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Debevec, AH., Cardinal, S & Danforth, BN. Identifying the sister group to the bees: a molecular phylogeny of Aculeata with an emphasis on the superfamily Apoidea. - Zoologica Scripta, 41, 527-535. The hymenopteran superfamily Apoidea includes the bees (Anthophila) as well as four predatory wasp families (Heterogynaidae, Ampulicidae, Sphecidae and Crabronidae) collectively referred to as the 'sphecoid' or 'apoid' wasps. The most widely cited studies suggest that bees are sister to the wasp family Crabronidae, but alternative hypotheses have been proposed based on both morphological and molecular data. We combined DNA sequence data from previously published studies and newly generated data for four nuclear genes (28S, long-wavelength rhodopsin, elongation factor-1α and wingless) to identify the likely sister group to the bees. Analysis of our four-gene data set by maximum likelihood and Bayesian methods indicates that bees most likely arise from within a paraphyletic Crabronidae. Possible sister groups to the bees include Philanthinae, Pemphredoninae or Philanthinae + Pemphredoninae. We used Bayesian methods to explore the robustness of our results. Bayes Factor tests strongly rejected the hypotheses of crabronid monophyly as well as placement of Heterogynaidae within Crabronidae. Our results were also stable to alternative rootings of the bees. These findings provide additional support for the hypothesis that bees arise from within Crabronidae, rather than being sister to Crabronidae, thus altering our understanding of bee ancestry and evolutionary history. [ABSTRACT FROM AUTHOR]

We use a relatively densely sampled phylogeny to obtain preliminary estimates for the ages of the major clades identified in Euphorbia, with which we show that the succulent species of Euphorbia have diversified over the last 36 million years into many of the semi-arid, tropical parts of the world. Many major clades have subclades from widely separated regions, often on different continents. Our results imply that these distributions arose by long-distance dispersal after the break-up of Gondwana. In the case of Indian/South-east Asian succulents there appears to have been a single, relatively recent dispersal event from Africa. We have included many species from the Arabian Peninsula and Socotra and we show that these are nested within other, mainly African clades. In some cases Arabian and Socotran taxa have their closest relatives in adjacent parts of North-east Africa and most often this is true in recent clades, while in more ancient clades their closest relatives may be in Macaronesia or in the Namib Desert of Southern Africa so that these are typical 'Rand Flora' elements. In one case, closest known relatives are in North America. We find that Socotran taxa vary between 16 and 3 Ma old. The major diversifications of succulents in temperate Southern Africa (the crown clades in subg. Rhizanthium and more minor clades in subg. Chamaesyce) and in tropical East Africa (the crown clades in subg. Euphorbia) occurred in the last 20-3 Ma. In the Greater Cape Flora of the western part of Southern Africa the diversity in Euphorbia is mainly derived from one lineage in subg. Rhizanthium and one in subg.Chamaesyce. In contrast the diversity ofEuphorbia in the Arabian Peninsula is derived from the invasion (mainly from Africa) of many separate lineages. We show that large, succulent trees are only found in subg. Euphorbia and only occur in the Old World. Most of them fall within a single clade and have evolved relatively recently. [ABSTRACT FROM AUTHOR]

Ifloga and Trichogyne constitute a small but biologically interesting lineage within the tribe Gnaphalieae (Asteraceae). Species are distributed mainly in the semi-arid parts of southern Africa, but there is a disjunction to the Saharo-Sindian region where three species occur. Due partly to an unusual capitulum structure, the phylogenetic position of the group has been little understood. In addition, the monophyly of the genera has not been assessed using phylogenetic methods. A species-level phylogenetic hypothesis is presented, based on one nuclear and two chloroplast DNA regions, analysed with parsimony and Bayesian methods. Ifloga+Trichogyne constitute the "Ifloga clade" that forms one of the early-diverging lineages within Gnaphalieae. These lineages constitute a basal grade with many poorly supported nodes, precluding robust hypotheses of relationships amongst the lineages. A sister lineage to the Ifloga clade could thus not be identified, although it diverges amongst taxa formerly united in subtribe Relhaniinae. Although this subtribe is now known to be non-monophyletic, members of the Ifloga clade share with former members of Relhaniinae a previously overlooked set of leaf characters. The genus Trichogyne is monophyletic, but Ifloga is paraphyletic with respect to Trichogyne. To retain generic monophyly, all species are here transferred to the genus Ifloga. Although two of the Northern-Hemisphere species were not included in the analysis, morphological characters suggest that the three species from this region are monophyletic, in which case the Saharo-Sindian distribution is the result of a single dispersal northwards from Southern Africa. A new combination and an updated key to the species are presented. [ABSTRACT FROM AUTHOR]

This is the first comprehensive molecular investigation of the genus Lamium L. We have addressed phylogenetic relationships and presumed allopolyploid speciation by use of nuclear (NRPA2, 5S-NTS) and chloroplast (matK, psbA-trnH, rps16, trnL, trnL-F, trnS-G) DNA sequence data. Nuclear and chloroplast data were incongruent, and nuclear data showed better correlation with morphology. Bayesian and parsimony phylogenetic results show that (1) Lamium galeobdolon is sister to all remaining Lamium species; (2) Wiedemannia is nested within Lamium; (3) L. amplexicaule is polyphyletic; (4) most tetraploids are of hybrid origin; (5) L. amplexicaule var. orientale is allotetraploid; and (6) Mennema's (1989) infrageneric classification is not corroborated by molecular data. Based on the molecular results, and taking morphology into account, we suggest resurrection of two species: L. aleppicum and L. paczoskianum. [ABSTRACT FROM AUTHOR]

The phylogeny of morphologically simple algae is problematic due to insufficient morphological characters to aid in distinguishing species and relationships. The problem is further compounded because multiple evolutionary lineages of morphologically similar species occur in most well-sampled biogeographic locations; therefore, location cannot be used as a proxy for species. The phylogeny of the upright members of the Erythropeltidales is partially clarified by combining molecular data, unialgal culture observations, and worldwide sampling. Our results show that there are several well-supported lineages within the Erythropeltidales with only two morphologically recognizable taxa at present. The first is the genus Porphyrostromium, with a well-developed basal crust, which includes two Erythrotrichia species ( Porphyrostromium ligulatum comb. nov. and Porphyrostromium pulvinatum comb. nov.). The second is the branched species Erythrotrichia welwitschii (Rupr.) Batters. There are also six strongly supported Erythrotrichia carnea-like lineages. While not completely satisfactory, we propose that one lineage (lineage 2) with samples close to the type locality be designated as E. carnea with a specific isolate as an epitype. The lack of morphology to differentiate the other lineages leads to a taxonomy based solely on gene sequencing and molecular phylogeny, with rbcL sequences differentiating the lineages proposed. We hold off on proposing more species and genera until more data and samples can be gathered. [ABSTRACT FROM AUTHOR]

Phylogenetic relationships of the aquatic moss genus Platyhypnidium and terrestrial species of Rhynchostegium were explored using a phylogeny based on three DNA sequence regions, the nuclear ITS1-5.8S-ITS2, and the plastid trnL-F and trnD-T. This is the first study using trnD-T in the phyogeny of mosses. Platyhypnidium appeared polyphyletic and most of its species were found within a Rhynchostegium clade including species from four different genera: Rhynchostegium, Eriodon, Eurhynchiella and Platyhypnidium. Use of the name Rhynchostegium requires conservation against Eriodon. Within Rhynchostegium s.l., aquatic Rhynchostegium species (i.e., Platyhypnidium) were resolved in four geographically delimited groups: an Afro-European group, an American-East Asiatic group, a Malesian-Australian group and a group comprising the South American P. fuegianum together with Eriodon and Eurhynchiella. Topologies from independent analyses of plastid and nuclear data did not show conflict, and the occurrence of hybridzation events in the clade was therefore not supported. The phylogeny indicates numerous habitat shifts between terrestrial and aquatic habitats, as well as between different terrestrial (epiphytic and epigeic) habitats, which may have affected taxonomic complexity in Rhynchostegium. New morphological characters, such as a striate leaf lamina, axillary hairs composed of relatively short cells, and clearly differentiated cells of the costa, separate Platyhypnidium species within Eurhynchioideae from those in the Oxyrrhynchium-Donrichardsia clade (Helicodontioideae). Two morphologically unique specimens, Platyhypnidium muellerii from Hawaii and Platyhypnidium sp. from Northern Australia, are described as Donrichardsia bartramii and Rhynchostegium brevinerve. The new genus Hedenaesia (Helicodontioideae) is established to accommodate Platyhypnidium austrinum. [ABSTRACT FROM AUTHOR]

We present a molecular phylogeny of 26 out of the 28 currently accepted genera in the subfamily Chrysophylloideae (Sapotaceae) using parsimony, parsimony jackknifing, and Bayesian inference. A data matrix of 8984 characters was obtained from DNA sequences of seven chloroplast loci, two nuclear loci, indels coded as binary characters, and morphology. Our phylogenetic reconstruction suggests that Chrysophyllum, Pouteria, and Pradosia, as well as some sections within Chrysophyllum and Pouteria, are all polyphyletic. These taxa were previously described largely on the basis of unique combinations of states for a set of morphological characters. Mapping some of these characters onto one of the most parsimonious trees indicates that the symplesiomorphic flower in the subfamily was probably 5-merous, had stamens inserted in the tube orifice, staminodes, seeds with foliaceous cotyledons, exserted radicle, and endosperm. These characters have subsequently been lost multiple times and cannot be used as synapomorphies to support broad generic concepts. Despite the high degree of homoplasy some well-defined clades can be described on the basis of alternative character state combinations. Also, many of these well-supported clades appear to be restricted to particular geographical areas (e.g. all taxa in Australasia form a monophyletic group). Hence, we suggest that the segregate genera Aningeria, Malacantha, and Martiusella may ultimately be resurrected, and probably also Donella and Gambeya, but their circumscriptions are still unclear. One species, Chrysophyllum cuneifolium, may have originated from a hybridization event between continents where the maternal genome (cpDNA) comes from South America and the nuclear genome comes from Africa. © The Willi Hennig Society 2008. [ABSTRACT FROM AUTHOR]

We investigated the phylogenetic patterns, evolutionary processes, and their taxonomic implications, of two closely related shield-backed katydid genera endemic to the Macaronesian archipelagos: the monotypic Psalmatophanes Chopard, 1938 endemic to Madeira and Calliphona Krauss, 1892, which includes three species restricted to the Canary Islands. Two main hypotheses have been proposed to explain the origin and colonization pathways of these two genera: a single origin with subsequent sequential colonization of the islands, or three independent colonization waves from continental Africa. We used DNA sequence information from the mitochondrial genes cox1, tRNAleucine, rrnL and nad1 to infer phylogenetic relationships among Psalmatophanes and Calliphona species. Our results provide support for the independent colonization of Madeira and the Canary Islands, and suggest that Psalmatophanes is actually more closely related to the continental genus Tettigonia than to the Canarian representatives. Deep genetic divergence among Canarian species provides further support for the assignment of the Canarian species into two subgenera. Tree topology along with Bayesian-based estimates of lineage age suggest a pattern of colonization from Tenerife to La Palma, and from Tenerife to Gran Canaria with subsequent dispersal to La Gomera. We report the first collection of a Calliphona specimen in the island of El Hierro, which molecular data suggest is a recent immigrant from La Gomera. We hypothesize that the patterns of distribution and genetic divergence exhibited by Calliphona in the Canary Islands are compatible with a taxon cycle process. Our results have further implications for the higher level phylogeny of the subfamily Tettigoniinae and suggest that some of the tribes as currently delimited may not correspond to natural groups. [ABSTRACT FROM AUTHOR]

Macaranga and Mallotus (Euphorbiaceae s.s.) are two closely related, large paleo(sub)tropical genera. To investigate the phylogenetic relationships between and within them and to determine the position of related genera belonging to the subtribe Rottlerinae, we sequenced one plastid (trnL-F) and three nuclear (ITS, ncpGS, phyC) markers for species representative of these genera. The analyses demonstrated the monophyly of Macaranga and the paraphyly of Mallotus and revealed three highly supported main clades. The genera Cordemoya and Deuteromallotus and the Mallotus sections Hancea and Oliganthae form a basal Cordemoya s.l. clade. The two other clades, the Macaranga clade and the Mallotus s.s. clade (the latter with Coccoceras, Neotrewia, Octospermum, and Trewia), are sister groups. In the Macaranga clade, two basal lineages (comprising mostly sect. Pseudorottlera) and a crown group with three geographically homogenous main clades were identified. The phylogeny of the Mallotus s.s. clade is less clear because of internal conflict in all four data sets. Many of the sections and informal infrageneric groups of Macaranga and Mallotus do not appear to be monophyletic. In both the Macaranga and Mallotus s.s. clades, the African and/or Madagascan taxa are nested in Asian clades, suggesting migrations or dispersals from Asia to Africa and Madagascar. [ABSTRACT FROM AUTHOR]

Phylogenetic relationships of squamates (lizards, amphisbaenians and snakes) have received considerable attention, although no consensus has been reached concerning some basal divergences. This paper focuses on the Serpentes (snakes), whose phylogenetic position within the Squamata remains uncertain despite a number of morphological and molecular studies. Some mitogenomic studies have suggested a sister-group relationship between snakes and varanid lizards, while other studies have identified snakes and lizards as sister groups. However, recent studies using nuclear data have presented a different scenario, with snakes being more closely related to anguimorph and iguanian lizards. In this mitogenomic study we have examined the above hypotheses with the inclusion of amphisbaenians, one gekkotan and one acrodont lizard, taxa not represented in previous mitogenomic studies. To this end we have also extended the representation of snakes by sequencing five additional snake genomes: two scolecophidians ( Ramphotyphlops australis and Typhlops mirus) two henophidians ( Eunectes notaeus and Boa constrictor) and one caenophidian ( Elaphe guttata). The phylogenetic analysis recovered snakes and amphisbaenians as sister groups, thereby differing from previous hypotheses. In addition to a discussion on previous morphological and molecular studies in light of the results presented here, the current study also provides some details regarding features of the new snake mitochondrial genomes described. [ABSTRACT FROM AUTHOR]

Wall lizards of the genus Podarcis (Sauria, Lacertidae) comprise 17 currently recognized species in southern Europe, where they are the predominant reptile group. The taxonomy of Podarcis is complex and unstable. Based on DNA sequence data the species of Podarcis falls into four main groups that have substantial geographical conherence (western island group, southwestern group, Italian group and Balkan group). The Balkan species are divided in two subgroups: the subgroup of Podarcis taurica ( P. taurica, P. milensis, P. gaigeae and perhaps P. melisellensis), and the subgroup of Podarcis erhardii ( P. erhardii and P. peloponnesiaca). We addressed the question of phylogenetic relations among the species of the P. taurica subgroup encountered in Greece, as they can be inferred from partial mtDNA (cyt b and 16S) sequences. Our data support the monophyly of P. taurica subgroup and suggest that P. gaigeae, P. milensis and P. melisellensis form a clade, which thereinafter connects to P. taurica. Within the previous clade, P. gaigeae is more closely related to P. milensis than to P. melisellensis. However, the specimens of P. taurica were subdivided in two different groups. The first one includes the specimens from northeastern Greece, and the other group includes the specimens from the rest of continental Greece and Ionian islands. Because the molecular clock of the cyt b and 16 rRNA genes was not rejected in our model test, it is possible to estimate times of speciation events. Based on the splitting of the island of Crete from Peloponnisos [ c. 5 million years ago (Ma)], the evolutionary rate for the cyt b is 1.55% per million years (Myr) and for the 16S rRNA is 0.46% per Myr. These results suggest that the evolutionary history of P. taurica in Greece is more complex than a single evolutionary invasion. The data analysed, stress the need for a reconsideration of the evolutionary history of Greek Podarcis species and help overcome difficulties that classical taxonomy has encountered at both the species level. [ABSTRACT FROM AUTHOR]

A preliminary phylogenetic analysis of the subfamily Aleocharinae Fleming is presented based on molecular characters. The data set comprised partial mitochondrial COI (925 bp), COII(372 bp), 12S rDNA (325-330 bp), and nearly complete sequences of 18S rDNA (1705-1771 bp) for 66 group taxa in fifteen tribes and four outgroup taxa. The sequences were analysed using parsimony and Bayesian methods. The results show that tribes Aleocharini, Lomechusini, Myllaenini, and the subtribe Gyrophaenina are supported as monophyletic groups. Phylogentic relationships between tribes were not clearly resolved in this study. Deinopsini and Trichopseniini are recovered as basal groups. [ABSTRACT FROM AUTHOR]