Spatial distribution of the parasite Kroyeria carchariaeglauci Hesse, 1879 (Copepoda: Siphonostomatoida: Kroyeriidae) on gills of the blue shark (Prionace glauca (L., 1758))

Five blue sharks (Prionace glauca) were examined for gill-infesting copepods. Three species of siphonostomatoid copepods were collected: Gangliopus pyriformis, Phyllothyreus cornutus, and Kroyeria carchariaeglauci. The spatial distribution of K. carchariaeglauci was analyzed. The number of K. carchariaeglauci per shark was positively related to gill surface area and host size. Copepods were unevenly distributed amongst hemibranchs; flanking hemibranchs could be arranged into three statistically homogeneous groups. Female K. carchariaeglauci typically attached themselves within the middle 40% of each hemibranch; males were more evenly dispersed. Eighty percent of all K. carchariaeglauci attached themselves to secondary lamellae, the remainder were in the underlying excurrent water channels. Most K. carchariaeglauci were located between 10 and 25 mm along the lengths of gill filaments. Overall, the spatial distribution of K. carchariaeglauci was quite specific in all study planes. Explanation of this distribution is set forth in terms of natural selection pressures; however, the equally plausible explanation that the distribution pattern exhibited by these copepods is phylogenetically determined and may have little to do with contemporary selective constraints should not be ignored.

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Ultrastructure and morphometry of the gills of Latimeria chalumnae , and a comparison with the gills of associated fishes

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1980.0053 ◽

1980 ◽

Vol 208 (1172) ◽

pp. 309-328 ◽

Cited By ~ 18

Keyword(s):

Surface Area ◽

Basic Structure ◽

Phylogenetic Relations ◽

Secondary Lamellae ◽

Grande Comore ◽

Mode Of Life ◽

Gill Filaments ◽

Gill Surface Area ◽

Epithelial Layers ◽

Shallow Water Species

The gross morphology of Latimeria gills is characterized by well developed interbranchial septa that extend almost to the tips of the filaments of each hemibranch and among living fish resembles most closely that of the gills of the lungfish, Neoceratodus . Morphometric studies have shown that Latimeria has a very small gill surface area ( ca . 18 mm 2 /g body mass). The total length of the gill filaments is low and comparable with that of other fishes caught at similar depths (200 m) off Grande Comore. These fish also have smaller gill areas than those of shallow water species collected during the British-French-American expedition. The second gill arches of embryonic and very small Latimeria have a similar number of filaments to those of the adults and regression analysis suggests that filament length increases more gradually with body size in Latimeria than in most other fish, except for some Pacific fish collected from depths of 1300 m. Latimeria gills were examined in the electron microscope and compared with those of Neoceratodus . In both species the basic structure is similar to that of other fishes, having a water-blood barrier consisting of two epithelial layers, a basement membrane and pillar cell flange layers. The outer surface of the epithelium is covered with microvilli and microridges beneath which are a series of bodies reminiscent of those found in elasmo-branch fish. In Latimeria the spaces between the two epithelial layers contained lymphocytes of several types that were similar to those present in the blood channels. As in other fish secondary lamellae, the marginal channels are lined by endothelial cells containing typical osmiophilic granules, but, unlike in Latimeria and all other fish examined, such bodies were also present in the pillar cells of Neoceratodus . The distance between water and red blood cells in Latimeria is greater (6-8 μm) than in most fish and this, together with the low gill surface area, shows that this fish is ill-equipped for high oxygen uptake. A very sluggish mode of life is indicated and excessive exercise would result in hypoxic stress. The gills thus combine features related to the phylogenetic relations of Latimeria with others that it shares with unrelated fish living in similar habitats.

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Respiratory gill surface area of a facultative air-breathing loricariid fish, Rhinelepis strigosa

Canadian Journal of Zoology ◽

10.1139/z94-272 ◽

1994 ◽

Vol 72 (11) ◽

pp. 2009-2015 ◽

Cited By ~ 9

Author(s):

C. T. C. Santos ◽

M. N. Fernandes ◽

W. Severi

Keyword(s):

Surface Area ◽

Body Mass ◽

Gill Filament ◽

B Value ◽

Filament Length ◽

Air Breathing ◽

Rate Of Development ◽

Secondary Lamellae ◽

Gill Filaments ◽

Gill Surface Area

The respiratory surface area of the gill in relation to body mass of the facultative air-breathing loricariid fish Rhinelepis strigosa was analyzed using logarithmic transformation (log Y = log a + b log W) of the equation Y = aWb. The data revealed differences in growth pattern for each gill element. The increase in gill surface area was not isometric with body mass (b = 0.76). The total number of secondary lamellae (b = 0.38) and the average bilateral surface area of the secondary lamellae (b = 0.46) contributed most to the rate of development of the gill surface area (total area of the secondary lamellae) with increase in body mass. Gill filament length (b = 0.339) was more important than the frequency (number/mm) of secondary lamellae in determining the increase in the total number of secondary lamellae. The number of gill filaments showed the lowest b value, 0.072. Rhinelepis strigosa has a larger gill surface area than most other air-breathing fish, indicating that it is better adapted for breathing in water than in air.

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Comparison of Ectoparasite Pathology on Gills of Yellowfin Bream, Acanthopagrus-Australis (Gunther) (Pisces, Sparidae) - a Surface-Area Approach

Australian Journal of Zoology ◽

10.1071/zo9870093 ◽

1987 ◽

Vol 35 (1) ◽

pp. 93 ◽

Cited By ~ 6

Author(s):

FR Roubal

Keyword(s):

Surface Area ◽

Size Range ◽

Unit Length ◽

Gill Filament ◽

Host Size ◽

Filament Length ◽

Large Size ◽

Gill Filaments ◽

Gill Surface Area

The number of gill filaments, length of gill filament and corresponding surface area affected by individual adults of Haliotrerna spariensis (Monogenea) and Ergasilus sp. and individual adults, subadults and larvae of Alella macrotrachelus (Copepoda) are examined in a large size range of the host, Acanthopagrus australis. The effects of these parasites are analysed as proportions of total filament length and total gill surface area. The parasites arranged in order of increasing number of filaments affected are: Ergasilus sp., larval A. macrotrachelus, H. spariensis, subadult A. macrotrachelus and adult A. macrotrachelus. For Ergasilus sp., H. spariensis and larval A. macrotrachelus, the length of filament affected was constant irrespective of host size; adult A. macrotrachelus affect greater lengths of filament in smaller fish, but subadult stages affect greater lengths in larger fish. Possible reasons for this are discussed. The relative pathogenicity is reduced when filament length is converted to surface area. This reduction is greater in smaller fish because they have a smaller surface area per unit length of filament than larger fish.

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Gill Surface-Area and Its Components in the Yellowfin Bream, Acanthopagrus-Australis (Gunther) (Pisces, Sparidae)

Australian Journal of Zoology ◽

10.1071/zo9870025 ◽

1987 ◽

Vol 35 (1) ◽

pp. 25 ◽

Cited By ~ 6

Author(s):

FR Roubal

Keyword(s):

Surface Area ◽

Gill Filament ◽

Weighting Factor ◽

Head Length ◽

Regression Equations ◽

Middle Zone ◽

Filament Length ◽

Basal Zone ◽

Gill Filaments ◽

Gill Surface Area

As head length (HL) of Acanthopagrus australis increases, fewer gill filaments are added, total gill filament length (TFL) increases linearly, and total gill surface area (TSA) increases exponentially. Changes in surface area components [surface area per lamella (SA), distance between adjacent lamellae (DBT) and number of lamellae per zone on one side of the filament (NPZ)] with increasing HL were examined in the distal, middle and basal zones (relative lengths 3:10:1) of a corresponding filament on the external hemibranch of the four gill arches. SA was the smallest in the basal zone and largest in the middle zone; DBT was greatest in the distal zone and smallest in the basal zone; SA and DBT increased at similar rates in different gill arches within the distal and middle zones but at different rates in each zone within an arch; growth of NPZ in the middle zone differed among gill arches but did not in the distal zone. Surface area of lamellae in the middle zone contributed most to increasing TSA. Compared with other fish of intermediate activity, the estimate of TSA for A. australis was smaller than expected; although DBT and TFL were as expected, SA was smaller than expected; possible reasons include method of measurement in situ, shrinkage caused by fixation, and absence of a weighting factor. The method employed enables large numbers of lamellae and filaments in a large number of fish to be measured, and enables regression equations to be derived that relate surface area per filament zone to head length and filament length in order to estimate the loss of surface area caused by ectoparasites.

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