The evolution of the Haustorioidea of the world, and post-embryonic development, taxonomy and ecology of the Haustoriidae (Amphipoda-Crustacea) /

The Haustorioidea is proposed to be a monophyletic taxon

Bibliographic Details
Main Author: Sweet, Merrill Henry, 1961-
Format: Thesis Book
Language:English
Published: [Place of publication not identified] : [publisher not identified] ; 1996.
Subjects:
Online Access:http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=739668001&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD
Description
Summary:The Haustorioidea is proposed to be a monophyletic taxon
evolving from the pontocaspian gammarids. A straight-line
derivation through hypothesized intermediates was determined
for Platyischnopidae, Phoxocephalidae and Urothoidae. An
hypothesized urothoid-like ancestor gave rise to a
haustoriid-condukiid and phoxocephalopsid-zobrachoid-
urohaustoriid lineages. The hypothesized line of descent for
the genera of Haustoriidae are (from most plesiomorphic to
apomorphic): Protohaustorius, Neohaustorius, Parahaustorius,
Lepidactylus and another ancestor, which independently
evolved into an acanthohaustorius (Acanthohaustorius,
Pseudohaustorius and Eohaustorius) and haustorius group of
genera. The haustorius group evolved into Haustorius
(arenarius and algeriensis), Genus one (canadensis), Genus
two and Genus three. The latter new genera are from the Gulf
of Mexico. Phylogenetic, evolutionary and phenetic results
are compared using the same data base. Only the phenetic
analysis gave nonevolutionary results. Also, an area
cladograrn for the Haustorioidea and a habitat cladogram for
the Haustoriidae is presented. The primary events impacting
the vicariance of the Haustoriidae include a subtidal
migration in the Late Mesozoic, a separation of particular
taxa by the Euramerican land mass in the Late Cretaceous and
the opening of the Suwanne Seaway in the Miocene. A method
using the merus of pereopod 7 is presented for aging
haustoriid amphipods. A "twin peak" monthly size-frequency
pattern was observed, and Gulf haustoriids evidently molt
either at new or full moon once a lunar month. Furthermore,
development is deterministic with seven juvenile stages and
two adult stages. The characteristics are given for the
stages of each species examined. A key and diagnoses are
presented for species of haustoriid amphipods of the Atlantic
Ocean and Gulf of Mexico. In addition, included are
descriptions of three newly erected genera and eleven new
species from the Gulf. Ecologically, less contagious sampling
results were obtained by elevation sampling; haustoriid
amphipods and S. squamata partition the beach by age and
species, and are strongly impacted by enhanced sediment size
and vehicular traffic; and Genus two species c partitions the
beach by sex. It appears from a demographic study that Genus
two species c has juvenile stages which migrate from the
beach in the summer and winter, and a type IV survivorship
curve.
Item Description:Vita.
"Major Subject: Zoology".
Physical Description:3 volumes (xxxvii-640 leaves) : illustrations ; 28 cm.
Issued also on microfiche from University Microfilms Inc.
Bibliography:Includes bibliographical references: pages 455-472.