Parsimonious Cladograms Research Articles

Sequence typing reveals extensive strain diversity of the Lyme borreliosis agents Borrelia burgdorferi in North America and Borrelia afzelii in Europe.

The genetic polymorphism of Borrelia burgdorferi and Borrelia afzelii, two species that cause Lyme borreliosis, was estimated by sequence typing of four loci: the rrs-rrlA intergenic spacer (IGS) and the outer-membrane-protein gene p66 on the chromosome, and the outer-membrane-protein genes ospA and ospC on plasmids. The major sources of DNA for PCR amplification and sequencing were samples of the B. burgdorferi tick vector Ixodes scapularis, collected at a field site in an endemic region of the north-eastern United States, and the B. afzelii vector Ixodes ricinus, collected at a similar site in southern Sweden. The sequences were compared with those of reference strains and skin biopsy isolates, as well as database sequences. For B. burgdorferi, 10-13 alleles for each of the 4 loci, and a total of 9 distinct clonal lineages with linkage of all 4 loci, were found. For B. afzelii, 2 loci, ospC and IGS, were examined, and 11 IGS genotypes, 12 ospC alleles, and a total of 9 linkage groups were identified. The genetic variants of B. burgdorferi and B. afzelii among samples from the field sites accounted for the greater part of the genetic diversity previously reported from larger areas of the north-eastern United States and central and northern Europe. Although ospC alleles of both species had higher nucleotide diversity than other loci, the ospC locus showed evidence of intragenic recombination and was unsuitable for phylogenetic inference. In contrast, there was no detectable recombination at the IGS locus of B. burgdorferi. Moreover, beyond the signature nucleotides that specified 10 IGS genotypes, there were additional nucleotide polymorphisms that defined a total of 24 subtypes. Maximum-likelihood and parsimony cladograms of B. burgdorferi aligned IGS sequences revealed the subtype sequences to be terminal branches of clades, and the existence of at least three monophyletic lineages within B. burgdorferi. It is concluded that B. burgdorferi and B. afzelii have greater genetic diversity than had previously been estimated, and that the IGS locus alone is sufficient for strain typing and phylogenetic studies.

Phylogenetic Relationships in the Genus Onoseris (Asteraceae, Mutisieae) Inferred from Morphology

Abstract Onoseris (Asteraceae, Mutisieae) is a genus of 31 species distributed from Mexico to Argentina through the Andes with its center of diversity in Peru. A phylogenetic analysis based on a detailed morphological study is provided. Urmenetea is used as the outgroup. Three most parsimonious cladograms are obtained based on the complete data set using Paup* 4.0b8. Two monophyletic groups are recognized: 1. Species with petiolate leaves, palmately veined blades with hastate base, and few-headed capitulescences, rarely thyrsoid capitulescences (O. acerifolia, O. alata, O. brasiliensis, O. cabrerae, O. castelnaeana, O. costaricensis, O. donnell-smithii, O. drakeana, O. fraterna, O. hastata, O. macbridei, O. onoseroides, O. peruviana, O. purpurea, O. sagittata, O. silvatica, and O. speciosa). 2. Species with sessile or subsessile leaves, elliptic and pinnately veined blades with attenuate base, and solitary capitula (O. albicans, O. amplexicaulis, O annua, O. chrysactinioides, O cumingii, O. gnaphalioides,...

The evolution of host plant manipulation by insects: molecular and ecological evidence from gall-forming aphids on Pistacia

One of the most striking characteristics of gall-forming insects is the variability in gall position, morphology, and complexity. Our knowledge of the driving forces behind the evolutionary divergence of gall types is limited. Natural enemies, competition, and behavioral constraints might be involved. We present a cladogram, based on sequences of COI and COII (1952 bp), of mitochondrial DNA for the evolution of 14 species of gall-forming aphids (Fordinae). These insects induce five gall types with remarkable morphological variation on Pistacia spp. hosts. The parsimony cladogram divides the Fordinae into three lineages, Fordini and Baizongiini, and a third (new) sister group including the previously Fordini member, Smynthurodes betae (West). We then use ecological data to trace and explain the evolution of gall morphology. The aphids seem to have evolved gradually towards better ability to manipulate their host plant, induce stronger sinks, and gain higher reproductive success. We suggest that the ancestral gall type was a simple, open, “pea”-sized gall located on the leaflet midvein. Some Fordini and S. betae evolved a two-gall life cycle, inducing a new gall type on the leaflet margin. The Baizongiini improved the manipulation of their host by inducing larger galls near the midvein, with stronger sinks supporting thousands of aphids. Similar gall types are induced at similar sites on different Pistacia hosts suggesting control of the aphids on gall morphology and frequent host shifts. Thus, even extreme specialization (specific gall and host) is flexible.

Skelton P, Smith A. 2002. Accompanying booklet written by Monks N. Cladistics: a practical primer on CD-ROM

Skelton P, Smith A. 2002. Accompanying booklet written by Monks N. Cladistics: a practical primer on CD-ROM

Areas of endemism for passerine birds in the Atlantic forest, South America

ABSTRACTAim To use the method of parsimony analysis of endemism to identify areas of endemism for passerine birds in the Atlantic Forest, South America, and to compare the locations of these areas with areas previously identified for birds as well as other taxa.Location The Atlantic Forest, eastern South America.Methods We analysed a matrix composed of the presence (1) or absence (0) of 140 endemic species in 24 quadrats of 1 × 1 degree distributed along the Atlantic Forest to find the most parsimonious area cladogram.Results Fourteen most parsimonious cladograms were found and then summarized in a single consensus tree. Four areas of endemism were identified: Pernambuco, Central Bahia, Coastal Bahia, and Serra do Mar.Main conclusions Avian areas of endemism in the Atlantic Forest have significant generality, as they are highly nonrandom and congruent with those of other groups of organisms. A first hypothesis about the historical relationships among the four areas of avian endemism in the Atlantic Forest is delineated. There is a basal dichotomy among areas of endemism in the Atlantic Forest, with Pernambuco forming a northern cluster and Coastal Bahia, Central Bahia and Serra do Mar comprising a southern cluster. Within the southern cluster, Central Bahia and Serra do Mar are more closely related to each other than to Coastal Bahia.

Phylogeny of Peyerimhoffia Kieffer, with the revision of the species (Diptera: Sciaridae)

AbstractThe genus Peyerimhoffia Kieffer (type-species Sciara vagabunda Winnertz), currently classified as a subgenus of Cratyna Winnertz (type-species Cratyna atra Winnertz) is redefined and its phylogeny studied by parsimony analysis. Cladistic analysis using sixty-four morphological characters from adult males of sixty-six ingroup and one outgroup species produced thirty most parsimonious cladograms. The strict consensus cladogram of these showed unambiguously that the type-species of Peyerimhoffia and the species currently referred to the Corynoptera crassistylata group form a monophyletic unit. The phylogenetic hypothesis obtained also suggested that Cratyna s.l. in its current concept is non-monophyletic and that Peyerimhoffia deserves generic status. The genus is Holarctic-Oriental in distribution and includes the following species, which are keyed and described or diagnosed: Peyerimhoffia alpina (Mohrig) (Austrian Alps, Italy, Spain, Canada: Quebec), P. calva sp.n. (Nepal), P. collina sp.n. (Russia: Altay region), P. crassistylata (Frey) (central and northern Europe, Altay region, Kurile Islands), P. curvata (Mohrig & Mamaev) (Russia: Tuva region), P. infera sp.n. (northern Europe), P. ioculatoria (Mohrig) (Nepal), P. menzeli sp.n. (northern Europe), P. obtusicauda (Strobl) (southern Europe), P. semicurvata (Mohrig) (Nepal, Burma), P. subcurvata (Mohrig) (Nepal), P. thula sp.n. (northern Europe), P. ultima sp.n. (Nepal), and P. vagabunda (Winnertz) (Europe, eastern Palaearctic). Plastosciara perniciosa Edwards, Hyperlasion curtipennis Edwards, and Plastosciara hybrida Mohrig & Mamaev are excluded, the former appearing more closely related to Epidapus Haliday, the latter two to Spathobdella Frey.

The spiny devil katydids, Panacanthus Walker (Orthoptera: Tettigoniidae): an evolutionary study of acoustic behaviour and morphological traits

Abstract. A cladistic analysis and systematic revision of the genus Panacanthus accompanies the description of three new species, with calling songs reported for four species. The evolutionary origin of spines is considered as a defensive mechanism in Panacanthus; both morphological and behavioural (i.e. acoustic) traits allow inferences about relationships. Phylogenetic analysis produced one most parsimonious cladogram eighty‐two steps long, with the ensemble consistency index = 0.84. Panacanthus cuspidatus and P. pallicornis (formerly Storniza Walker 1869, Martinezia Bolivar 1881) are properly incorporated in Panacanthus. On morphology, Panacanthus is more related to the Neotropical Copiphora and Lirometopum than to the Old World Lesina. Character analysis reveals that in Panacanthus the ancestral condition of calling song resonance (the production of musical sounds) has given rise to a more nonresonant (transient) stridulation. A correlation between the production of more complex sound waves and spinous protection of the body (especially the pronotum) is noted. Because early workers grouped Panacanthus with other spiny genera, based on pronotal morphology, we present a critique of the evolutionary and ecological implications of the development of defensive spines in this genus. This approach may be applied to other taxa using a similar protective mechanism. We advise against arrangement of the pronotal, cephalic and femoral armature as a homologous characteristic across subfamilies. Several pronotal processes and modifications evolved independently in other genera of Conocephalinae, Hetrodinae, Pseudophyllinae and Phaneropterinae. The pronotal structure of Panacanthus is unique and may be taken as a synapomorphic characteristic of all its species and as an autapomorphic feature of the genus.

Parsimony Analysis of Endemicity (PAE) of Mexican hydrological basins based on helminth parasites of freshwater fishes

AbstractAim The distributional patterns of helminthological fauna of freshwater fishes were analysed to postulate a general hypothesis on the relationships of some Mexican hydrological systems.Location Eight hydrological systems of central and eastern Mexico were studied and compared with records from Nicaragua.Methods A Parsimony Analysis of Endemicity (PAE) was applied to the presence/absence of ninety‐two helminth parasite taxa (Monogeneans, Digeneans, Cestodes, Acanthocephalans and Nematodes) of freshwater fishes, from eight Mexican hydrological systems, using the Hennig86 program.Results The results represent the first attempt for a biogeographical analysis through application of the PAE method to the distributional patterns of helminth parasites of freshwater fishes in Mexico. A single most parsimonious cladogram was obtained, which grouped all the Neotropical systems in accordance with previous proposals based on other plant and animal taxa.Main conclusions The most basal systems were Santiago and Lerma basins, which exhibited Nearctic affinities. The remaining areas of the cladogram showed Neotropical affinities. All the southeastern systems were grouped in a clade with the Nicaragua system, providing support for a ‘Mesoamerican province’ based on helminth parasites of cichlids. The cladogram also suggests that the treatment of the Lerma‐Santiago basin as a single biogeographical unit is inaccurate and that they should be treated as separate systems.

A new species of Syncuaria Gilbert, 1927 (Nematoda: Acuarioidea: Acuariidae) in the wood stork, Mycteria americana L. (Aves: Ciconiiformes: Ciconiidae) from the Area de Conservacion Guanacaste, Costa Rica.

Syncuaria mycteriae n. sp. (Nematoda: Acuarioidea) was collected under the lining of the gizzard of a wood stork, Mycteria americana L., from the Area de Conservacion Guanacaste, Costa Rica. The new species can be distinguished from all known species of Syncuaria by having irregular dotted ornamentations on the caudal alae of males, a complex distal end of the left spicule comprising 3 protuberances, and a spicule ratio of 1:9.3. Preliminary phylogenetic analysis of 11 Syncuaria spp. based on 9 morphological characters produced 2 equally parsimonious cladograms with a consistency index of 85%, differing only in the placement of S. hargilae. The phylogenetic analysis suggests that the new species is the sister species of S. leptoptili, whose male members have a single protuberance on the left spicule. Furthermore, the analysis suggests that the plesiomorphic host group for the genus is Ciconiiformes, specifically Ciconiidae (host for 5 species), with 2 species occurring in Threskiornithidae (also Ciconiiformes), possibly as a result of cospeciation, and 2 species each occurring in Pelecaniformes and Podicipediformes, resulting from 4 episodes of speciation by host switching.

Search‐based optimization

AbstractThe problem of determining the minimum cost hypothetical ancestral sequences for a given cladogram is known to be NP‐complete (Wang and Jiang, 1994). Traditionally, point estimations of hypothetical ancestral sequences have been used to gain heuristic, upper bounds on cladogram cost. These include procedures with such diverse approaches as non‐additive optimization of multiple sequence alignment, direct optimization (Wheeler, 1996), and fixed‐state character optimization (Wheeler, 1999). A method is proposed here which, by extending fixed‐state character optimization, replaces the estimation process with a search. This form of optimization examines a diversity of potential state solutions for cost‐efficient hypothetical ancestral sequences and can result in greatly more parsimonious cladograms. Additionally, such an approach can be applied to other NP‐complete phylogenetic optimization problems such as genomic break‐point analysis.

Phylogenetics of Sigmodontinae (Rodentia, Muroidea, Cricetidae), with special reference to the akodont group, and with additional comments on historical biogeography

AbstractThis is the first cladistic analysis of sigmodontine rodents (Cricetidae, Sigmodontinae) based on nuclear and mitochondrial DNA sequences. Two most parsimonious cladograms (7410 steps in length; CI=0.199; RI=0.523) were discovered. Sigmodontinae appears well supported. Sigmodon is sister to the remaining living sigmodontines. It is shown that Euneomys is not a phyllotine and that the Reithrodon group is not monophyletic. Results corroborate that the abrothricines form a natural group that is not part of the akodont radiation. The akodontine tribe is well supported, and is composed of five main clades, whose limits and relationships are thoroughly discussed. For instance, the scapteromyines do not form a natural group and they fall within the akodontine clade. Additionally, I present some taxonomic judgments and comments on the historical biogeography of sigmodontines in the light of the newly discovered relationships. For example, five akodontine divisions are suggested: the Akodon, the Bibimys, the Blarinomys, the Oxymycterus, and the Scapteromys Divisions. It is shown that traditional hypotheses of sigmodontine historical biogeography are falsified by the recovered topology.

Phylogenetics of Sigmodontinae (Rodentia, Muroidea, Cricetidae), with special reference to the akodont group, and with additional comments on historical biogeography

This is the first cladistic analysis of sigmodontine rodents (Cricetidae, Sigmodontinae) based on nuclear and mitochondrial DNA sequences. Two most parsimonious cladograms (7410 steps in length; CI=0.199; RI=0.523) were discovered. Sigmodontinae appears well supported. Sigmodon is sister to the remaining living sigmodontines. It is shown that Euneomys is not a phyllotine and that the Reithrodon group is not monophyletic. Results corroborate that the abrothricines form a natural group that is not part of the akodont radiation. The akodontine tribe is well supported, and is composed of five main clades, whose limits and relationships are thoroughly discussed. For instance, the scapteromyines do not form a natural group and they fall within the akodontine clade. Additionally, I present some taxonomic judgments and comments on the historical biogeography of sigmodontines in the light of the newly discovered relationships. For example, five akodontine divisions are suggested: the Akodon, the Bibimys, the Blarinomys, the Oxymycterus, and the Scapteromys Divisions. It is shown that traditional hypotheses of sigmodontine historical biogeography are falsified by the recovered topology.

Search-based optimization

The problem of determining the minimum cost hypothetical ancestral sequences for a given cladogram is known to be NP-complete ( Wang and Jiang, 1994). Traditionally, point estimations of hypothetical ancestral sequences have been used to gain heuristic, upper bounds on cladogram cost. These include procedures with such diverse approaches as non-additive optimization of multiple sequence alignment, direct optimization ( Wheeler, 1996), and fixed-state character optimization ( Wheeler, 1999). A method is proposed here which, by extending fixed-state character optimization, replaces the estimation process with a search. This form of optimization examines a diversity of potential state solutions for cost-efficient hypothetical ancestral sequences and can result in greatly more parsimonious cladograms. Additionally, such an approach can be applied to other NP-complete phylogenetic optimization problems such as genomic break-point analysis.

A Phylogenetic Study of the Order Asterales Using One Morphological and Three Molecular Data Sets

We obtained two most parsimonious cladograms using a data set of 100 characters derived from morphology, anatomy, embryology, chemistry, and karyology, combined with three nucleotide sequence data sets (the chloroplast genes atpB, ndhF, and rbcL) in a phylogenetic analysis of all 12 currently recognized families in the angiosperm order Asterales, represented by 40 genera. Most clades were supported by a jackknife value of at least 50% and a Bremer support of 5 or more. Rousseaceae sensu lato (including Carpodetaceae), together with Pentaphragmataceae and Campanulaceae s.l., is the sister group to the rest of the Asterales. A sister group relationship between Donatia and Stylidiaceae is well supported both morphologically and by molecular data, and we suggest that Donatia should again be treated as a subfamily in Stylidiaceae. The sister group relationship between Calyceraceae and Asteraceae is well supported.

The phylogeny of diving beetles (Coleoptera: Dytiscidae) and the evolution of sexual conflict

A model of evolution based on conflicts of interest between the sexes over mating decisions is examined in relation to diving beetles (Dytiscidae). The model predicts the following evolutionary sequence: (1) cost to females of mating increases, (2) females evolve behavioural resistance to male mating attempts, (3) males evolve devices to overcome female resistance, and (4) females evolve morphological counter-adaptations to the male devices. This model is tested using species of Dytiscidae, in which (1) some species have a very long mating duration while others mate quickly, (2) females of some species resist male mating attempts by swift and erratic swimming when seized by a male, (3) males of some species possess a grasping device in the form of sucker-shaped setae on the legs used to adhere to the pronota or elytra of females prior to mating, and (4) females of some species have a modified dorsal cuticle with irregular sculpturing which appears to interfere with the male adhesive setae. The predicted order of evolution of some of these features was tested in a cladistic analysis of 52 taxa in Dytiscidae and Hygrobiidae using characters from adult and larval morphology and a portion of the gene wingless. The combined analysis resulted in nine most parsimonious cladograms. The consensus cladogram of these indicates that male sucker setae arose a single time in a clade of Dytiscinae. Nested within this clade are five groups with an independently derived, modified dorsal cuticle in females. This pattern of characters in Dytiscinae is consistent with the prediction implied by the model of sexual selection. The utility of wingless as a marker for phylogenetic analysis of diving beetles is discussed, and the resulting phylogeny is compared with previous analyses and current classification. © 2003 The Linnean Society of London, Biological Journal of the Linnean Society, 2003, 79, 359–388.

Phylogeny of Neotropical oryzomyine rodents (Muridae: Sigmodontinae) based on the nuclear IRBP exon

Sigmodontine rodents are the most diverse family-level mammalian clade in the Neotropical region, with about 70 genera and 320 recognized species. Partial sequences (1266 bp) from the first exon of the nuclear gene encoding the Interphotoreceptor Retinoid Binding Protein (IRBP) were used to infer the phylogenetic relationships among 44 species representing all 16 currently recognized genera of the largest sigmodontine tribe, the Oryzomyini. Monophyly of the tribe was assessed relative to 15 non-oryzomyine sigmodontine taxa representing all major sigmodontine lineages. Twelve taxa from seven muroid subfamilies were used as outgroups. The resulting matrix included 71 taxa and 386 parsimony-informative characters. Phylogenetic analysis of this matrix resulted in 16 equally parsimonious cladograms, which contained the following well-supported groups: (i) a monophyletic Oryzomyini, (ii) a clade containing all oryzomyines except Scolomys and Zygodontomys, (iii) a clade containing Oecomys, Handleyomys, and several species of forest-dwelling Oryzomys, and (iv) a clade containing the remaining oryzomyine taxa. The last clade is composed of two large subclades, each with lower nodal support, containing the following taxa: (i) Microryzomys, Oligoryzomys, Neacomys, and Oryzomys balneator; (ii) Holochilus, Lundomys, Pseudoryzomys, Nectomys, Amphinectomys, Sigmodontomys, and several species of open-vegetation or semiaquatic Oryzomys. Regarding relationships among non-oryzomyine taxa, sigmodontines, neotomines, and tylomyines do not form a monophyletic group; a clade containing Rheomys and Sigmodon is basal relative to all other sigmodontines; and the remaining sigmodontines are grouped in three clades: the first containing Thomasomyini, Akodontini, and Reithrodon; the second containing Abrothrichini, and Phyllotini, plus Wiedomys, Juliomys, Irenomys, and Delomys; and the third containing the oryzomyines. No conflict is observed between IRBP results and previous robust hypotheses from mitochondrial data, while a single case of incongruence is present between the IRBP topology and robust hypothesis from morphological studies.

Phylogenetic analysis of higher‐level relationships of Odonata

Abstract.This is the most comprehensive analysis of higher‐level relationships in Odonata conducted thus far. The analysis was based on a detailed study of the skeletal morphology and wing venation of adults, complemented with a few larval characters, resulting in 122 phylogenetically informative characters. Eighty‐five genera from forty‐five currently recognized families and subfamilies were examined. In most cases, several species were chosen to serve as exemplars for a given genus. The seven fossil outgroup taxa included were exemplar genera from five successively more distant odonatoid orders and suborders: Tarsophlebiidae (the closest sister group of Odonata, previously placed as a family within ‘Anisozygoptera’), Archizygoptera, Protanisoptera, Protodonata and Geroptera. Parsimony analysis of the data, in which characters were treated both under equal weights and implied weighting, produced cladograms that were highly congruent, and in spite of considerable homoplasy in the odonate data, many groupings in the most parsimonious cladograms were well supported in all analyses, as indicated by Bremer support. The analyses supported the monophyly of both Anisoptera and Zygoptera, contrary to the well known hypothesis of zygopteran paraphyly. Within Zygoptera, two large sister clades were indicated, one comprised of the classical (Selysian) Calopterygoidea, except that Amphipterygidae, which have traditionally been placed as a calopterygoid family, nested within the other large zygopteran clade comprised of Fraser's ‘Lestinoidea’ plus ‘Coenagrionoidea’ (both of which were shown to be paraphyletic as currently defined).Philogangaalone appeared as the sister group to the rest of the Zygoptera in unweighted cladograms, whereasPhiloganga + Diphlebiacomprised the sister group to the remaining Zygoptera in all weighted cladograms. ‘Anisozygoptera’ was confirmed as a paraphyletic assemblage that forms a ‘grade’ towards the true Anisoptera, withEpiophlebiaas the most basal taxon. Within Anisoptera, Petaluridae appeared as the sister group to other dragonflies.

Phylogenetic reassessment of the five forewing radial‐veined tribes of Riodininae (Lepidoptera: Riodinidae)

Abstract.The relationships among the genera and tribal groupings of Riodininae with five forewing radial veins, and between these and tribes with four forewing radial veins, were examined using a phylogenetic analysis. Using the type species from all sixteen genera in the tribal groupings Eurybiini, Mesosemiini and incertae sedis (a presumed paraphyletic group of loosely related genera), and representatives from the four forewing radial‐veined riodinine tribes, thirty‐five new and traditional characters were coded from adult ecology, wing venation and pattern, the adult head and body, male and female genitalia, and early stage ecology and morphology. The majority of characters are illustrated. Phylogenetic analysis of these data produced five equally most parsimonious cladograms using equal weights and after successive weighting. The strict consensus of these confirms the monophyly of Eurybiini and Mesosemiini as currently conceived, but also indicates several higher‐level relationships not previously hypothesized. Mesosemiini is here more broadly defined to also include the entire incertae sedis section, and the tribe is divided into Mesosemiina, for the previously delimited Mesosemiini plus Eunogyra and Teratophthalma, and Napaeina, subtr.n. for the incertae sedis section minus these two genera. The following hypothesis of relationships is tentatively proposed for the basal clades of Riodininae: Mesosemiini + (Eurybiini + remainder of Riodininae). These new hypotheses, and the characters supporting them, are discussed and compared with those previously proposed.

Comparative osteology and phylogenetic systematics of fossil and living bony-tongue fishes (Actinopterygii, Teleostei, Osteoglossomorpha)

Several recent studies using analyses of morphological characters have addressed the interrelationships of Osteoglossomorpha, a group that sometimes is considered the living sister group of all other living teleosts. Many characters used in these studies were found to be poorly defined, to be coded incorrectly or illogically, or to display more variation than was described. The goal of this study is to address these concerns and contribute generally to knowledge of the morphology and systematic relationships of osteoglossomorphs. Analysis of 72 characters (65 informative) scored for 20 genera resulted in two most parsimonious cladograms (171 steps, CI = 0.6433, CI = 0.6139 excluding uninformative characters, HI = 0.3977, HI = 0.3861 excluding uninformative characters; RI = 0.7782; RC = 0.5006). Osteoglossomorpha is supported by both synapomorphies and homoplasies, although its monophyly was not truly tested in this analysis (only a single outgroup, Elops , was included in the analysis). The only difference in the topologies of these cladograms is in the position of †Lycoptera (recovered as either the sister group of all other osteoglossomorphs sampled or of †Eohiodon +Hiodon ). †Ostariostoma is recovered as the sister group of all non-hiodontiform osteoglossomorphs. Mormyrids are the sister group of notopterids + osteoglossids. This clade has not been found in other recent analyses. Mormyrids and notopterids usually are considered more closely related to each other than to any other group; characters not included here support this relationship and future consideration of these characters must be made. Although almost completely dichotomous, many nodes of the resulting trees lack rigorous support. For example, †Palaeonotopterus is interpreted as the sister group of all mormyrids sampled, although for this taxon only 22% of characters could be scored. © 2003 The Linnean Society of London. Zoological Journal of the Linnean Society , 2003, 137, 1−100.

The Neotropical Weevil Genus Entimus (Coleoptera: Curculionidae: Entiminae): Cladistics, Biogeography, and Modes of Speciation

Abstract The weevil genus Entimus Germar is a monophyletic taxon, recognized by a combination of the following characters: large size (12–45 mm); presence of green, blue, and gold iridescent scales; antennae reaching base of prothorax, with second funicular article scarcely longer than first; widened frontal groove; pronotum as wide as long, granulate; elytra triangularly shaped; tibiae not crenulated or dentate within; scutellum protruding; and aedeagal apex slightly acute. It includes seven species, which are endemic to the Neotropics, ranging from Mesoamerica to northeastern Argentina. A cladistic analysis was carried out using 16 characters from external morphology, body vestiture, and male genitalia. The analysis yielded four equally parsimonious cladograms, each with 33 steps, a consistency index of 0.60, and a retention index of 0.53. After successive weighting, a single cladogram resulted, with 105 steps, a consistency index of 0.89, and a retention index of 0.90. According to this cladogram, the ...