Browsing by Author "Eardley, Connal Desmond."

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Investigating floral choice in bees (megachilidae) using pollen metabarcoding.
(2017) Gous, Annemarie.; Willows-Munro, Sandi.; Swanevelder, Dirk Z.H.; Eardley, Connal Desmond.
Interactions between plants and their pollinators are often poorly understood, specifically in a species-diverse country such as South Africa. Traditional methods of studying plant-pollinator interactions are time-consuming and imprecise. This study aimed to develop a technique that uses genetic analyses to identify pollen provenance directly from bees (Megachilidae) housed in a historic collection and to apply this technique to investigate floral choice differences in species of megachilid bees from three regionally important areas in South Africa: the Succulent Karoo, Savanna, and a widespread group, with bees occurring throughout the country. To develop the technique to accurately identify provenance, pollen was sampled from Megachile venusta specimens in the collection. Three DNA barcode regions were amplified and sequenced on an Illumina MiSeq instrument: the internal transcribed spacer 1 (ITS1) and internal transcribed spacer 2 (ITS2) regions, and the ribulose-1,5-biphosphate carboxylase (rbcL) gene. Sequenced reads were compared to sequence reference databases that were generated by extracting sequence and taxonomic data from GenBank. ITS2 reads were also compared to an established ITS2 database for Viridiplantae. More diverse plant classifications were obtained with ITS2 compared to ITS1. Amplification and sequencing of rbcL was inconsistent on pollen sampled from historic specimens. To study how floral choice differed in three South African regions, ITS2 was sequenced on Illumina HiSeq and MiSeq from pollen sampled from two different bee species from each region. Sequence reads were compared to the previously published ITS2 sequence reference database. Generalised linear models (GLM) indicated that the mean number of both plant families and species varied significantly between bee species. No significant effect of the time since bee collection was found. Taxon identifications were only confidently interpreted on family-level due to very limited local plant representation in sequence reference databases. DNA metabarcoding of mixed-origin pollen samples provided a faster, more accurate method of determining pollen provenance, without the need for expert palynologists. The use of historic collections to sample pollen directly from pollinators provided additional value to these collections. Sampling pollen from historic collections can also provide the spatial and temporal scales for investigations into changes in plant community structure or pollinator floral choice in the face of global climate change.
Phylogeny of the Ammobatini and revision of the Afrotropical genera (Hymenoptera : Anthophoridae : Nomadinae)
(1994) Eardley, Connal Desmond.; Brothers, Denis John.
The phylogeny of the Ammobatini was studied, with regard to the principles of cladistics using parsimony, and the classification is revised. It is concluded that the tribe forms a monophyletic group that comprises six distinct monophyletic genera: Pasite Jurine, Sphecodopsis Bischoff, Ammobates Latreille, Melanempis Saussure, Spinopasites Warncke and Oreopasites Cockerell, of which Pasites, Sphecodopsis, Ammobates and Melanempis occur in the Afrotropical Region. The Afrotropical species of these four genera are revised. Pseudopasites Bischoff and Pseudodichroa Bischoff are synonymized with Sphecodopsis. Pasites includes 17 Afrotropical species, Sphecodopsis 10 species, and Ammobates and Melanempis are each known from a single Afrotropical species. Ten new species are described: Passites nilssoni, P. paulyi, P. humecta, P. gnoma, P. namibiensis, P. somalica, Sphecodopsis vespericena, S. longipygidium, S. namaquensis and Ammobates auster. Thirty-three names are synonymized: they are P. nigerrima (Friese), P. argentata (Baker) (= P. barkeri (Cockerell)); P. chubbi Cockerell, P. nigritula Bischoff, P. peratra Cockerell (= P. atra Friese); P. nigripes (Friese), P. fortis Cockerell, P. subfortis Cockerell, P. stordyi Cockerell, P. voiensis Cockerell, P. altior Cockerell (= P. carnifex (Gerstaecker)); P. natalensis (Cockerell), P. aiboguttatus (Friese), P. ogilviei (Cockerell) (= P. jenseni (Friese)); P. alivalensis (Cockerell), P. rufitarsis (Cockerell) (= P. histrio (Gerstaecker)); P. marshaUi (Cockerell) (= P. jonesi (Cockerell)); P. abessinica (Friese), P. fulviventris (Bischoff), P. rhodesialla (Bischoff), P. apicalis (Bischoff), P. turneri (Cockerell), P.politula (Cockerell), P. indecisa (Cockerell), P. nudicauda (Cockerell), P. bechuanica (Cockerell), P. breviceps (Cockerell) (= P. appletoni (Cockerell); S. rufula (Cockerell) (= S. minutissima (Cockerell)); S. pygmaea (Friese), S. rufescens Bischoff, S. algoensis Bischoff, S. perpunctata Cockerell (= S. aculeata (Friese)); S. leonis (Cockerell) (= S. semirufa (Cockerell)). Keys to the genera and species are provided.
The taxonomy and systematics of the bee genus Scrapter (Colletidae: Colletinae: Scraptrini)
(2016) Mthethwa, Qiniso Michael.; Willows-Munro, Sandi.; Eardley, Connal Desmond.
Scrapter is a southern African endemic pollen-collecting genus consisting of 43 described species with 13 species also occurring in neighbouring countries such as Lesotho, Mozambique, Namibia and Zimbabwe. Classification of Scrapter has been partially investigated using only morphological data set. In this study I reassess previous classification and describe a putative new species which has never been described before, Scrapter leovalis sp. nov. This study aimed at reassessing previous classification of Scrapter using 46 morphological characters and provide a new classification based molecular data; 28SrRNA, EF-1α and Opsin gene. Using phylogenetic methods such as parsimony analysis, maximum likelihood and bayesian analysis classification of Scrapter was possible. However, analyses of morphological characters only did not produce reliable phylogenies due to low branch supports (bootstrap and posterior support). Molecular data was analyzed individually and in supermatrix analyses which produced phylogenetic trees with high branch supports. To see how the morphological and molecular data complemented each other a simultaneous analysis of 28SrRNA EF-1α, Opsin and morphological characters was carried out. Simultaneous analysis produced phylogenetic trees resembling supermatrix trees obtained in the simultaneous analysis of the three genes alone. It was then concluded that morphological characters chosen for this study were not phylogenetically informative.