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• Malaxis
• Malaxis unifolia

Malaxis unifolia — green adder's-mouth

Facts

Green adder's-mouth is a very small orchid with tiny, green flowers and a single leaf. Darwin noted in 1877 that in this genus (Malaxis) the flowers "though so small and inconspicuous, are highly attractive to insects…[as] shown by the pollinia [pollen sacs] having been removed from all the flowers on the spike." It is pollinated by small flies.

Habitat

Anthropogenic (man-made or disturbed habitats), swamps, wetland margins (edges of wetlands)

Characteristics

• Flowers

  Flower bract length

  0.16–1.4 mm

  Flower petal color

  • green
  • yellow

  Flower symmetry

  there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)

  Flowering date

  • August
  • July
  • June
  • September

  Flowers per inflorescence

  10–160

  Form of lower petal

  the labellum does not have a pouch-like shape

  Hairs on flower stalk

  the flower stalk has no hairs on it

  Hairs on inflorescence axis

  the main stem of the inflorescence is hairless

  Inflorescence length

  10–130 mm

  Inflorescence type

  the inflorescence is a raceme (a long unbranched stem with stalked flowers growing along it)

  Labellum position

  the labellum is in the lower position on the flower

  Length of flower stalk

  3.8–13 mm

  Length of narrowed base of lower petal

  0 mm

  Lobes at base of lower petal

  0.4–1.1 mm

  Lower petal characteristics

  the labellum is lobed

  Lower petal length

  1.1–2.3 mm

  Lower petal outline

  the labellum is lobed but not fringed

  Lower petal strongly red-veined

  no

  Main color of lower petal

  • blue to purple
  • green to brown
  • yellow

  Nectar spur

  there are no nectar spurs on the flower

  Nectar spur length

  0 mm

  Number of stamens

  1

  Orientation of side petals

  the lateral petals slant somewhat downward

  Pollen sacs

  the pollinia remain intact and do not fragment into smaller parts

  Self-pollinating flowers

  there are no cleistogamous flowers on this plant

  Sepal length

  1.1–2.2 mm

  Sepals fused only to sepals

  the sepals are separate from one another

  Spots on lower petal

  no

  Spur opening membrane

  NA

  Spur opening shape

  NA

• Fruits or seeds

  Seed capsule orientation

  • the capsule bends downwards or hangs downwards
  • the capsule points upwards or is angled outwards

• Growth form

  Plant green or not

  the plant is chlorophyllous (it has green parts)

  Roots

  the rhizomes do not resemble coral

  Underground organs

  • the plant has one or more swollen storage organs underground, such as bulbs, tubers or corms
  • there are only slender roots on the plant

• Leaves

  Bract relative length

  the bract is shorter than the associated flower

  Features of leaves

  the leaf does not have any of the mentioned special features

  Leaf arrangement

  alternate: there is one leaf per node along the stem

  Leaf blade edges

  the edges of the leaf blade have no teeth

  Leaf blade length

  16–100 mm

  Leaf blade length to width ratio

  2–3

  Leaf blade shape

  the leaf blade is ovate (widest below the middle and broadly tapering at both ends)

  Leaf blade tip

  the tip of the leaf blade is acute (sharply pointed)

  Leaf blade width

  5–50 mm

  Leaves during flowering

  there are leaves on the plant when it is flowering

  Number of leaves on stem

  • one
  • two

• Place

  Habitat

  • terrestrial
  • wetlands

  New England state

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

  Specific habitat

  • edges of wetlands
  • man-made or disturbed habitats
  • swamps

Wetland status

Occurs in wetlands or non-wetlands. (Wetland indicator code: FAC)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae