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Description
Weevils are one of the most diverse groups of animals with thousands of species suspected to remain undiscovered. The Conoderinae Schoenherr, 1833 are no exception, being especially diverse and unknown in the Neotropics where they are recognizable for their unique behaviors and color patterns among weevils. Despite these peculiarities, the group has received little attention from researchers in the past century, with almost nothing known about their evolution. This dissertation presents a series of three studies that begin to elucidate the evolutionary history of these bizarre and fascinating weevils, commencing with an overview of their biology and classificatory history (Chapter 1).
Chapter 2 presents the first formal cladistic analysis on the group to redefine the New World tribes Lechriopini Lacordaire, 1865 and Zygopini, Lacordaire, 1865. An analysis of 75 taxa (65 ingroup) with 75 morphological characters yielded six equally parsimonious trees and synapomorphies that are used to reconstitute the tribes, resulting in the transfer of sixteen genera from the Zygopini to the Lechriopini and four generic transfers out of the Lechriopini to elsewhere in the Conoderinae.
Chapter 3 constitutes a taxonomic revision of the genus Trichodocerus Chevrolat, 1879, the sole genus in the tribe Trichodocerini Champion, 1906, which has had an uncertain phylogenetic placement in the Curculionidae but has most recently been treated in the Conoderinae. In addition to redescriptions of the three previously described species placed in the genus, twenty-four species are newly described and an identification key is provided for all recognized species groups and species.
Chapter 4 quantitatively tests the similarity in color pattern among species hypothesized to belong to several different mimicry complexes. The patterns of 160 species of conoderine weevils were evaluated for 15 categorical and continuous characters. Non-metric multidimensional scaling (NMDS) is used to visualize similarity by the proximity of individual species and clusters of species assigned to a mimicry complex in ordination space with clusters being statistically tested using permutational multivariate analysis of variance (PERMANOVA).
Chapter 2 presents the first formal cladistic analysis on the group to redefine the New World tribes Lechriopini Lacordaire, 1865 and Zygopini, Lacordaire, 1865. An analysis of 75 taxa (65 ingroup) with 75 morphological characters yielded six equally parsimonious trees and synapomorphies that are used to reconstitute the tribes, resulting in the transfer of sixteen genera from the Zygopini to the Lechriopini and four generic transfers out of the Lechriopini to elsewhere in the Conoderinae.
Chapter 3 constitutes a taxonomic revision of the genus Trichodocerus Chevrolat, 1879, the sole genus in the tribe Trichodocerini Champion, 1906, which has had an uncertain phylogenetic placement in the Curculionidae but has most recently been treated in the Conoderinae. In addition to redescriptions of the three previously described species placed in the genus, twenty-four species are newly described and an identification key is provided for all recognized species groups and species.
Chapter 4 quantitatively tests the similarity in color pattern among species hypothesized to belong to several different mimicry complexes. The patterns of 160 species of conoderine weevils were evaluated for 15 categorical and continuous characters. Non-metric multidimensional scaling (NMDS) is used to visualize similarity by the proximity of individual species and clusters of species assigned to a mimicry complex in ordination space with clusters being statistically tested using permutational multivariate analysis of variance (PERMANOVA).
ContributorsAnzaldo, Salvatore (Author) / Franz, Nico (Thesis advisor) / Martins, Emilia (Committee member) / Rabeling, Christian (Committee member) / Pigg, Kathleen (Committee member) / Arizona State University (Publisher)
Created2019
Description
In many social groups, reproduction is shared between group members, whocompete for position in the social hierarchy for reproductive dominance. This
reproductive conflict can lead to different means of enforcing reproductive differences,
such as dominance displays or limited control of social hierarchy through antagonistic
encounters. In eusocial insects, archetypal colonies contain a single, singly-mated fertile
queen, such that no reproductive conflict exists within a colony. However, many eusocial
insects deviate from this archetype and have multiply-mated queens (polyandry), multiple
queens in a single colony (polygyny), or both. In these cases, reproductive conflict exists
between the matrilines and patrilines represented in a colony, specifically over the
production of sexual offspring. A possible outcome of reproductive conflict may be the
emergence of cheating lineages, which favor the production of sexual offspring, taking
advantage of the worker force produced by nestmate queens and/or patrilines. In extreme
examples, inquiline social parasites may be an evolutionary consequence of reproductive
conflict between nestmate queens. Inquiline social parasitism is a type of social
parasitism that is usually defined by a partial or total loss of the worker caste, and the
“infiltration” of host colonies to take advantage of the host worker force for reproduction.
It has been hypothesized that these inquiline social parasites evolve through the
speciation of cheating queen lineages from within their incipient host species. This “intra-
specific” origin model involves a foundational hypothesis that the common ancestor of
host and parasite (and thus, putatively, the host at the time of speciation) should be
functionally polygynous, and that parasitism evolves as a “resolution” of reproductive
conflict in colonies. In this dissertation, I investigate the hypothesized role of polygyny in the evolution of inquiline social parasites. I use molecular ecology and statistical
approaches to validate the role of polygyny in the evolution of some inquiline social
parasites. I further discuss potential mechanisms for the evolution and speciation of social
parasites, and discuss future directions to elucidate these mechanisms.
ContributorsDahan, Romain Arvid (Author) / Rabeling, Christian (Thesis advisor) / Amdam, Gro V (Committee member) / Fewell, Jennifer H (Committee member) / Pratt, Stephen C (Committee member) / Rüppell, Olav (Committee member) / Arizona State University (Publisher)
Created2021