between Spirodela (S. intermedia & S. polyrrhiza) and Lemna. A hypothetical cladogram in Les and Crawford (1999) based on morphological data from Landolt (1986) revealed a paraphyletic grouping of Spirodela before Spirodela punctata was finally placed in the monotypic genus Landoltia.

According to Professor Dr. Elias Landolt (personal communication, 2001), the creation of the new genus Landoltia is not necessary based on a purely morphological point of view; however, based on DNA and enzymatic studies, the change is warranted in order to form phylogenetically consistent taxa. The inclusion of a fifth genus Landoltia appears to be necessary based upon a comprehensive analysis of the Lemnaceae by D.H. Les, D.J. Crawford, E. Landolt, J.D. Gabel, and R.T. Kimball (2002). More that 4,700 characters were studied, including data from morphology and anatomy, flavonoids, allozymes, and DNA sequences from chloroplast genes (rbcL, matK) and introns (trnK, rpl16).

The Angiosperm Phylogeny Group (APG) has proposed some significant changes in the classification of many traditional angiosperm families, including the placement of all duckweeds in the Araceae rather than the Lemnaceae. Nomenclatural changes are cited under the APG II system (2003) and superceeded by APG III system (2009). These changes are based on computer-generated evolutionary trees or cladograms. Thousands of data characters have been used, including morphology, anatomy, flavonoids, allozymes, and DNA sequences from chloroplast genes and introns. The Jepson Manual Second Edition (2012) essentially follows the changes summarized in the following reference by W.T. Judd, et al. 2008. Since the genus Landoltia was proposed by D.H. Les and D.J. Cawford in 1999, several classic papers on the phylogeny of the duckweed subfamily (Lemnoideae) and other aroids (Araceae) have used the name Landoltia. In my opinion, the name Landoltia is warranted because it is consistent with the objectives of the Jepson Manual 2nd Edition (2012) based on phylogenetic studies using plastid DNA.

  • Judd, W.S., Campbell, C.S., Kellogg, E.A., Stevens, P.F., and M.J. Donaghue. 2008. Plant Systematics: A Phylogenetic Approach (Third Edition). Sinauer Associates, Inc., Sunderland, Massachusetts. 611 p.

  • Les, D.H., D.J. Crawford, E. Landolt, J.D. Gabel, and R.T. Kimball. 2002. "Phylogeny and Systematics of Lemnaceae, the Duckweed Family." Systematic Botany 27 (2): 221-240.

  • Cabrera, L.I., Salazar, G.A., Chase, M.W., Mayo, S.J., Bogner, J., and P. Davilá. 2008. "Phylogenetic Relationships of Aroids and Duckweeds (Araceae) Inferred From Coding and Noncoding Plastid DNA." American Journal of Botany 95 (9): 1153-1165.
See Images Of Landoltia punctata (syn. Spirodela punctata)
  Cladogram For The Arum Family Based On Chloroplast DNA  

An argument for replacing the names Landoltia punctata and Spirodela punctata with the previous name Spirodela oligorrhiza has been made by Daniel B. Ward (2011). In order to make sure we are referring to the same species, Ward has suggested calling this "Lesser Greater Duckweed" to avoid confusing it with the larger species of Spirodela (S. polyrrhiza & S. intermedia) called "Greater Duckweeds." In this article I will simply call it LG Duckweed instead of Lesser Greater Duckweed.

  • Ward, D.B. 2011. "Spirodela oligorrhiza (Lemnaceae) is the Correct Name for the Lesser Greater Duckweed." J. Bot. Res. Inst. Texas 5 (1): 197-203.

Spirodela punctata (Meyer) Thompson was named by C.H. Thompson in 1898 based on a collection from the 1938-1842 Wilkes Expedition, labeled Orange Harbor, Tierra del Fuego. Whether this collection actually came from the tip of South America is debatable. The parenthetical author G.F.W. Meyer described this species earlier as Lemna punctata from a type specimen collected in Guyana, South America in 1818. Unfortunately, Meyer's original type specimen was lost. According to Ward (2011), LG Duckweed does not occur in the areas where these collections were made: The Tierra del Fuego collection was mislabeled and the Guyana collection was not LG Duckweed! Futhermore, he states that the only native Spirodela in South America is S. intermedia. Since Meyer's type speciment was lost, Ward neotypified the species as Lemna punctata G.F.W. Meyer. Thompson's binomial is still Spirodela punctata (Meyer) Thompson; however, this no longer refers to LG Duckweed. It is now the correct binomial for the South American Spirodela intermedia. The correct name for LG Duckweed now becomes Spirodela oligorrhiza (Kurz) Hegelmaier, a name published by Hegelmeier in 1868. Hegelmeier apparently never saw the South American specimens discussed above, so his name is probably based on the true LG Duckweed.

Ward's 2011 neotypification will make Landoltia a synonym of Spirodela and no longer available for the intended LG Duckweed. The restoration of separate generic status for LG Duckweed now known as Spirodela oligorrhiza (Kurz) Hegelm. will require the creation of a new genus name. The binomial Spirodela punctata (Meyer) Thompson will now refer to the South American species known as Spirodela intermedia W. Koch. By neotypification the name Landoltia also becomes correctly applied to Spirodela intermedia.

According to E. Landolt (Personal Communication, 2012), the name change proposed by Ward in untenable:

  • "I think this problem cannot be solved definitely. The main problem is the fact that it is not possible to decide which species Meyer was describing under the name of Lemna punctata. Certainly, it has to be a species of the genus Spirodela sensu lato because we don't know any other species within the Lemnoideae with pigment cells ("punctata"). The description of Meyer is very rudimentary. I could not find any herbarium specimen collected by Meyer. His description could concern Spirodela oligorrhiza, Spirodela intermedia or Spirodela polyrrhiza. I collected all of these species in northern South America. The description fits best for Spirodela oligorrhiza because it mentions 2-to 3 roots per frond. Most individuals of S. oligorrhiza in nature have 2 to 5 roots. S. polyrrhiza and S. intermedia mostly have more than 8 roots (up to 18). Only very rarely and only in very young fronds they show less then 5 roots. L. punctata was collected by Meyer in Guyana. On the other side, S. intermedia is known from the neighbouring state Surinam and surely is indigenous in the region. S. polyrrhiza and S. punctata might be introduced to South America. Today, S. punctata is frequent in the regions of Rio and Sao Paulo, in Venezuela, Colombia and Ecuador. I have collected S. polyrrhiza in Colombia and Ecuador. Even if S. punctata is introduced into South America it is not known at which year the introduction took place for the first time. It looks like S. punctata would be easily distributed by ship from harbour to harbour and from there by bird to places within a continent."

    "I can understand that Thompson choose a new type for Lemna punctata. The correctness of his decision is not disputed. I checked the neotype the collection of Wilkes from copies in four different Herbara. It is clearly the species which is now called "punctata". It is not important if the material was collected in Orange Harbor or somewhere else. Because it is not possible and will probably never be possible to decide the identity of Lemna punctata with certainity it is not advisable to change the correctly published neotype of Thompson. If we change the type of L. punctata again we will have a terrible chaos in nomenclature. Therefore I am not following the proposal of Ward."

A. Landoltia punctata (Spirodela punctata = S. oligorrhiza); B. Lemna minuta. The upper surface of Landoltia punctata is clearly punctate (appearing pitted). In dead fronds these punctae show up as brown pigment cells composed of oxidized & polymerized quinones similar to brown, oxidized phenolic componds in sliced apples and potatoes. Duckweeds with 2-3 (5) roots and a punctate dorsal surface are undoubtedly Landoltia punctata. The punctate surface is undoubtedly why G.F.W. Meyer originally named this species Lemna punctata nearly 200 years ago.

Dorsal view of dried herbarium specimen of Landoltia punctata showing brown pigment cells (punctae) in subepidermal layer of plant body (frond). The image was taken through an Olympus compond microscope with a Sony W-300 digital camera. Pigment cells occur in the plant bodies of other species of Spirodela. They are also in some species of Wolffia and Wolffiella, but not in Lemna. In fact, the punctate species Wolffia brasiliensis (formerly W. punctata) was originally named after these pigment cells or punctae. Wolffia punctata has also been used for W. borealis, but the correct synonym is W. brasiliensis. Magnification 100x and 400x.

My objection to Ward's proposed neotypification is based on two primary points. (1) He is neotypifying Meyer's lost type specimen with Spirodela intermedia. It is impossible to know with 100% certainty which species Meyer was describing under the name Lemna punctata back in 1818. It could have been the "LG Duckweed" that we know as Landoltia punctata (Spirodela punctata = Spirodela oligorrhiza), or it could have been another species of Spirodela such as S. intermedia. Why complicate this taxonomy based on speculation. (2) Cladistical analysis has clearly shown that Spirodela punctata belongs in a separate genus (Landoltia), otherwise the grouping of Spirodela with 3 species is paraphyletic. The trend in modern floras such as the Jepson Manual Second Edition (2012) is for consistent monophyletic groupings.

  See Another Taxonomic Controversy Regarding Incorrect Type Specimens  

Based on derived characteristics over time, modern phylogenetic trees (cladograms) of animal and plant groupings show all taxa descending from a common ancestor. This grouping is termed monophyletic. Starting with a common ancestor all the branching is in 2's (dichotomous), with every new branch (clade) giving rise to a pair of closely related sister clades. Each of these clades in turn gives rise to another pair of sister clades, and so on. Evolutionary relationships displayed in cladograms are not always dichotomous. Three or more branches may arise from a node (polytomy) when closely-related taxa cannot be completely resolved into dichotomies. This is clearly seen in the cladogram for Acacia (see below). In monophyletic groupings all descendants have a common ancestor and share one or more derived characters. See the following simplified cladogram.

A modern representation of the phylogeny of gymnosperms based on chloroplast DNA. Dichotomous (paired) sister branches (clades) with a common ancestor are said to be monophyletic and are more closely related. For example, the conifer division Pinophyta and ginkgo division (Ginkgophyta) have a common ancestor in the cycad division (Cycadophyta). The pine family (Pinaceae) and a sister branch leading to six additional families have a common ancestor within the division Pinophyta. In other words, the seven major families of cone-bearing trees and shrubs all evolved from the division Pinophyta. The araucaria and podocarpus families (Araucariaceae and Podocarpaceae), which have their greatest diversity in the southern hemisphere, are monophyletic and occur side-by-side on sister clades.

Many traditional phylogenetic groupings of species within families and genera are not monophyletic and are inconsistent with modern cladistical analyses based on DNA. In other words, the groupings are paraphyletic or polyphyletic, and do not show all species within a group descending from a common ancestor. Monophyly is the natural evolutionary pattern in which all species are descended from a common ancestor. In order to have consistent computer-generated, monophyletic cladograms, it is sometimes necessary to change paraphyletic and polyphyletic groupings by moving species into different genera, and by moving genera into different families. Many of the taxonomic revisions in the Jepson Manual 2nd Edition (2012) make more sense if you understand the terms monophyletic, paraphyletic and polyphyletic. For example, why was the duckweed family (Lemnaceae) reduced to a subfamily (Lemnoideae) within the arum family (Araceae)? Why were non-phyllode acacias with prickles (e.g. cat's claw acacia) removed from the genus Acacia and placed in a separate genus Senegalia? Hopefully, the following chart will shed some light on these significant changes.

Maintaining the duckweeds (Lemnaceae) and arums (Araceae) as distinct families would make the arum family paraphyletic, with a common ancestor but without all of its descendants (i.e. duckweeds are excluded). In order to have a monophyletic, computer-generated cladogram, the duckweeds are now placed in the family Araceae. Modern reptiles is also a paraphyletic grouping that contains a common ancestor, but does not contain all descendants (i.e. birds are excluded).

Morphological and genetic studies have shown that the genus Acacia is polyphyletic. As shown in the simplified diagram above, the most recent ancestor of "C" is not part of the grouping within the blue square. For example, it has derived traits that are not shared by the common ancestor. Therefore, it cannot be part of the group with A & B. In order to maintain Acacia as a monophyletic genus, "C" must be placed in a different clade. If "C" and "D" share the same derived traits and common ancestor, then "C" must be a sister clade with "D." This is essentially why some previous members of the genus Acacia, such as the "cats claw acacia" (Acacia greggii) are now placed in the genus Senegalia. A grouping of warm-blooded animals would include birds and mammals and is called polyphyletic because the members of this group do not include the most recent common ancestor.

Cat's Claw Acacia Now In Genus Senegalia

Most members of the genus Senegalia differ from Acacia by the presence of prickles and the absence of phyllodes. A naturalized acacia in San Diego County called "sweet acacia" (A. farnesiana var. farnesiana) has been placed in the genus Vachellia. Members of the genus Senegalia can be distinguished from Vachellia by the absence of stipular spines and the presence of prickles. The origin of stipular spines vs. prickles is quite different, and molecular taxonomists have concluded that the separation of these species into separate groups is warranted.

 Seigler, D.S., Ebinger, J.E., and J.T. Miller. 2006. "The Genus Sengalia (Fabaceae: Mimosoideae) Phytologia 88 (1): 38-94.

 Maslin, B.R., Miller, J.T., and D.S. Seigler. 2003. "Overview of the Generic Status of Acacia (Leguminosae: Mimosoideae)." Australian Systematic Botany 16 (1): 1-18.

A. Prickles of cat's claw acacia (Senegalia greggii). B. Stipular spines of sweet acacia (Vachellia farnesiana var. farnesiana). Unlike stipular spines at the bases of leaves, prickles arise from the cortex and epidermis of plant stems. The classic thorns of roses are actually prickles.
This simplified dichotomous flow chart is not a computer-generated, monophyletic cladogram. It simply shows how the traditional genus Acacia was subdivided into groups in order to key out different species. Some of these species with prickles and stipular spines have been removed from the genus Acacia and placed in new genera. The original 1350 species now comprise 5 genera, with 960 (mostly Australian) spp. still retained in Acacia.

  See Wayne's Word Article On The Genus Acacia  
Swollen Thorn Acacias & Their Symbiotic Ants
Vegetative Terms: Spines, Thorns & Prickles

Simplified, computer-generated cladogram of Acacia sensu lato (in the broad sense) showing five major monophyletic lineages (genera) in red. The group containing Mariosousa, Acaciella and Faidherbia is Polytomous. I.e. It doesn't resolve into dichotomies. Faidherbia (shown in blue) is a monotypic genus that was formerly classified as Acacia albida. Original cladogram published in: Maslin, Miller & Seigler (2003), Australian Systematic Botany 16 (1): 1-18. Updated generic names follow B.R. Maslin (2006)

The five Acacia genera plus Faidherbia appear on the Kew Plant List at the following link. Most of the species have "Confidence Levels" of 2 (Medium) or 3 (High) according to Kew's Criteria For Taxonomic Integrity Of Source Data: Confidence Level Definition. You can easily look up the species placed in these genera.

  Seach Acacia, Acaciella, Vachellia, Senegalia & Mariosousa in Kew Plant List  
See Legume (Fabaceae) Subfamilies at the Palomar College Arboretum
Subfamilies:    Mimosoideae      Papilionoideae      Caesalpinioideae

Other Monocot Families With Significant Taxonomic Changes

2. Members Of The Nolinaceae & Dracaenaceae Placed In The Ruscaceae.

From a purely morphological point of view, one of the most astonishing changes is the placement of members of the Nolinaceae and Dracaenaceae into the Ruscaceae. The type genus Ruscus includes a low-growing Eurasian shrub called butcher's broom (R. aculeata) that bears no resemblance to Nolina, Dracaena & Beaucarnea. See the following image:

Ruscaceae: (A) Ruscus aculeata (Butcher's broom), a dioecious, low-growing evergreen shrub native to the Azores, western Europe, through the Mediterranean region to Iran. Each minute, scalelike leaf (red arrow) has a flattened, leaflike branchlet called a cladode or cladophyll in its axil. These cladophylls function like leaves, but they are really modified stems. (B) Beaucarnea stricta (Ponytail), and (C) Dracaena draco (dragon tree). Although these three species bear no resemblance to each other, their DNA indicates that they are closely related and members of the same family.

3. Many Monocot Genera Now Placed In Their Own Separate Families

Familiar genera such as Hyacinthus (hyacinth), Aspholelus (asphodel), Asparagus (asparagus), Allium (onion) and Iris (iris) belong to their own separate families, the Hyacinthaceae, Asphodelaceae, Asparagaceae, Alliaceae and Iridaceae. The latter family (Iridaceae) also includes the commonly cultivated Watsonia, Moraea (butterfly lily), Freesia (freesia), Sisyrinchium (blue-eyed grass), Crocus and Gladiolus. The genus Aloe, formerly of the Liliaceae, is now placed in the family Asphodelaceae, along with Kniphofia (red hot poker) and Haworthia.

Telomeres In The Order Asparagales

The large monocot order Asparagales that contains about 27,000 species (roughly10 percent of all angiosperms) has 6-base repeats of TTAGGG, the same sequence found in mammalian telomeres. This order includes many familiar plant families, such as orchids, iris, amaryllis, agave, hyacinth, asphodel, onion and asparagus. Since plants and mammals evolved into multicellular organisms along completely separate pathways, this appears to be yet another example of parallel evolution (homoplasy).

Telomeres and End Replication Problem
  Homoplasy: Parallel & Convergent Evolution  

Amaryllis (naked lady) still belongs to the Amaryllidaceae and also includes many genera that were once placed in the Liliaceae, including Crinum, Hippeastrum (amaryllis), Hymenocallis (spider lily), Haemanthus (blood lily), and Narcissus (daffodil). Agapanthus (lily of-the-Nile), Hemerocallis (day lily) and Colchicum (autumn crocus) belong to their own families, the Agapanthaceae, Hemerocallidaceae and Colchicaceae. Lilium (lily), Tulipa (tulip), Calochortus (Mariposa lily) and Fritillaria (chocolate lily) are still included in the lily family (Liliaceae). Chlorogalum (soap lily) is now placed in the agave family (Agavaceae) with Agave, Yucca, Hesperocallis (desert lily) and Camassia (camas). Death camas and star lilies (Zigadenus) are now placed in the Melanthiaceae along with Veratrum (corn lily), Trillium (trillium) and Xerophyllum (bear grass).

4. Alliaceae & Agapanthaceae (Formerly Amaryllidaceae); Hemerocallidaceae (Formerly Liliaceae)

(A) Tulbaghia violacea (society garlic) was originally placed in the amaryllis family, but DNA and chemistry data (S-containing compounds) now place it in the Alliaceae along with onions (Allium). Several oligosulfides have been identified in the Alliaceae, including methyl disulfide, dimethyl disulfide, dimethyl trisulfide, and n-propyl disulfide. When these compounds dissolve in the fluid covering the eyes they form sulfuric acid, hence the stinging eyes when slicing onions. (B) Agapanthaceae (Agapanthus), formerly in the Amaryllidaceae (amaryllis family). The original clade consisting of Agapanthus (lily of the Nile) and Amaryllidaceae had only a 63 percent bootstrap value. It was rejected by the Angiosperm Phylogeny Group (APG) and replaced by a different clade with a higher bootstrap value. Agapanthus is now placed in the Agapanthaceae and shares a common (monophyletic) ancestry with the Amaryllidaceae and Alliaceae (onion family). (C) Colorful red and yellow day lilies (Hemerocallis) were traditionally placed in the lily family (Liliaceae), but are now placed in the Hemerocallidaceae.

5. Brodiaea & Related Cormous Genera Now Placed In The Themidaceae
(Brodiaea (Brodiaea), Dichelostemma (blue dick), Bloomeria (golden stars) and Triteleia)

  Cladogram From Chis Pires & Kenneth Sytsma (2002)  

Themidaceae: A. Santa Rosa basalt brodiaea (Brodiaea santarosae), a recently described species from the Santa Rosa Plateau of Riverside County. B. Ithuriel's Spear (Triteleia laxa) from Kern County. C. Golden stars (Bloomeria crocea) in San Diego County.

A New Brodiaea From The Santa Rosa Plateau:
Santa Rosa Basalt Brodiaea MADROÑO Vol. 54: 187-198 (2007)
  Santa Rosa Basalt Brodiaea FREMONTIA Vol. 37 (2): 20-27 (2009)

Dicot Families

6. Significant Changes To The Snapdragon Family (Scrophulariaceae)

Plant Families in the Order Lamiales:


Computer generated monophyletic clades based on chloroplast DNA have resulted in major changes to the Scrophulariaceae. Plantago, Penstemon, Veronica, Linaria, Antirrhinum, Keckiella, & Digitalis are now placed in the Plantaginaceae. Mimulus with its thigmotropic stigma is placed in the Phrymaceae. Traditional genera retained in the Scropulariaceae include Verbascum and Scrophularia. Other genera placed in the Scrophulariaceae include Buddleja and Myoporum. Indian paintbrush (Castilleja), Indian warrior (Pedicularis), and owl's clover (Orthocarpus) are placed in the parasitic family Orobanchaceae with the broomrapes (Orobanche). Other closely-related families representing separate clades are the Paulowniaceae, Lentibulariaceae, Acanthaceae and Bignoniaceae. Members of the Martyniaceae (Proboscidea, Martynia & Ibicella) are included in the Pedaliaceae with Uncarina, Harpagophytum & Sesamum.

Scrophulariaceae: (A) California bee plant (Scrophularia californica ssp. floribunda), (B) butterfly bush (Buddleja davidii) and (C) prostrate myoporum (Myoporum parvifolium). Significant changes have been made to the once enormous snapdragon family (Scrophulariaceae). Traditional genera retained in the Scropulariaceae include mullein (Verbascum) and figwort (Scrophularia). Buddleja (formerly of the Loganiaceae) and Myoporum (formerly of the Myoporaceae) are now placed in the Scrophulariaceae.

Orobanchaceae: Although (A) Indian paintbrush (Castilleja affinis ssp. affinis) and (B) Indian warrior (Pedicularis densiflora) were once placed in the snapdragon family (Scrophulariaceae), they are now placed in the parasitic broom-rape family (Orobanchaceae) along with (C) chaparral broom-rape (Orobanche bulbosa). The latter holoparasitic plant is attached to the roots of chamise (Adenostoma fasciculatum)--see roots of host shrub in photo. The Orobanchaceae are considered monophyletic, including the complete parasites lacking chlorophyll (holoparasites) and the hemiparasites with green leaves (Castilleja and Pedicularis). According to Judd et al. (2008), this affinity is supported by DNA cladistic analysis, hemi to holoparasitic habit, hair morphology and possibly their racemose inflorescences.
  Wayne's Word Article On Parasitic Flowering Plants  
  Wayne's Word Article On Mycotrophic Flowering Plants  

Major DNA Changes In Plantaginaceae
Many Species Transferred From Other Plant Families
[See Globularia x indubia Planted At Palomar College
As I stated above, computer generated monophyletic clades based on chloroplast DNA have resulted in major changes to families, such as the Scrophulariaceae. For example, Plantago, Penstemon, Veronica, Linaria, Antirrhinum, Keckiella, & Digitalis are now placed in the Plantaginaceae.

Plantaginaceae: (A) Showy penstemon (Penstemon spectabilis var. spectabilis) and white-lined sphinx moth (Hyles lineata), (B) Chinese houses (Collinsia heterophylla), and (C) and foxglove (Digitalis purpurea). These common genera were formerly placed in the snapdragon family (Scrophulariaceae) but have now been transferred to the Plataginaceae.

  Hyles lineata & Penstemon spectabilis var. spectabilis  

Plantaginaceae: (A) Red-seeded plantain (Plantago rhodosperma) and (B) Nutall's snapdragon (Antirrhinum nuttalianum ssp. nutallianum. Many familiar genera of the Scrophulariaceae, such as snapdragons (Antirrhinum), Chinese houses (Collinsia), penstemons (Penstemon and Keckiella), toadflax (Linaria), and speedwell (Veronica) are now placed in the plantain family (Plantaginaceae). Plantain seeds (Plantago) are the source of the soluble fiber used in diet supplements such as Metamucil® and Hydrocil®.

2 very unlikely families that were also moved into the Plataginaceae are Hippuridaceae (including "mare's tail" Hippuris) and Callitrichaceae (including "water starwort" Callitriche). I saw water starwort in the vernal pool near Palomar College many years ago; and I saw a population of mare's tail in a marsh along the Walker River north of Bridgeport, CA. Unfortunately I cannot find images of either in my extensive Kodachrome collection.

A. Common plantain (Plantago major). B. Minute psyllium seeds seeds of the genus Plantago (including Plantago psyllium and P. ovata) are used in laxatives and soluble fiber supplements. The husk around each seed contains a water-soluble mucilaginous gum. Ground seeds (right) imbibe water and swell, forming a thick, jelly-like, mucilaginous mass of soluble fiber.

Globe Daisy On Palomar College Campus

There is a naturally occurring hybrid (cf. Globularia x indubia) between two species (G. sarcophylla and G. salicina) from the Tirajana region of Grand Canary Island. It is listed as an accepted species in the Kew Plant List. The Palomar College plant was labeled "blue eyes" which would explain the slight bluish coloration of flower heads. On-line nursery references label it G. sarcophylla; however, the above hybrid also has flower heads with bluish tinge.

Globe daisies superficially resemble small, globose daisies in the sunflower family composed of numerous disk flowers. They were long considered to be in their own family, the Globulariaceae, which was more recently merged into the huge and evergrowing family Plantaginaceae. The generic name comes from the Latin 'globulus' which means "round head" or "sphere" in reference to the spherical shape of the flower heads. When I first saw this plant in full bloom on the campus of Palomar College, I thought it was a member of the sunflower family (Asteraceae). There are numerous changes in plant names for old botanists schooled in plant taxonomy during the previous century (2nd millennium).

Phrymaceae: Red bush monkeyflower (Mimulus aurantiacus, formerly M. puniceus). This common shrub of coastal San Diego County was once placed in the snapdragon family (Scrophulariaceae). It is now placed in its own family, the Phrymaceae. The spreading stigma lobes are thigmotropic and close together with the slightest touch of your finger or an incoming pollinator, such as the bill of a hummingbird. This action decreases the chance of self pollination and favors cross pollination, especially if the incoming pollinator is covered with pollen from another monkeyflower blossom. When the bill or head of the hummingbird enters the blossom and touches the stigma it immediately closes. Pollen carried by the bird is trapped within the closed stigma lobes. As the bird probes for nectar deep in the corolla it also picks up fresh pollen from the anthers. But when it leaves, there is little chance of this newly acquired pollen touching the stigma because it is already closed, thus averting any self pollination.

Chocolate (Theobroma cacao)
7. Major Changes In The Mallow Family (Malvaceae)
The mallow family contains some of the most beautiful wildflowers in San Diego County and some economically important species, including cotton & okra. Now several additional economically important families have been merged with the Malvaceae, including the chocolate family (Sterculiaceae: Cacao & cola nut), the basswood family (Tiliaceae: Basswood & jute), and the bombax family (Bombacaceae: Kapok & balsa).

Malvaceae: A. California Ayenia (Ayenia compacta), formerly in chocolate family (Sterculiaceae). B. Cheeseweed (Malva parviflora). C. Pink Flame Tree (Brachychiton discolor), formerly in the Sterculiaceae.

Economically Important Species in the Malvaceae: Left: Kapok (Ceiba pentandra), formerly in the bombax family (Bombacaceae). Center: Okra (Hibiscus esculentus). Right: Cotton (Gossypium) tetraploid hybrid).

California Native Wildflowers in the Malvaceae: Left: Bush Mallow (Malacothamnus fasciculatus) in Palomar College Arboretum. Center: Apricot mallow (Sphaeralcea ambigua var. ambigua). Right: Desert 5-Spot (Eremalche rotundifolia).

DNA phylogenetic trees (cladograms) clearly show that the chocolate family (Sterculiaceae), basswood family (Tiliaceae), and bombax family (Bombacaceae) are not monophyletic. They are better treated as subfamilies within the mallow family (Malvaceae). This is similar to placing the duckweed subfamily Lemnoideae within the Arum family (Araceae).

Monophyletic: A taxonomic group that represents a single branch (clade) in a cladogram, and having a common ancestor. For example, all birds and reptiles are thought to have descended from a single common ancestor and are monophyletic. Humans (Homo) and chimpanzees (Pan) are also monophyletic.

  Terms Used For Taxonomic Groupings:  

8. Changes To The Martyniaceae & Pedaliaceae (APG II but not Jepson Manual)

Pedaliaceae (Martyniaceae in Jepson Manual). Two North American species of Proboscidea. These species were formerly placed in the Martyniaceae along with Martynia and Ibicella. They are now placed in the Pedaliaceae in some references, along with sesame (Sesamum indicum), Uncarina and Harpagophytum: Left. Proboscidea louisianica ssp. louisianica is a native annual in the eastern United States and is naturalized in coastal Coalifornia, including San Diego County. The yellow lines in the corolla throat are nectar guide lines that direct pollinator bees to the nectar source. Right: Proboscidea althaeifolia is a native perennial in the Colorado Desert of the southwestern United States and Baja California. It blooms during the scorching heat of July and August, long after most other desert wildflowers have bloomed and gone to seed. It occurs sparingly in Anza-Borrego Desert State Park of San Diego County.

Large, hitchhiker seed capsules of the Pedaliaceae. From left: Ibicella lutea (formerly placed in the Martyniaceae), Harpagophytum procumbens, and Uncarina grandidieri.

  Devil's Claws: Hitchhikers On Big Animals  
The Ultimate & Most Painful Hitchhikers
Sesame: An Important Seed Plant

9. A Number Of Familiar Names Have Changed In Jepson 2nd Edition

The Genus Lotus Has Been Changed To Acmispon

Deerweed (Lotus scoparius var. scoparius), a native shrubby perennial found throughout the Palomar College Arboretum and adjacent coastal sage scrub. Much to the chagrin of botanists like myself, this genus has been renamed and the new scientific trinomial is Acmispon glaber var. glaber. In the desert var. brevialatus, the keel is longer than the wings.

Cactaceae: The Cholla Cactus Genus Opuntia Has Been Changed To Cylindropuntia
Cyperaceae: Naked Stem Bulrushes Scirpus Have Been Changed To Schoenoplectus
Asteraceae: The Genus For Cheesebush Hymenolcea Has Been Changed To Ambrosia

10. Where To See Wildflowers In Southern California

Favorite Anza-Borrego SD-Riverside Witch Creek Fire California Special Santa Rosa Plateau Brodiaea Joshua Tree Marine Parasite

11. New Discoveries Continually Being Made: E.g. Brassica fruticulosa in San Diego County

  Brassica fruticulosa In San Diego Couty