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- Pedaliaceae
- Proboscidea
- Proboscidea louisianica
Proboscidea louisianica — ram's-horn
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New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
Found this plant? Take a photo and post a sighting.
Facts
Ram's-horn (aka Louisiana unicorn-plant) is native to the south-central U. S. and introduced in New England, where it can be found in fields and cultivated areas. This is one of only a few species in the Pediliaceae in our region. It gets its common name from the curving horn-shaped pod; the pod contains pigments that have been used in traditional black dyes for basketry by the Shoshoni and other Native American tribes.
Habitat
Anthropogenic (man-made or disturbed habitats), meadows and fields
Characteristics
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Massachusetts
- Rhode Island
- Vermont
- Flower petal color
-
- white
- yellow
- Leaf type
- the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
- Leaf arrangement
-
- alternate: there is one leaf per node along the stem
- opposite: there are two leaves per node along the stem
- Leaf blade edges
- the edge of the leaf blade is entire (has no teeth or lobes)
- Flower symmetry
- there is only one way to evenly divide the flower (the flower is bilaterally 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
- 4
- Fruit length
- 100–200 mm
-
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 is only one way to evenly divide the calyx (the calyx is bilaterally symmetrical)
- Cleistogamous flowers
- there are no cleistogamous flowers on the plan
- Corolla palate
- no
- Corona lobe length
- 0 mm
- Epicalyx number of parts
- 0
- Flower description
- the flower has a superior ovary, and lacks a hypanthium
- Flower number
- 8–20
- Flower petal color
-
- white
- yellow
- Flower reproductive parts
- the flower has both pollen- and seed-producing parts
- Flower symmetry
- there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)
- Flowers sunken into stem
- no
- Form of style
- the style is lobed at the tip, and unbranched
- Fusion of sepals and petals
- the petals or the sepals are fused into a cup or tube
- Horns in hoods (Asclepias)
- NA
- Inner tepals (Rumex)
- NA
- Marks on petals
- the petals have spots or streaks on them
- Nectar spur
- the flower has no nectar spurs
- Number of carpels
- 2
- Number of pistils
- 1
- 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 above the point of petal and/or sepal attachment
- Petal and sepal arrangement
- the flower includes two cycles of petal- or sepal-like structures
- Petal and sepal colors
-
- white
- yellow
- Petal appearance
- the petals are thin and delicate, and pigmented (colored other than green or brown)
- Petal hairs (Viola)
- NA
- Petal length
- 35–55 mm
- Petal number
- 5
- Petal tips (Cuscuta)
- NA
- Scales inside corolla
- no
- Sepal and petal color
- the sepals are different from the petals
- Sepal appendages
- the sepals do not have appendages on them
- Sepal appendages (Oenothera)
- NA
- Sepal number
- 5
- 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 attached at or near the bases of the petals or tepals
- Stamen number
- 4
- Stamen position relative to petals
- the stamens are lined up with the sepals
- Staminodes
- the flower has staminodes
- Stigma position
- the stigmas are positioned at the tip of the style
- Style petal-like
- the styles are not petal-like
- Umbel flower reproductive parts
- NA
-
Fruits or seeds
- Achene shape
- NA
- Achene surface (Polygonum)
- NA
- Capsule color (Viola)
- NA
- Fruit (pyxis) dehiscence
- NA
- Fruit features (Brassicaceae)
- NA
- Fruit length
- 100–200 mm
- Fruit locules
- one
- 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 segment shape (Desmodium)
- NA
- Other markings on berry
- NA
- Rows of seeds in fruit (Brassicaceae)
- NA
- Schizocarpic fruit compression
- NA
- Schizocarpic fruit segments
- 0
- Septum in fruit (Brassicaceae)
- NA
- prickles on fruits
-
- the fruits are armed with thorns-like defensive structures
- 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 clear and watery
- Sap color
- the sap is clear
-
Growth form
- Growth form
- the plant is an herb (it has self-supporting stems)
- 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
- there are spines on the plant
-
Leaves
- Bracteole number (Apiaceae)
- 0
- Bracts in plantain (Plantago)
- NA
- Final leaf segment length (compound lvs only)
- 0 mm
- Hairs on underside of leaf
- the underside of the leaf is fuzzy or hairy
- Hairs on upper side of leaf
- the upper side of the leaf is fuzzy or hairy
- Leaf arrangement
-
- alternate: there is one leaf per node along the stem
- opposite: there are two leaves per node along the stem
- Leaf blade base
- the leaf has a distinct leaf stalk (petiole)
- Leaf blade base shape
- the base of the leaf blade is cordate (heart-shaped, has rounded lobes at the base)
- Leaf blade edges
- the edge of the leaf blade is entire (has no teeth or lobes)
- Leaf blade length
- Up to 250 mm
- Leaf blade shape
-
- the leaf blade is cordate (heart-shaped with backward-facing rounded lobes), or sagittate (arrow-shaped with backward-facing pointed lobes)
- the leaf blade is orbicular (roughly circular, as wide as long)
- the leaf blade is reniform (kidney-shaped; wider than long)
- 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 spines
- there are no spines on the leaf edges
- Leaf stalk
- the leaves have leaf stalks
- Leaf teeth and lobes
-
- the edge of the leaf blade is entire (has no teeth or lobes)
- the leaf blade margin is wavy, but does not have teeth
- Leaf type
- the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
- Leaves per node
-
- there are two leaves per node along the stem
- there is one leaf per node along the stem
- Specific leaf type
- the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
- Stipule features
- NA
- Stipules
- there are no stipules on the plant
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Massachusetts
- Rhode Island
- Vermont
- Specific habitat
-
- man-made or disturbed habitats
- meadows or fields
-
Stem, shoot, branch
- Branched tendrils
- NA
- Hair between stem nodes
- the stem has hairs between the nodes
- Hairs between stem nodes
- at least some of the hairs on the stem have glands
- Plant height
- At least 60 cm
- Tendril origin
- NA
- Tendrils
- the plant does not have tendrils
Wetland status
Not classified
New England distribution and conservation status
Distribution
- Connecticut
- present
- Maine
- absent
- Massachusetts
- present
- New Hampshire
- absent
- Rhode Island
- present
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Massachusetts
- not applicable (S-rank: SNA)
ssp. louisianica
- Massachusetts
- unranked (S-rank: SNR)
Native to North America?
Yes and no (some introduced)
Sometimes confused with
- Sesamum orientale:
- flowers solitary in the axils of leaves, corolla 15–33 mm long, and fruit 2–3 cm long, tipped by a short, broad, straight beak that is ultimately split into two halves (vs. P. louisianica, with flowers in mostly 8- to 20-flowered racemes, corolla 35–55 mm long, nad fruit 10–20 cm long, tipped by long, arching, horn-like beak that is ultimately split into two halves).
Synonyms
- Martynia louisianica P. Mill.
Family
Genus
Notes on subspecies and varieties in New England
Our subspecies is Proboscidea louisianica (P. Mill.) Thellung ssp. louisianica.
From the dichotomous key of Flora Novae Angliae
1. Proboscidea louisianica (P. Mill.) Thellung ssp. louisianica E
ram’s-horn. Martynia louisianica P. Mill. • CT, MA, RI, VT; also reported from ME and NH by Kartesz (1999), but specimens are unknown. Fields, areas of cultivation.