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Triodanis perfoliata — clasping-leaved Venus'-looking-glass

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Facts

Clasping-leaved Venus'-looking-glass probably gets its name from related European species that have larger seeds with shiny mirror-like surfaces. In this species, the seeds are quite small. The Cherokee used the root to treat dyspepsia from overeating.

Habitat

Anthropogenic (man-made or disturbed habitats), cliffs, balds, or ledges, forests, ridges or ledges, talus and rocky slopes

New England distribution

Adapted from BONAP data

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North America distribution

Adapted from BONAP data

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Characteristics

Habitat
terrestrial
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont
Flower petal color
  • blue to purple
  • white
Leaf type
the leaves are simple (lobed or unlobed but not separated into leaflets)
Leaf arrangement
alternate: there is one leaf per node along the stem
Leaf blade edges
the edge of the leaf blade has teeth
Flower symmetry
there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
Number of sepals, petals or tepals
there are five petals, sepals, or tepals in the flower
Fusion of sepals and petals
the petals or the sepals are fused into a cup or tube
Stamen number
5
Fruit type (general)
the fruit is dry and splits open when ripe
Fruit length
4–6 mm
Show all characteristics
  • Clonal plantlets

    Bulbils
    the plant does not appear to have bulbils
    Bulblets replace flowers
    there are no bulblets where the flowers are located
  • Flowers

    Anther spurs
    the anthers do not have spurs on them
    Calyx symmetry
    there are two or more ways to evenly divide the calyx (the calyx is radially symmetrical)
    Carpels fused
    the carpels are fused to one another
    Cleistogamous flowers
    the plant has some cleistogamous flower
    Corolla palate
    no
    Corona lobe length
    0 mm
    Epicalyx
    the flower does not have an epicalyx
    Epicalyx number of parts
    0
    Filament length
    2–3 mm
    Flower description
    the flower has an inferior ovary, with or without a hypanthium
    Flower diameter
    8–20 mm
    Flower length
    4–13 mm
    Flower petal color
    • blue to purple
    • white
    Flower reproductive parts
    the flower has both pollen- and seed-producing parts
    Flower symmetry
    there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
    Flowers sunken into stem
    no
    Form of style
    the style is lobed at the tip, and unbranched
    Fused stamen clusters
    NA
    Fusion of sepals and petals
    the petals or the sepals are fused into a cup or tube
    Horns in hoods (Asclepias)
    NA
    Hypanthium
    the flower has a hypanthium
    Inflorescence one-sided
    the flowers are arrayed in a spiral around the inflorescence axis or branches, or occur singly, or in several ranks
    Inner tepals (Rumex)
    NA
    Interior flower disk
    the flower has an interior disc
    Marks on petals
    there are no noticeable marks on the petals
    Nectar spur
    the flower has no nectar spurs
    Number of branches in umbel
    0
    Number of carpels
    2–3
    Number of sepals, petals or tepals
    there are five petals, sepals, or tepals in the flower
    Number of styles
    1
    Ovary position
    the ovary is below the point of petal and/or sepal attachment
    Perianth shape
    the perianth is rotate (platter-shaped, the corolla flattened, circular, with nearly horizontally spreading lobes)
    Petal and sepal arrangement
    the flower includes two cycles of petal- or sepal-like structures
    Petal and sepal colors
    • blue to purple
    • white
    Petal appearance
    the petals are thin and delicate, and pigmented (colored other than green or brown)
    Petal folds or pleats
    the petals of the flower have folds or plaits on them
    Petal hairs (Viola)
    NA
    Petal hairs on inner/upper surface
    there are no hairs on the inner/upper petal surface
    Petal length
    6–8 mm
    Petal number
    5
    Petal tips (Cuscuta)
    NA
    Raceme attachment (Veronica)
    NA
    Reproductive system
    all the flowers have both carpels and stamens (synoecious)
    Scales inside corolla
    no
    Sepal and petal color
    the sepals are different from the petals
    Sepal appearance
    the sepals are green or brown, and leaf-like in texture
    Sepal appendages
    the sepals do not have appendages on them
    Sepal appendages (Oenothera)
    NA
    Sepal color
    green to brown
    Sepal length
    5–8 mm
    Sepal number
    3–5
    Sepal orientation
    the sepals are slightly curved outwards from the corolla
    Sepal relative length
    the sepal lobes are longer than the fused portion
    Sepal shape
    • the sepal outline is lanceolate (lance-shaped; narrow, gradually tapering from the base to the tip)
    • the sepal outline is roughly triangular
    Sepal texture
    the sepals are firm or rigid
    Sepal tip shape
    the sepal tip is acuminate (tapers to a very narrow point)
    Sepal uniformity
    all the sepals are about the same size
    Sepals fused only to sepals
    the sepals are fused to each other (not other flower parts), at least near their bases
    Stamen attachment
    the stamens are not attached to the petals or tepals
    Stamen length
    3.5 mm
    Stamen number
    5
    Stamen position relative to petals
    the stamens are lined up with the sepals
    Stamens fused
    the stamens are not attached to one another
    Staminodes
    there are no staminodes on the flower
    Style length
    4.5 mm
    Style petal-like
    the styles are not petal-like
    Surface of ovary
    the ovary surface is textured with tiny points, bumps or wrinkles
    Umbel flower reproductive parts
    NA
    Upper lip of bilabiate corolla
    NA
  • Fruits or seeds

    Achene relative orientation
    NA
    Achene shape
    NA
    Achene surface (Polygonum)
    NA
    Achene type
    NA
    Berry color
    NA
    Capsule color (Viola)
    NA
    Capsule splitting
    the capsule splits by three main valves, teeth or pores
    Carpel beak length
    0 mm
    Fruit (pyxis) dehiscence
    NA
    Fruit beak length
    0 mm
    Fruit cross-section
    the fruit is at least somewhat flattened
    Fruit features (Brassicaceae)
    NA
    Fruit length
    4–6 mm
    Fruit locules
    • three
    • two
    Fruit shape
    • the fruit is obloid (longer than wide and with rounded ends)
    • the fruit is obovoid (egg-shaped, but with the widest point above the middle)
    • the fruit is roughly cylindrical (with parallel sides that do not taper, and flat across the top and bottom)
    • the fruit is turbinoid (roughly shaped like a top, triangular in profile, but with a rounded end)
    Fruit type (general)
    the fruit is dry and splits open when ripe
    Fruit type (specific)
    the fruit is a capsule (splits along two or more seams, apical teeth or pores when dry, to release two or more seeds)
    Legumes (Fabaceae)
    NA
    Mericarp length
    0 mm
    Mericarp segment shape (Desmodium)
    NA
    Other markings on berry
    NA
    Ovary stipe
    the ovary or fruit does not have a stipe
    Placenta arrangement
    the plant has axile placentation, in which the ovules are attached where the septa of a compound ovary are united, usually on the central axis, or to the septa themselves
    Rows of seeds in fruit (Brassicaceae)
    NA
    Schizocarpic fruit compression
    NA
    Schizocarpic fruit segments
    0
    Seed length
    0.5–0.6 mm
    Seed relative length
    the seed is longer than it is wide
    Septum in fruit (Brassicaceae)
    NA
    Wings on fruit
    the fruit does not have wings on it
    prickles on fruits
    the fruits do not have thorn-like defensive structures
  • Glands or sap

    Glands on leaf blade
    the leaf blades do not have glandular dots or scales
    Sap
    the sap is milky and opaque, and may be white or colored
    Sap color
    the sap is white
  • Growth form

    Growth form
    the plant is an herb (it has self-supporting stems)
    Horizontal rooting stem
    the plant does not have stolons
    Lifespan
    the plant lives only a single year or less
    Parasitism
    the plant is not parasitic
    Plant color
    the leaves or young stems of the plant are green
    Plants darken when dry
    no
    Spines on plant
    the plant has no spines
    Underground organs
    there are only slender roots on the plant
  • Leaves

    Bracteole number (Apiaceae)
    0
    Bracts in plantain (Plantago)
    NA
    Final leaf segment length (compound lvs only)
    0 mm
    Final leaf segment length to width ratio (compound lvs only)
    0
    Final leaf segment width (compound lvs only)
    0 mm
    Floral bract texture
    the floral bracts are green, with a leaf-like texture
    Floral bracts
    the flower has one or more bracts associated with it
    Hairs on leaf stalk
    NA
    Hairs on underside of leaf
    the underside of the leaf is fuzzy or hairy
    Hooked hairs on underside of leaf
    no
    Inflated hairs on leaf
    the leaf blade does not have inflated hairs on it
    Leaf arrangement
    alternate: there is one leaf per node along the stem
    Leaf blade base
    the leaf has no stalk and at the base it clasps the stem
    Leaf blade base shape
    the base of the leaf blade is cordate (heart-shaped, has rounded lobes at the base)
    Leaf blade base symmetry
    the leaf blade base is symmetrical
    Leaf blade bloom
    • the underside of the leaf has no noticeable bloom
    • there is a noticeable powdery or waxy bloom on the underside of the leaf
    Leaf blade edges
    the edge of the leaf blade has teeth
    Leaf blade flatness
    the leaf is flat (planar) at the edges
    Leaf blade hairs
    the leaf blade has simple hairs with no glands, and not tangled or wooly
    Leaf blade length
    5–30 mm
    Leaf blade primary vein pattern
    the major veins radiate out from one point at the base
    Leaf blade shape
    • the leaf blade is orbicular (roughly circular, as wide as long)
    • the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
    Leaf blade surface colors
    the upper side of the leaf blade is relatively uniform in color
    Leaf duration
    the leaves drop off in winter (or they whither but persist on the plant)
    Leaf form
    the leaves are green, with an expanded blade and a leaf-like texture
    Leaf hair orientation
    the hairs are standing up straight or curved in different directions
    Leaf sheath length
    0 mm
    Leaf spines
    there are no spines on the leaf edges
    Leaf stalk
    the leaves have no leaf stalks, but attach directly to the stem
    Leaf stalk attachment to leaf
    NA
    Leaf stalk base
    NA
    Leaf stalk length
    0 mm
    Leaf teeth and lobes
    • the leaf blade margin has outward-pointing teeth
    • the leaf blade margin has rounded teeth
    Leaf tip
    the tip of the leaf blade is rounded, with no point
    Leaf type
    the leaves are simple (lobed or unlobed but not separated into leaflets)
    Leaf types
    NA
    Leaf variation
    the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem
    Leaflet number
    0
    Leaflet petiolules
    NA
    Leaves per node
    there is one leaf per node along the stem
    Pinnately compound leaf type
    NA
    Specific leaf type
    the leaves are simple (lobed or unlobed but not separated into leaflets)
    Stipels
    NA
    Stipule edges
    NA
    Stipule features
    NA
    Stipule fused to leaf stalk
    NA
    Stipule length
    0 mm
    Stipule shape
    NA
    Stipules
    there are no stipules on the plant
  • Place

    Habitat
    terrestrial
    New England state
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Rhode Island
    • Vermont
    Specific habitat
    • cliffs, balds, or ledges
    • forests
    • man-made or disturbed habitats
    • ridges or ledges
    • talus or rocky slopes
  • Stem, shoot, branch

    Branched tendrils
    NA
    Direction of stem hairs
    the hairs point mostly upwards to outwards
    Flowering stem cross-section
    the flowering stem is roughly square
    Hair between stem nodes
    • the stem has hairs between the nodes
    • the stem has no hairs between the nodes
    Hairs between stem nodes
    the hairs on the stem are plain, without glands or branches, and not tangled
    Hooked hairs on stem between nodes
    no
    Leaves on stem
    there is at least one full leaf above the base of the flowering stem
    Plant height
    1–100 cm
    Stem hair distribution
    the hairs on the stem are mainly found on the edges or angles of the stem
    Stem orientation
    the stems are upright or angled outwards
    Stem roughness between nodes
    • the stem does not feel rough
    • the stem feels rough due to hairs or prickles
    Tendril origin
    NA
    Tendrils
    the plant does not have tendrils
    Wings on stem
    the stem does not have wings on it

Wetland status

Usually occurs in non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)

In New England

Distribution

Connecticut
present
Maine
present
Massachusetts
present
New Hampshire
present
Rhode Island
present
Vermont
present

Conservation status

Exact status definitions can vary from state to state. For details, please check with your state.

Massachusetts
unranked (S-rank: SNR)
Vermont
uncommon (S-rank: S3)

var. perfoliata

Massachusetts
unranked (S-rank: SNR)

From Flora Novae Angliae dichotomous key

1.  Triodanis perfoliata (L.) Nieuwl. N

clasping-leaved Venus’-looking-glass. Legousia perfoliata (L.) Britt.; Specularia perfoliata (L.) A. DC. • CT, MA, ME, NH, RI, VT. Deciduous forests, cliff bases, rocky slopes, disturbed sites, lawns, sometimes weedy. The lower flowers of this species are cleistogamous and have a 3- or 4-merous calyx and show reduced corollas and shorter capsules compared with the chasmogamous flowers.

Native to North America?

Yes

Synonyms

  • Legousia perfoliata (L.) Britt.
  • Specularia perfoliata (L.) A. DC.

Family

Campanulaceae

Genus

Triodanis