Morphology of the light-organ system and bioluminescent blinking in the ponyfish tribe Equulitini (Teleostei: Leiognathidae)
Fig 5
Male Equulites elongatus light organ in posterior view.
(A) Light organ in posterior view from anterior gas bladder in situ (SIO 96−98, 83.1 mm SL) with screening tissues retracted. (B) Dorsoposterior view of excised light organ, esophagus, and anterior stomach (AMNH PVD 82-0/19a, 76.3 mm SL) with ventral screening band of tissue partially extended. (C) Diagrammatic light organs in left posterolateral view. Left image shows an unobscured translucent window into the gas bladder similar to photo in (A). Middle image shows a translucent window with shutter partially covering window with tissue containing separated chromatocytes and iridocytes similar to photo in (B). Right image shows a translucent window with shutter covering window obscuring light into the gas bladder. Orange oval indicates window into gas bladder. Blue arrows indicate direction and degree of longitudinal muscle contraction. Abbreviations: connective tissue (ct), esophagus (es), longitudinal muscle (lm), stomach (st). Photographs taken by M.J.G. and are original to this work.