Pinguicula elizabethiae
Encyclopedia
Pinguicula elizabethiae is a perennial rosette
-forming insectivorous
herb
native to the Mexican states of Querétaro
and Hidalgo. A species of butterwort, it forms summer rosettes
of flat, succulent leaves up to 5 centimeters (4 in) long, which are covered in mucilage
nous (sticky) glands that attract, trap, and digest arthropod
prey. Nutrients derived from the prey are used to supplement the nutrient-poor substrate
that the plant grows in. In the winter the plant forms a non-carnivorous rosette of small, fleshy leaves that conserves energy while food and moisture supplies are low. Single purple flowers appear between July and October on upright stalks up to 75 millimeters long.
The species was described in 1999 by S. Zamudio, who placed in the section Orcheosanthus. It is closely related to P. colimensis.
The generic name Pinguicula is derived from the Latin pinguis (meaning "fat") due to the buttery texture of the surface of the carnivorous leaves. The specific epithet elizabethiae refers to Zamudio's friend Elizabeth Arguelles, an enthusiastic collector of flora from Querétaro.
–spatulate
to suborbicular
–spatulate
leaves. These leaves are carnivorous, having a large surface area densely covered with stalked mucilagenous glands with which they attract, trap, and digest arthropod prey, most commonly flies
. These so-called "summer leaves" are replaced by "winter rosettes" of small, glandless succulent leaves with the onset of the dry season in late fall. This protective winter rosette allows the plant to undergo winter dormancy
until the first rains begin in spring. Flowers born singly on upright 35–75 millimeter (–3 in.) peduncles
emerge from July–October.
are generally obovate
–spatulate
to suborbicular
–spatulate
, between 35 and 72 millimeters (–3 in.) long and 10–53 millimeters (⅜–2 in.) wide, and have slightly involute
margins. The leaf bases are covered in 5–10 millimeter multicellular trichome
s.
The "winter" or "resting
" rosette of P. elizabethiae is 10–20 millimeters (⅜– in.) in diameter and consists of 60 to 125 small, compact, fleshy, non-glandular leaves. These are each 5 to 17 millimeters (– in.) long and two to four millimeters (– in.) wide, spatulate
to oblong-spatulate
, obtuse, and densely covered with 5–10 millimeter multicellular trichome
s.
As is typical in the genus, the upper lamina surface of the summer leaves is densely covered by peduncular (stalked) mucilage
nous gland
s and sessile
(flat) digestive glands. The peduncular glands consist of a few secretory cells on top of a single-celled stalk. These cells produce a mucilagenous secretion which forms visible droplets across the leaf surface. This wet appearance probably helps lure prey in search of water; a similar phenomenon is observed in the sundew
s. The droplets secrete only limited enzymes and serve mainly to entrap insects. On contact with an insect, the peduncular glands release additional mucilage from special reservoir cells located at the base of their stalks. The insect struggles, triggering more glands and encasing itself in mucilage. The sessile glands, which lie flat on the leaf surface, serve to digest the insect prey. Once the prey is entrapped by the peduncular glands and digestion begins, the initial flow of nitrogen triggers enzyme release by the sessile glands. These enzymes, which include amylase
, esterase
, phosphatase
, protease
, and ribonuclease
break down the digestible components of the insect body. These fluids are then absorbed back into the leaf surface through cuticular
holes, leaving only the chitin
exoskeleton
of the larger insects on the leaf surface.
s during each flowering period. These are borne singly on upright flower stalks which are 3.5 to 7.5 centimeters (–3 in.) long and are covered in glandular trichomes. Most flowers are pinkish, but colors ranging from violet to off-white have been observed.
The flowers themselves are composed of five petal
s which are fused at one end. The throat, the portion of the flower near the attachment point which holds the reproductive organs, is funnel shaped, and the petals flare out from there into a five-lobed zygomorphic corolla. Below the attachment point to the stem the petals are fused into a 15–28 millimeter (⅝– in.) long spur which protrudes backwards roughly perpendicular to the rest of the flower.
The flowers are 36 to 46 millimeters (– in.) long, and have a deeply bilabiate corolla, with an 2-lobed upper lip and a 3-lobed lower lip. The upper lobes are 6.5–10 millimeters (¼–⅜ in.) long by 7–10.5 millimeters (¼–⅜ in.) wide and generally obovate to suborbicular. The outer lower lobes are similarly shaped and are 7–13 millimeters (¼–¾ in.) in both width and length, though the central lobe tends to be slightly longer than its neighbors. The floral tube that houses the reproductive organs and is visible at the base of the corolla lobes is 4–5 millimeters (– in.) long and is green to white. The white color can sometimes extend partway onto the lower petal lobes, especially as a stripe on the central lobe.
The ovary and attached pistil protrude from the top of the floral tube near its opening, with the receptive stigma
surface toward the front. Anthers hang from recurved filaments behind the pistil. Pollinators exiting after collecting nectar from the spur brush against the anther, transferring pollen to the stigma of the next flower they visit. The flowers can last up to 10 days but will wilt once they are pollinated. Pollinated ovaries ripen into 2–3.7 millimeter (– in.) dehiscent seed capsules containing numerous 0.8–1 millimeter long, 2 millimeter wide seeds.
and its tributary Arroyo Toliman, and may therefore represent a new endemic species for the canyon system. Here it grows on steep slopes and vertical cliffs facing north to north-east, at an altitude of 1000–1600 meters (3300–5250 ft.). Surrounding vegetation is submontane, and companion plants include Selaginella lepidophylla
, Notholaena
sp., Cheilanthes sp. and moss
es.
in 1990. Ortega, not realizing he had discovered a new taxon, identified his collections as the somewhat similar P. cyclosecta. Mexican botanist Sergio Zamudio Ruiz observed the same population and others nearby in 1996, and came to the same conclusion. A third botanist, Johan van Marm, then indicated that he had also observed Pinguicula in the canyon system, but assumed he had discovered a range extension for P. colimensis. In 1998 Zamudio had the opportunity of comparing the two established species with the plants from the Moctezuma River and Arroyo Toliman canyon systems, and concluded that they were indeed three distinct species. P. elizabethiae was described in 1999 and placed in the section Orcheosanthus along with other species with purple, deeply bilabiate corollas with 5 sub-equal lobes, a short floral tube, and a large spur not protruding past this tube. Morphological similarities have been noted between this species and P. colimensis and P. cyclosecta, though differences in the size and shape of the summer leaves, presence of large multi-cellular trichomes at the leaf base, and other morphological features can be used to distinguish the geographically isolated species in cultivation.
Rosette (botany)
In botany, a rosette is a circular arrangement of leaves, with all the leaves at a single height.Though rosettes usually sit near the soil, their structure is an example of a modified stem.-Function:...
-forming insectivorous
Carnivorous plant
Carnivorous plants are plants that derive some or most of their nutrients from trapping and consuming animals or protozoans, typically insects and other arthropods. Carnivorous plants appear adapted to grow in places where the soil is thin or poor in nutrients, especially nitrogen, such as acidic...
herb
Herbaceous
A herbaceous plant is a plant that has leaves and stems that die down at the end of the growing season to the soil level. They have no persistent woody stem above ground...
native to the Mexican states of Querétaro
Querétaro
Querétaro officially Estado Libre y Soberano de Querétaro de Arteaga is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided into 18 municipalities and its capital city is Santiago de Querétaro....
and Hidalgo. A species of butterwort, it forms summer rosettes
Rosette (botany)
In botany, a rosette is a circular arrangement of leaves, with all the leaves at a single height.Though rosettes usually sit near the soil, their structure is an example of a modified stem.-Function:...
of flat, succulent leaves up to 5 centimeters (4 in) long, which are covered in mucilage
Mucilage
Mucilage is a thick, gluey substance produced by most plants and some microorganisms. It is a polar glycoprotein and an exopolysaccharide.It occurs in various parts of nearly all classes of plant, usually in relatively small percentages, and is frequently associated with other substances, such as...
nous (sticky) glands that attract, trap, and digest arthropod
Arthropod
An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...
prey. Nutrients derived from the prey are used to supplement the nutrient-poor substrate
Substrate (biology)
In biology a substrate is the surface a plant or animal lives upon and grows on. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock can be substrate for another animal that lives on top of the algae. See also substrate .-External...
that the plant grows in. In the winter the plant forms a non-carnivorous rosette of small, fleshy leaves that conserves energy while food and moisture supplies are low. Single purple flowers appear between July and October on upright stalks up to 75 millimeters long.
The species was described in 1999 by S. Zamudio, who placed in the section Orcheosanthus. It is closely related to P. colimensis.
The generic name Pinguicula is derived from the Latin pinguis (meaning "fat") due to the buttery texture of the surface of the carnivorous leaves. The specific epithet elizabethiae refers to Zamudio's friend Elizabeth Arguelles, an enthusiastic collector of flora from Querétaro.
Plant characteristics
Habit and Phenology
Like many Mexican butterworts, P. elizabethiae is seasonally dimorphic, in that it undergoes two distinct growth habits throughout the year. During the summer when rain and insect prey are most plentiful, the plant forms a ground hugging rosette up to 12 centimeters (5 in) in diameter and composed of obovateLeaf shape
In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...
–spatulate
Leaf shape
In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...
to suborbicular
Leaf shape
In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...
–spatulate
Leaf shape
In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...
leaves. These leaves are carnivorous, having a large surface area densely covered with stalked mucilagenous glands with which they attract, trap, and digest arthropod prey, most commonly flies
Diptera
Diptera , or true flies, is the order of insects possessing only a single pair of wings on the mesothorax; the metathorax bears a pair of drumstick like structures called the halteres, the remnants of the hind wings. It is a large order, containing an estimated 240,000 species, although under half...
. These so-called "summer leaves" are replaced by "winter rosettes" of small, glandless succulent leaves with the onset of the dry season in late fall. This protective winter rosette allows the plant to undergo winter dormancy
Dormancy
Dormancy is a period in an organism's life cycle when growth, development, and physical activity are temporarily stopped. This minimizes metabolic activity and therefore helps an organism to conserve energy. Dormancy tends to be closely associated with environmental conditions...
until the first rains begin in spring. Flowers born singly on upright 35–75 millimeter (–3 in.) peduncles
Peduncle (botany)
In botany, a peduncle is a stem supporting an inflorescence, or after fecundation, an infructescence.The peduncle is a stem, usually green and without leaves, though sometimes colored or supporting small leaves...
emerge from July–October.
Leaves and stolons
The leaf blades of the summer rosettes of P. elizabethiae are smooth, rigid, and succulent, and green in color. The laminaeLeaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
are generally obovate
Leaf shape
In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...
–spatulate
Leaf shape
In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...
to suborbicular
Leaf shape
In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...
–spatulate
Leaf shape
In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...
, between 35 and 72 millimeters (–3 in.) long and 10–53 millimeters (⅜–2 in.) wide, and have slightly involute
Involute
In the differential geometry of curves, an involute is a curve obtained from another given curve by attaching an imaginary taut string to the given curve and tracing its free end as it is wound onto that given curve; or in reverse, unwound. It is a roulette wherein the rolling curve is a straight...
margins. The leaf bases are covered in 5–10 millimeter multicellular trichome
Trichome
Trichomes are fine outgrowths or appendages on plants and certain protists. These are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae.- Algal trichomes :...
s.
The "winter" or "resting
Estivation
Aestivation is a state of animal dormancy, characterized by inactivity and a lowered metabolic rate, that is entered in response to high temperatures and arid conditions...
" rosette of P. elizabethiae is 10–20 millimeters (⅜– in.) in diameter and consists of 60 to 125 small, compact, fleshy, non-glandular leaves. These are each 5 to 17 millimeters (– in.) long and two to four millimeters (– in.) wide, spatulate
Leaf shape
In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...
to oblong-spatulate
Leaf shape
In botany, leaf shape is characterised with the following terms :* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...
, obtuse, and densely covered with 5–10 millimeter multicellular trichome
Trichome
Trichomes are fine outgrowths or appendages on plants and certain protists. These are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae.- Algal trichomes :...
s.
As is typical in the genus, the upper lamina surface of the summer leaves is densely covered by peduncular (stalked) mucilage
Mucilage
Mucilage is a thick, gluey substance produced by most plants and some microorganisms. It is a polar glycoprotein and an exopolysaccharide.It occurs in various parts of nearly all classes of plant, usually in relatively small percentages, and is frequently associated with other substances, such as...
nous gland
Gland
A gland is an organ in an animal's body that synthesizes a substance for release of substances such as hormones or breast milk, often into the bloodstream or into cavities inside the body or its outer surface .- Types :...
s and sessile
Sessility (botany)
In botany, sessility is a characteristic of plants whose flowers or leaves are borne directly from the stem or peduncle, and thus lack a petiole or pedicel...
(flat) digestive glands. The peduncular glands consist of a few secretory cells on top of a single-celled stalk. These cells produce a mucilagenous secretion which forms visible droplets across the leaf surface. This wet appearance probably helps lure prey in search of water; a similar phenomenon is observed in the sundew
Sundew
Drosera, commonly known as the sundews, comprise one of the largest genera of carnivorous plants, with at least 194 species. These members of the family Droseraceae lure, capture, and digest insects using stalked mucilaginous glands covering their leaf surface. The insects are used to supplement...
s. The droplets secrete only limited enzymes and serve mainly to entrap insects. On contact with an insect, the peduncular glands release additional mucilage from special reservoir cells located at the base of their stalks. The insect struggles, triggering more glands and encasing itself in mucilage. The sessile glands, which lie flat on the leaf surface, serve to digest the insect prey. Once the prey is entrapped by the peduncular glands and digestion begins, the initial flow of nitrogen triggers enzyme release by the sessile glands. These enzymes, which include amylase
Amylase
Amylase is an enzyme that catalyses the breakdown of starch into sugars. Amylase is present in human saliva, where it begins the chemical process of digestion. Food that contains much starch but little sugar, such as rice and potato, taste slightly sweet as they are chewed because amylase turns...
, esterase
Esterase
An esterase is a hydrolase enzyme that splits esters into an acid and an alcohol in a chemical reaction with water called hydrolysis.A wide range of different esterases exist that differ in their substrate specificity, their protein structure, and their biological function.- EC classification/list...
, phosphatase
Phosphatase
A phosphatase is an enzyme that removes a phosphate group from its substrate by hydrolysing phosphoric acid monoesters into a phosphate ion and a molecule with a free hydroxyl group . This action is directly opposite to that of phosphorylases and kinases, which attach phosphate groups to their...
, protease
Protease
A protease is any enzyme that conducts proteolysis, that is, begins protein catabolism by hydrolysis of the peptide bonds that link amino acids together in the polypeptide chain forming the protein....
, and ribonuclease
Ribonuclease
Ribonuclease is a type of nuclease that catalyzes the degradation of RNA into smaller components. Ribonucleases can be divided into endoribonucleases and exoribonucleases, and comprise several sub-classes within the EC 2.7 and 3.1 classes of enzymes.-Function:All organisms studied contain...
break down the digestible components of the insect body. These fluids are then absorbed back into the leaf surface through cuticular
Plant cuticle
Plant cuticles are a protective waxy covering produced only by the epidermal cells of leaves, young shoots and all other aerial plant organs without periderm...
holes, leaving only the chitin
Chitin
Chitin n is a long-chain polymer of a N-acetylglucosamine, a derivative of glucose, and is found in many places throughout the natural world...
exoskeleton
Exoskeleton
An exoskeleton is the external skeleton that supports and protects an animal's body, in contrast to the internal skeleton of, for example, a human. In popular usage, some of the larger kinds of exoskeletons are known as "shells". Examples of exoskeleton animals include insects such as grasshoppers...
of the larger insects on the leaf surface.
Flowers
P. elizabethiae produces one to five flowerFlower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s during each flowering period. These are borne singly on upright flower stalks which are 3.5 to 7.5 centimeters (–3 in.) long and are covered in glandular trichomes. Most flowers are pinkish, but colors ranging from violet to off-white have been observed.
The flowers themselves are composed of five petal
Petal
Petals are modified leaves that surround the reproductive parts of flowers. They often are brightly colored or unusually shaped to attract pollinators. Together, all of the petals of a flower are called a corolla. Petals are usually accompanied by another set of special leaves called sepals lying...
s which are fused at one end. The throat, the portion of the flower near the attachment point which holds the reproductive organs, is funnel shaped, and the petals flare out from there into a five-lobed zygomorphic corolla. Below the attachment point to the stem the petals are fused into a 15–28 millimeter (⅝– in.) long spur which protrudes backwards roughly perpendicular to the rest of the flower.
The flowers are 36 to 46 millimeters (– in.) long, and have a deeply bilabiate corolla, with an 2-lobed upper lip and a 3-lobed lower lip. The upper lobes are 6.5–10 millimeters (¼–⅜ in.) long by 7–10.5 millimeters (¼–⅜ in.) wide and generally obovate to suborbicular. The outer lower lobes are similarly shaped and are 7–13 millimeters (¼–¾ in.) in both width and length, though the central lobe tends to be slightly longer than its neighbors. The floral tube that houses the reproductive organs and is visible at the base of the corolla lobes is 4–5 millimeters (– in.) long and is green to white. The white color can sometimes extend partway onto the lower petal lobes, especially as a stripe on the central lobe.
The ovary and attached pistil protrude from the top of the floral tube near its opening, with the receptive stigma
Stigma (botany)
The stigma is the receptive tip of a carpel, or of several fused carpels, in the gynoecium of a flower. The stigma receives pollen at pollination and it is on the stigma that the pollen grain germinates. The stigma is adapted to catch and trap pollen with various hairs, flaps, or sculpturings...
surface toward the front. Anthers hang from recurved filaments behind the pistil. Pollinators exiting after collecting nectar from the spur brush against the anther, transferring pollen to the stigma of the next flower they visit. The flowers can last up to 10 days but will wilt once they are pollinated. Pollinated ovaries ripen into 2–3.7 millimeter (– in.) dehiscent seed capsules containing numerous 0.8–1 millimeter long, 2 millimeter wide seeds.
Distribution and habitat
P. elizabethia is currently known from only a handful of sites in the canyons of Moctezuma riverMoctezuma River
-References:*Atlas of Mexico, 1975 .*The Prentice Hall American World Atlas, 1984.*Rand McNally, The New International Atlas, 1993....
and its tributary Arroyo Toliman, and may therefore represent a new endemic species for the canyon system. Here it grows on steep slopes and vertical cliffs facing north to north-east, at an altitude of 1000–1600 meters (3300–5250 ft.). Surrounding vegetation is submontane, and companion plants include Selaginella lepidophylla
Selaginella lepidophylla
Selaginella lepidophylla is a species of desert plant in the spikemoss family . S. lepidophylla is noted for its ability to survive almost complete desiccation; during dry weather in its native habitat, its stems curl into a tight ball and uncurl when exposed to moisture...
, Notholaena
Notholaena
Notholaena is a genus of ferns in the family Pteridaceae found exclusively in the New World. Ferns of this genus are mostly epipetric or occurring in coarse, gravelly soils, and are most abundant and diverse in the mountain ranges of warm arid or semiarid regions...
sp., Cheilanthes sp. and moss
Moss
Mosses are small, soft plants that are typically 1–10 cm tall, though some species are much larger. They commonly grow close together in clumps or mats in damp or shady locations. They do not have flowers or seeds, and their simple leaves cover the thin wiry stems...
es.
Taxonomy
P. elizabethiae was first collected by Ricardo Zirahuen Ortega from the Moctezuma River canyon during an environmental impact assessment survey for the Zimapán DamZimapán Dam
The Zimapán Dam, also known as Fernando Hiriart Balderrama Dam, is an arch dam on the Moctezuma River about southwest of Zimapán in Hidalgo state, Mexico...
in 1990. Ortega, not realizing he had discovered a new taxon, identified his collections as the somewhat similar P. cyclosecta. Mexican botanist Sergio Zamudio Ruiz observed the same population and others nearby in 1996, and came to the same conclusion. A third botanist, Johan van Marm, then indicated that he had also observed Pinguicula in the canyon system, but assumed he had discovered a range extension for P. colimensis. In 1998 Zamudio had the opportunity of comparing the two established species with the plants from the Moctezuma River and Arroyo Toliman canyon systems, and concluded that they were indeed three distinct species. P. elizabethiae was described in 1999 and placed in the section Orcheosanthus along with other species with purple, deeply bilabiate corollas with 5 sub-equal lobes, a short floral tube, and a large spur not protruding past this tube. Morphological similarities have been noted between this species and P. colimensis and P. cyclosecta, though differences in the size and shape of the summer leaves, presence of large multi-cellular trichomes at the leaf base, and other morphological features can be used to distinguish the geographically isolated species in cultivation.