Correlation of bioluminescence emissions with ventral photophores in the mesopelagic squidAbralia veranyi (Cephalopoda: Enoploteuthidae)

Specimens of the squidAbralia veranyi were collected off the Bahamas in 1989. The bioluminescence of the ventral photophores was recorded on videotape at 11 to 12°C and 24°C, in conjunction with measurements of the spectral emission at the same temperatures. At 11 °C, the spectrum was unimodal, peaking at 490 nm with a narrow bandwidth. At the higher temperature a shoulder at about 440 nm appeared in the emission spectrum. The short, bright flashes from the subocular photophores had a broader bandwidth and a shorter wavelength emission maximum (475 nm) than that of the ventral photophores. Video recordings at the two temperatures showed no changes in either the identities of the luminescing photophores or their relative intensities. One structurally distinct type of photophore was not illuminated. We conclude that the observed spectral changes were produced within one group of photophores, and that recruitment of the unilluminated photophores would produce an additional spectral component, previously reported from another species ofAbralia (A. trigonura).