Topic
Uca pugilator
About: Uca pugilator is a research topic. Over the lifetime, 376 publications have been published within this topic receiving 12303 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: The phase relationship of the two processes appears to be regulated in an antagonistic manner as those eyestalk-ablated lobsters exhibiting an accelerated molting cycle show correspondingly small gonadal development while those showing great gonadal growth do not exhibit accelerated molts.
50 citations
TL;DR: A female-limited lipoprotein is found in the hemolymph of only those individuals with maturing oocytes in the fiddler crab, Uca pugilator, and there is no difference between the electrophoretic patterns of hemocyanin from males and females.
Abstract: 1. 1. A female-limited lipoprotein is found in the hemolymph of only those individuals with maturing oocytes. The relative concentration of the lipoprotein in the ovary increases progressively with oocyte maturation. 2. 2. There is no difference between the electrophoretic patterns of hemocyanin from males and females. 3. 3. The electrophoretic pattern of the hemocyanin components is not the same in the two morphological variants of the fiddler crab, Uca pugilator. After electrophoresis of hemolymph from the light patch variant of Uca pugilator four hemocyanin components are seen whereas only three components are seen in the hemolymph from the dark patch variant.
50 citations
TL;DR: Fiddler crabs have compound eyes that are structurally fairly well understood, but there has been much debate regarding their spectral sensitivity and capacity to enable colour discrimination, so sensitivity to longer wavelengths enhances contrast between background and the male major claw during the waving display.
Abstract: SUMMARY Fiddler crabs have compound eyes that are structurally fairly well
understood. However, there has been much debate regarding their spectral
sensitivity and capacity to enable colour discrimination. We examined the
visual pigments of two North-American species ( Uca pugnax and U.
pugilator ), one species from the Indo-West Pacific ( U. vomeris )
and the only Eastern-Atlantic species ( U. tangeri ) of fiddler crabs
using in situ microspectrophotometry of frozen sections of
dark-adapted eyes. Only one spectral class of visual receptor was found in the
larger (R1–7) retinular cells of each species, with maximum absorption
peaking between 508 nm and 530 nm (depending upon species). The R8 retinular
cell, that might contain a short-wavelength sensitive photopigment and provide
a basis for colour vision, was too small to analyze by these methods. Rhabdoms
were lined with screening pigment which strongly influenced each species9
spectral sensitivity, sharpening the peak and shifting the maximum towards
longer wavelengths, on occasion to as far as the 600 nm region. We hypothesize
that sensitivity to longer wavelengths enhances contrast between background
(blue sky or tall vegetation) and the male major claw during the waving
display.
50 citations
TL;DR: Six of the animals which had been deprived of their eyestalks laid mature eggs during the course of the experiment; none of the controls did so.
Abstract: 1. Removal of the eyestalks of adult females of Uca pugilator results in a period of rapid ovarian growth in which the increase in fresh weight of the gonad is approximately five-fold in a thirty-day period.2. The period of ovarian growth is characterized by increase in oocyte diameter and a color change from light pink to a deep purple-red.3. Implantation of sinus-gland tissue into the abdomens of destalked females serves to inhibit to a large degree this rapid growth.4. Six of the animals which had been deprived of their eyestalks laid mature eggs during the course of the experiment; none of the controls did so. Eggs produced by the experimental animals failed to become attached to the pleopods.
49 citations
TL;DR: Gonad inhibiting hormone does not induce gonadal inhibition in fiddler crabs, but it does delay the onset of the molt cycle in eyestalkless crabs andMelanin dispersion in intact Uca pugilator was inversely correlated with gonadal growth.
Abstract: The eyestalk neurosecretory system of Crustacea contains several peptide factors affecting various important physiological processes. Gonad inhibiting hormone (GIH) and a molt inhibiting hormone (MIH) have been separated and partially characterized using Sephadex gel chromatography and polyacrylamide gel electrophoresis. The eyestalks of the spiny lobster Panulirus argus were the source for these isolations, and activity was bioassayed in the fiddler crab Uca pugilator. Gonad inhibiting hormone has an apparent molecular weight near 5,000 daltons. Molt inhibiting hormone does not induce gonadal inhibition in fiddler crabs, but it does delay the onset of the molt cycle in eyestalkless crabs. Melanin dispersion in intact Uca pugilator was inversely correlated with gonadal growth.
49 citations