Banca de DEFESA: ROSA DA SILVA SANTOS

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : ROSA DA SILVA SANTOS
DATA : 28/08/2019
HORA: 14:00
LOCAL: Sala 34 do icbs
TÍTULO:

Ecomorphological patterns in fish from a tropical bay in southeastern Brazil: approaches using shape of the sagittae otoliths, body shape and diet.

PALAVRAS-CHAVES:

coastal fish, otoliths, diet, morphology, Sepetiba Bay.

PÁGINAS: 139
GRANDE ÁREA: Ciências Biológicas
ÁREA: Ecologia
SUBÁREA: Ecologia Aplicada
RESUMO:

Ecomorphology in fish is the study of the relationships between individuals' body shape
and their ecological function, based on the comparison between patterns of variation in
shape and patterns of variation of morphological attributes such as feeding habits and
niche exploration. Based on this principle, we sought to identify the ecomorphological
patterns related to the shape of the sagittae otoliths, body shape, and diet of species that
make up the fish assemblage of a tropical bay in southeastern Brazil.The ichthyofauna
sampled came from the shrimp trawling, and was dominated by small-sized individuals
(subadults) and comprised 22 species. In the Second Chapter, the cluster analysis on the
contour data of the otoliths (Fourier Ellipses Analysis - EFA) resulted in the
identification of 9 groups. The different otoliths patterns indicate different functions,
from the longer and wider otoliths (associated with greater auditory capacity with
botton foraging) to smaller and narrower otoliths with prominent rostra (associated with
greater swimming capacity and less need for acoustic communication). A significant
correlation was found between the size of the otoliths in relation to the size of the fish
for benthic species and that they have large otoliths (M. furnieri, P. brasiliensis and O.
ruber). For the other species, the size of the otolith did not present consistent change as
function of the size of the individuals that are mostly juveniles. In the Third Chapter, 17
morphometric measurements were taken for the calculation of 10 ecomorphological
attributes, which were used to interpret the life habits and a better understanding of the
adaptations and occupation of different habitat use. The Principal Components Analysis
applied to the ecomorphological attributes allowed the identification of eight groups of
fish. The ecomorphological attributes that most influenced the division of the groups
were compression index (CI), caudal peduncle compression index (ICPCd), relative
height (RA), relative eye position (PRO) and relative head length (CRC). Therefore, the
fish that most differed in this analyses were the Pleuronectiformes (with high bodies
laterally compressed, indicating to be able to vertical displacements with limited
maneuverability) and the Scorpaeniformes (with eyes positioned dorsally and with a
relatively long head indicating benthic habits capable of catching relatively large prey),
suggesting different ways to explore the environment.In the Fourth Chapter, through the
bibliographic survey based on secondary data, it can be concluded that the great
majority of the species studied are carnivorous ichthyophagous (13 species), of which
some practice cannibalism. It was noticiable the use of crustaceans (Decapoda,
Brachyura, Mysidacea), annelids (Polychaeta, Nereidae) and molluscs (Gastropoda,
Bivalvia, Cephalopoda) as food items of almost all species, with the exception of
Engraulidae Cetengraulis edentulus which was the only exclusively herbivorous species
preying on phytoplankton components.This species was isolated from the others in the
three approaches, presenting high values of ARB, ABO and CRPCd, as well as
differentiated otoliths with prominent rostra, dented ventral border and quite different
feeding habits. These characteristics constrain this species to remain in an isolated
group in the three approaches. Gerreidae Eucinostomus gula and Eucinostomus
argenteus presented consistent similarity in both body morphology, otolith morphology
and feeding habits. This consistent similarity was also found for Menticirrhus
americanus and Paralonchurus brasiliensis, which also remained grouped together in
all three approaches.The Pleuronectiformes did not form a consistent group in the 16different approaches, but were always organized in neighboring groups demonstrating acertain level of similarity between them, depending on the level of cut of thedendograms. Cathorops spixii was not used in the otolith morphology approach, but itremained with Orthopristis ruber in the chapters on body morphology and diet. The Sciaenidae stayed together in the body ecomorphology approach (except S. rastrifer) and separated in the ecomorphology approaches of the otoliths and diet, maintainingproximity forming neighboring groups in the dendrograms of the different analyzes. The results demonstrated the existence of an association between body morphology and otoliths, and the life and exploitation habits of resources, particularly those related to food.

MEMBROS DA BANCA:
Externo à Instituição - ALEJANDRA VANINA VOLPEDO
Externo à Instituição - CARLOS ANTÓNIO DA SILVA ASSIS
Interno - 387200 - FRANCISCO GERSON ARAUJO
Interno - 1728466 - JAYME MAGALHAES SANTANGELO
Externo à Instituição - LILIAN CASATTI - UNESP