photinus pyralis

from The Collaborative International Dictionary of English v.0.48

Luciferin \Lu*cif"er*in\ (l[=oo]*s[i^]f"[~e]r*[i^]n), n.
   (Biochem.)
   any of several substances found in luminescent organisms
   (such as the firefly, {Photinus pyralis}) which, when
   oxidized, produces an almost heatless light. It was first
   isolated from fireflies, and is the source of the firefly
   luminescence. See also {firefly luciferin}
   [PJC]

from The Collaborative International Dictionary of English v.0.48

Firefly \Fire"fly`\, n.; pl. {Fireflies}. (Zool.)
   Any luminous winged insect, esp. luminous beetles of the
   family {Lampyrid[ae]}.
   [1913 Webster]

   Note: The common American species belong to the genera
         {Photinus} (especially {Photinus pyralis}) and
         {Photuris}, in which both sexes are winged. The name is
         also applied to luminous species of {Elaterid[ae]}. See
         {Fire beetle}.
         [1913 Webster +PJC]

from The Collaborative International Dictionary of English v.0.48

Firefly luciferin \Fire"fly` lu*cif"er*in\, n. (Biochem.)
   a type of {luciferin} produced by the firefly {Photinus
   pyralis}.

   Note: Its structure has been elucidated, and chemically it is
         recognized as

         4,5-Dihydro-2-(6-hydroxy-2-benzothiazol-2-yl)-4-thiazolecarboxylic
         acid, {C11H8N3O2S2}. It has found use in a very
         sensitive assay for ATP, in which concentrations of ATP
         as low as 10^{-11} molar can be detected. --[MI11]
         [PJC]

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