Ichthyology

Whalefishes (Beryciformes: Cetomimoidei) of the Gulf of Mexico

by Greg Tolley

Seven species of whale fishes, belonging to three families, were collected by assorted research vessels from various... more Seven species of whale fishes, belonging to three families, were collected by assorted research vessels from various locations within the Gulf of Mexico from 1965 through 1987. This material, which includes two species new to the region, raises the recorded number of cetomimoid species in the Gulf to eight. A significant positive correlation was found between size and maximum depth of capture for all Gulf specimens of Cetostoma regani (r = 0.84, P < 0.02, N = 7), indicating the possibility of ontogenetic descent for this species. Gulf of Mexico whalefishes exhibit broad horizontal distribution patterns common among bathypelagic fishes. The relatively high species richness exhibited by cetomimoid fishes in the Gulf appears to be characteristic of midwater fish assemblages associated with low latitude, oligotrophic environments.

First record of the family Caristiidae (Osteichthyes) from the Gulf of Mexico

by Greg Tolley

1990 Northeast Gulf Science 11:159-162

The occurrence of Gunterichthys longipenis (Osteichthyes: Bythitidae) in a southwest Florida estuary

by Greg Tolley

1987 Northeast Gulf Science 9:43-47

Distribution, growth and mortality of larval spotted seatrout, Cynoscion nebulosus: A comparison between two adjacent estuarine areas of southwest Florida

by Greg Tolley

Distribution, growth, and mortality of larval spotted seatrout, Cynoscion nebulosus, were compared between the Naples... more Distribution, growth, and mortality of larval spotted seatrout, Cynoscion nebulosus, were compared between the Naples Bay and Fakahatchee Bay areas of southwest em Florida during the period of July 1983 through January 1985. Back-calculated spawning dates ranged from mid-March through mid-October, with major peaks occurring during the warmer months. Monthly larval densities were positively correlated with water temperature in Naples Bay (r = 0.35, P < 0.01). Cumulative larval lengths were significantly smaller (P < 0.001) in Naples Bay, suggesting a greater proximity of collection stations to spawning locations in this area. Station-specific length distributions indicated that spawning probably occurred in the lower part of Naples Bay and in shallow Gulf of Mexico waters near the Fakahatchee study area. Salinity and temperature are discussed as determinants of spawning activity and larval distribution. A growth rate of approximately 0.4 mm/d was found for both areas. The apparent instantaneous daily mortality coefficient was significantly larger for Naples Bay (0.64 vs. 0.36, P < 0.001).

Occurrence of larval snook, Centropomus undecimalis (Bloch), in Naples Bay, Florida

by Greg Tolley

An extensive ichthyoplankton sampling program was conducted in Naples Bay, Florida during the period of June 1983 to... more An extensive ichthyoplankton sampling program was conducted in Naples Bay, Florida during the period of June 1983 to January 1985. Fourteen larval snook, Centropomus undecimalis, were collected during the course of sampling. Larvae ranged from 4.4-7.0 mm standard length and all exhibited complete notochord flexion. All larvae were taken during two 24 h periods in July of 1983 and 1984. Snook larvae were collected on a flood tide within five days fo a full moon, and 86% were associated with the bottom. A significant relationships was found between larval size and the salinity of capture (r = -0.67, P = 0.01, N = 13), indicating the occurrence of larger larvae in waters of lower salinity. the Centropomus larvae collected did not comprise of the ichthyoplankton of the area, contributing less than 0.05% to the total number of fish larvae taken from Naples Bay.

Association of young Chloroscombrus chrysurus (Pisces: Carangidae) with the jellyfish Aurelia aurita

by Greg Tolley

Egg production by the bay anchovy (Anchoa mitchilli) in relation to adult and larval prey fields

by Greg Tolley

Abundances of copepod nauplii, copepodite/adult copepods, and the larvae of iteroparous anchovies (primarily the bay... more Abundances of copepod nauplii, copepodite/adult copepods, and the larvae of iteroparous anchovies (primarily the bay anchovy Anchoa mltchllli) were monitored in Tampa Bay, Florida (USA) at 2 wk intervals for 2 yr. All possible pairings of the 3 time-series variables yielded significant positive correlations. Nearly all (>98%) of the collected anchovy larvae occurred with prey (nauplius) densities higher than those reported to affect larval starvation (<l00 l-1). The larval association with abundant prey could be explained as (1) the remnants of earlier larval starvation, or (2) spawning being concentrated in zooplankton-rich waters. To evaluate the 2 explanations, the diet of adult A. mitchilli was analyzed, and egg/adult prey surveys were conducted across a 290 km2 area of Tampa Bay. In 5 of the 6 spatial surveys. A. mitchilli egg abundance was correlated with the abundance of calanoid copepods, a principal adult prey item. Calanoids (primarily adult Acartia tonsa) were never correlated with net plankton biomass or with the eggs of the bay anchovy's congener, Anchoa hepsetus. Calanoids were aggregated near sites of stable freshwater discharge during a dry season, but became dispersed as discharge increased during a rainy season. Among spatial surveys, egg abundance exhibited a strong nonlinear relationship with calanoid aygregatlon (r2 = 0.96, n = 6, p = 0.001) Collectively, these findlngs suggest that the bay anchovy's size-specific fecundity is related to adult prey availability, with adult prey auakiablty being represented by a combination of abundance and patchiness. We discuss relationships between spawning pattern and environmental instability, and suggest that iteroparity serves to fine-tune reproductive effort to environmental parameters that are relevant to larval survival.

Decay of diel patterns of swimming activity in juvenile common snook (Centropomus undecimalis) maintained in captivity

by Greg Tolley

Energetics of swimming in juvenile common snook , Centropomus undecimalis

by Greg Tolley

Little research has been devoted to the investigation of swimming energetics and performance in lie-in-wait predators.... more Little research has been devoted to the investigation of swimming energetics and performance in lie-in-wait predators. This study evaluated activity metabolism and swimming performance in juvenile snook, Centropomus undecimalis, a lie-in-wait predator, by determining oxygen uptake in a tunnel respirometer. Compared to previously reported results for more actively foraging species (i.e., white crappie, rainbow trout), snook exhibited lower maintenance metabolism (58.6 ml O-2 kg(-1) WM h(-1)) and greater metabolic expansibility (6.5). Relative critical swimming speeds decreased isometrically with length, implying that small snook are capable of prolonged swimming in velocity regimes similar to those experienced by larger individuals. Swimming was most efficient at the transition between pectoral (low-speed) and caudal (high-speed) propulsion. The results of this study support previous speculation that maintenance costs may be reduced in lie-in-wait predators compared to other fishes.

Levantamento da ictiofauna da Floresta Nacional de Canela, na região superior da bacia hidrográfica do Rio Caí, Rio Grande do Sul, Brasil

by Ismael Franz

Development of the olfactory system in turbot (Psetta maxima L.)

by Leonardo Mantilla Aldana

published in: Journal of Chemical Neuroanatomy
Volume 41, Issue 3, April 2011, Pages 148-157

We have examined the histogenesis of the olfactory system during turbot development using histological and... more We have examined the histogenesis of the olfactory system during turbot development using histological and immunohistochemical methods. Proliferating cell nuclear antigen (PCNA) immunohistochemistry was used to detect dividing cells, whereas calretinin (CR) immunohistochemistry was used to distinguish some neuronal components of the olfactory system. Around hatching, the olfactory placode of embryos transforms into an olfactory pit, which enlarges progressively during development. In metamorphic turbots, the right olfactory organ moves to the tip of the head. Each olfactory chamber opens to the external medium by two nostrils and accessory nasal sacs develop during metamorphosis. The order of birth of olfactory receptor cells in the sensory epithelium follows the pattern of most teleosts: ciliated cells differentiate prior to microvillous cells in turbot larvae, and crypt cells are generated during metamorphosis. Axons of olfactory sensory neurons reach the rostral forebrain by hatching, and calretinin-immunoreactive (CR-ir) glomerular fields were apparent during the subsequent larval development. During metamorphosis olfactory bulbs become strongly distorted by head torsion and glomeruli acquire asymmetric organization. The spatio-temporal course of proliferation in the olfactory system reveals changes in the distribution of dividing cells in the sensory epithelium throughout the developmental period investigated. In the olfactory bulb, proliferative activity becomes restricted to the ventral periventricular zone in turbot larvae, as well as in metamorphic specimens.

MORFOLOGIA COMPARATIVA DE LAS CELULAS SANGUINEAS DEL TIBURON NODRIZA Ginglymostoma cirratum (Bonnaterre, 1788) CON DIVERSOS PECES

by Leonardo Mantilla Aldana

Dahlia (1996) 1: 97-102

This work is a comparation of the blood cells morphology between 9 nurse sharks, southern stingray and 9 bone fishes,... more This work is a comparation of the blood cells morphology between 9 nurse sharks, southern stingray and 9 bone fishes, moreover, it was maked a differential leucocytes count, red and white cells counts by blood mm3 for any fish.

First record of the white-eye goby, Bollmannia boqueronensis (Teleostei: Perciformes: Gobiidae) along the coast of the Yucatan Peninsula (Gulf of Mexico)

by Rigoberto Moreno-Mendoza

Authors: Moreno-Mendoza, R; González-Salas, C.; Gallardo-Torres, A & Simoes, Nuno.
Year: 2011
Published in Marine Biodiversity Records

Bollmannia boqueronensis is a tropical marine goby. Two specimens were captured at 25 m depth on the Alacranes Reef,... more Bollmannia boqueronensis is a tropical marine goby. Two specimens were captured at 25 m depth on the Alacranes Reef, Mexico, off the north-east coast of the Yucatan Peninsula (Gulf of Mexico) in August 2009. The present note extends the known distribution area of this species towards the west and constitutes the first record for Mexico.

Quaternary palaeoenvironmental oscillations drove the evolution of East Asian Carassius auratus complex (Carassius, Cypriniformes, Cyprinidae)

by Robert Murphy

Gao, Y., S.-Y. Wan, J. Luo, R.W. Murphy, R. Du, S.-F. Wu, C.-L. Zhu, Y. Li, A. D. Poyarkov, S. N. Nguyen, P.-T. Luan, and Y.-P. Zhang. In press. Quaternary palaeoenvironmental oscillations drove the evolution of East Asian Carassius auratus complex (Carassius, Cypriniformes, Cyprinidae). Journal of Biogeography. (JBI-11-0396R1).

Morphology, characters, and the interrelationships of basal sarcopterygians

by Richard Cloutier

Authors: Cloutier, R. & P.E. Ahlberg
Year:1996
Reference: Pp. 445–479.  In M.L.J. Stiassny, L.R. Parenti & G.D. Johnson (eds.) Interrelationships of Fishes.  Academic Press, New York

End-Devonian extinction and a bottleneck in the early evolution of modern jawed vertebrates

by Lauren Sallan

Heads or tails: staged diversification in vertebrate evolutionary radiations

by Lauren Sallan

Persistent predator–prey dynamics revealed by mass extinction

by Lauren Sallan

Growth, body morphology and muscle metabolism patterns in newly-hatched salmonid species (S. alpinus and O. mykiss): effects of water velocity

by Richard Cloutier

Authors: Le François, N., T. Grünbaum, K. Chu, A. Savoie & R. Cloutier
Year: 2006
Reference: Bull. Aquacul. Assoc. Canada: 106-3: 33-36

Increased growth rate at higher water velocities is commonly observed in salmonids. The improvement in swimming... more Increased growth rate at higher water velocities is commonly observed in salmonids. The improvement in swimming performance (maximum sustainable speed, rates of recovery, endurance), however, remains poorly documented. We propose to use indicators of enhanced swimming performance and muscular growth of newly-hatched Arctic charr and rainbow
trout, two species with different degrees of polymorphism. The impact of water velocity on body morphology, growth, and temporal changes in white muscle metabolic capacities (citrate synthase, lactate dehydrogenase, and nucleoside diphosphokinase) were measured. Newly-hatched fish were reared for 100 days at four water velocities: A = 3.2 cm/s, B = 1.6 cm/s, C = 0.8 cm/s, and D = 0.4 cm/s. At the end of the growth trial on Arctic charr, the velocity treatments were reversed (i.e., high velocity (HV) fish were transferred to the low velocity (LV) rearing units and vice versa) and adjustments in enzyme activity level of LDH, CS, and NDPK were monitored for 67 days. Preliminary results show that the high velocity treatment had a more pronounced impact on the growth rate of Arctic charr than on rainbow trout. We suggest that adjustments in muscular energy metabolism and muscle synthesis should be observable and positively related to water velocity.

Congruence between chondrification and ossification sequences during caudal skeleton development: a Moxostomatini case study

by Richard Cloutier

Authors: Grünbaum, T., R. Cloutier & P. Dumont
Year: 2003
Reference: Pp. 161-176.  The Big Fish Bang.  Proceedings of the 26th Annual Larval Fish Conference (H.I. Browman & A.F. Skivtesvik, eds.)

Ontogeny can be studied either in terms of size and shape changes (i.e., traditional view of heterochrony) or... more Ontogeny can be studied either in terms of size and shape changes (i.e., traditional view of heterochrony) or developmental sequences. However, only a few studies have focused on the caudal skeleton of catostomid species and its developmental sequence value in systematics especially among closely related taxa. The early ontogenetic development of the caudal skeleton of the endangered catostomid copper redhorse (Moxostoma hubbsi, Ostariophysii, Moxostomatini) endemic to south eastern Canada and two closely related sympatric species, M. anisurum and M. macrolepidotum, was studied with cleared and double stained specimens. This study provides the first morphological description of the caudal skeleton of M. hubbsi as well as its developmental sequences (i.e., chondrification and ossification sequences). Congruence between chondrification and ossification sequences is tested intraspecifically and interspecifically for the three Moxostoma species. Intraspecific comparisons exhibit a weak congruence between both sequences for each Moxostoma species. There is a strong interspecific congruence among chondrification sequences and among ossification sequences. Phylogenetic and functional constraints might be responsible for the canalization of the chondrification and ossification sequences. Because of the weak intraspecific congruence between the two developmental sequences we suggest that further developmental studies integrate data derived from chondrification and ossification sequences. Acquisition of such ontogenetic data is of great significance in understanding how ontogeny and phylogeny
interact to create morphological diversity.