TY - JOUR

T1 - The lens eyes of the box jellyfish Tripedalia cystophora and Chiropsalmus sp. are slow and color-blind

AU - Garm, A

AU - Coates, M M

AU - Gad, R

AU - Seymour, J

AU - Nilsson, D-E

N1 - Keywords: Animals; Color Perception; Color Vision Defects; Cubozoa; Electrophysiology; Eye; Female; Light; Male; Photoreceptor Cells, Invertebrate

PY - 2007

Y1 - 2007

N2 - Box jellyfish, or cubomedusae, possess an impressive total of 24 eyes of four morphologically different types. Compared to other cnidarians they also have an elaborate behavioral repertoire, which for a large part seems to be visually guided. Two of the four types of cubomedusean eyes, called the upper and the lower lens eye, are camera type eyes with spherical fish-like lenses. Here we explore the electroretinograms of the lens eyes of the Caribbean species, Tripedalia cystophora, and the Australian species, Chiropsalmus sp. using suction electrodes. We show that the photoreceptors of the lens eyes of both species have dynamic ranges of about 3 log units and slow responses. The spectral sensitivity curves for all eyes peak in the blue-green region, but the lower lens eye of T. cystophora has a small additional peak in the near UV range. All spectral sensitivity curves agree well with the theoretical absorbance curve of a single opsin, strongly suggesting color-blind vision in box jellyfish with a single receptor type. A single opsin is supported by selective adaptation experiments.

AB - Box jellyfish, or cubomedusae, possess an impressive total of 24 eyes of four morphologically different types. Compared to other cnidarians they also have an elaborate behavioral repertoire, which for a large part seems to be visually guided. Two of the four types of cubomedusean eyes, called the upper and the lower lens eye, are camera type eyes with spherical fish-like lenses. Here we explore the electroretinograms of the lens eyes of the Caribbean species, Tripedalia cystophora, and the Australian species, Chiropsalmus sp. using suction electrodes. We show that the photoreceptors of the lens eyes of both species have dynamic ranges of about 3 log units and slow responses. The spectral sensitivity curves for all eyes peak in the blue-green region, but the lower lens eye of T. cystophora has a small additional peak in the near UV range. All spectral sensitivity curves agree well with the theoretical absorbance curve of a single opsin, strongly suggesting color-blind vision in box jellyfish with a single receptor type. A single opsin is supported by selective adaptation experiments.

U2 - 10.1007/s00359-007-0211-4

DO - 10.1007/s00359-007-0211-4

M3 - Journal article

C2 - 17541674

VL - 193

SP - 547

EP - 557

JO - Journal of Comparative Physiology A: Neuroethology, Sensory, Neural, and Behavioral Physiology

JF - Journal of Comparative Physiology A: Neuroethology, Sensory, Neural, and Behavioral Physiology

SN - 0340-7594

IS - 5

ER -