Comparative biochemical study of brain phospholipids in insects

Studies have been made on the content of total phospholipids (PL) and their separate families in the brain of larvae and imago of the insect species Blaberus giganteus, Periplaneta americana, Tenebrio molitor and Barathra brassicae. It was shown that during larval-pupal-imaginal transformation in T. molitor and B. brassicae the content of total PL increases by 17 and 14% respectively, whereas in B. giganteus and P. americana PL concentration undergoes only insignificant changes. With respect to total PL content the species investigated form the following sequence: B. brassicae greater than T. molitor greater than P. americana greater than B. giganteus. In larval and imago forms of these insects phosphatidylethanolamine, phosphatidylcholine, phosphatidylserine, phosphatidylinositol, sphingomyelin and polyglycerophosphatide were found in the brain. Besides, in the brain of B. giganteus and P. americana lysophosphatidylethanolamine and in the brain of T. molitor -- phosphatidic acid are present. Qualitative PL composition in larval and imago forms is identical, while quantitative ratio of separate fractions differs insignificantly. In all the species investigated, phosphatidylethanolamine and phosphatidylcholine are the most abundant phospholipids.     

Taxonomic revision of hispaniola tiger beetles in the genus brasiella rivalier 1954 (coleoptera, carabidae, cicindelinae)

The Brasiella tiger beetle fauna on Hispaniola, the second largest island of the Greater Antilles, has more species diversity than currently recognized as all populations previously have been assigned to the insular endemic Brasiella dominicana (Mandl). A comparative study of adult morphology, particularly male genitalic and female abdominal characters, for available Brasiella specimens from populations on Hispaniola, proposes eight additional new species also endemic to this island. Except for three sympatric species in the Sierra de Baoruco in southern Dominican Republic occurring in different habitats, all the Brasiella on Hispaniola appear to be allopatric. Most species occur in the major mountainous regions of Hispaniola. Two species, however, are known only from river floodplains in the southern coastal plain of the Dominican Republic. Brasiella dominicana (Mandl) and Brasiella ocoa, new species, occur along river floodplains emanating from the eastern end of the Cordillera Central in the Dominican Republic. Two new Brasiella species, Brasiella bellorum, and Brasiella philipi, occur in the Cordillera Central, Dominican Republic, the former species from central portions, and the latter species from north slopes of this mountain range, respectively. Three new Brasiella species, Brasiella rawlinsi, Brasiella iviei, and Brasiella youngi, are isolated in the Sierra de Baoruco, Dominican Republic, where each occupies a different habitat along an altitudinal gradient. The two new Brasiella species in Haiti are Brasiella darlingtoniana, in the Massif de la Selle, and Brasiella davidsoni, in the Massif de la Hotte. All nine Brasiella species on Hispaniola, along with Brasiella viridicollis (Dejean) and its two subspecies on Cuba, belong to the viridicollis species group of the genus Brasiella based on criteria presented in earlier published phylogenetic studies of Brazilian and West Indian tiger beetles. The subspecies Brasiella viridicollis fernandozayasi (Kippenhan, Ivie and Hopp) may represent a distinct species within this species group, whereas removal of Brasiella wickhami (W. Horn) from this species group seems warranted based on evidence presented. A general overview of species relationships for the Brasiella on Hispaniola are discussed, along with the current and ancestral geographic distributions of the Brasiella viridicollis species group in the West Indies.     

Molecular systematics of Hispaniolan pupfishes (Cyprinodontidae: Cyprinodon): implications for the biogeography of insular Caribbean fishes

We used sequence variation in the mtDNA control-region and ND2 and cyt b genes to assess the systematics and biogeography of the five species of pupfish (Cyprinodon) on Hispaniola. These include four endemics, the relatively large-bodied Cyprinodon bondi, Cyprinodon nichollsi, and Cyprinodon sp., each from a separate lake in southwestern Hispaniola, and Cyprinodon higuey from a coastal lake in eastern Hispaniola. The fifth species consists of coastal populations referable to Cyprinodon variegatus riverendi. The results indicate that Hispaniola has been invaded by at least two forms, first by a late Pliocene progenitor of Cyprinodon variegatus ovinus and the large-bodied Hispaniolan species, and, more recently, by one or more ancestral forms allied with Cyprinodon variegatus variegatus and C. v. riverendi. Levels of divergence indicate that large expanses of open sea have not acted as long-term barriers to inter-island dispersal of cyprinodontiform fishes. This study, together with the molecular systematics of other insular Caribbean fishes, indicates that most insular groups originated from late Neogene dispersal from the mainland. The patterns of mtDNA variation in Cyprinodon showed little congruence with the species/subspecies taxonomy.     

Helminth parasitism in martens (Martes americana) and ermines (Mustela erminea) from Washington, with comments on the distribution of Trichinella spiralis

Helminths are reported for the first time from ermines (Mustela erminea) and martens (Martes americana) in Washington (USA). Among 22 adult ermines, 41% were infected by one or more of five species (Taenia mustelae, Alaria mustelae, Molineus patens, M. mustelae and Trichinella spiralis). Among 78 adult martens from three geographic localities, the prevalence was 83%. Nine species were identified (Mesocestoides sp., T. mustelae and T. martis americana, Euryhelmis squamula, M. patens, Baylisascaris devosi, Physaloptera sp., Soboliphyme baturini and T. spiralis). Trichinella spiralis occurred with a maximum prevalence of 50% in martens, but only occurred in 9% of ermines. Compression and digestion techniques provided a similar estimate of prevalence of T. spiralis, yet neither was entirely accurate in identifying all infected hosts. The species richness of the helminth community of martens in Washington was greater than that reported from other regions of North America.     

Screening of Costa Rican Trichilia species for biological activity against the larvae of Spodoptera litura (Lepidoptera: Noctuidae)

Crude methanolic extracts made from the twigs of 39 plant samples from six species of Trichilia collected in Costa Rica, were incorporated into artificial diet and fed to neonate Spodoptera litura larvae. All six plant species tested significantly reduced larval growth after 7 and 10 days. The most active species was T. americana, reducing growth, on average, to 3.9% of control at 1000ppm fresh weight. The least active, on average, was T. glabra. A twig extract of T. americana proved to be more active than wood, bark or leaf extracts, with the twig extract reducing growth of S. litura larvae by 50% (EC(50)) at a dietary concentration of 17.2ppm. When T. americana wood extract was incorporated into artificial diet (10, 25, 50 and 75ppm) and fed to S. litura larvae throughout larval development, growth was slowed and the final weight of pupae and adults was reduced. At higher extract concentrations (50 and 75ppm) larvae entered one or two supernumerary instars before pupation occurred. This was shown to be due to both starvation and to post-ingestive activity of the extract.     

Cuticular hydrocarbon profiles and aggregation in four Periplaneta species (Insecta: Dictyoptera)

Cuticular hydrocarbon (CH) profiles of four Periplaneta species were compared and their role in aggregation and interspecific recognition was evaluated. CH profiles are species specific and include from 19 to 25 hydrocarbons. P. brunnea, P. fuliginosa and P. australasiae have more CH components in common with one another than with P. americana. P. americana hydrocarbons include components from 24 to 43 carbon atoms but hydrocarbons for the three other species range from 21 to 41 atoms. The major compound in CH profiles in P. americana is 6,9-heptacosadiene that is absent from the three other species. The major compound in CH profiles of P. Brunnea and P. fuliginosa is 13-methyl pentacosane that is not found in the CH profile of P. americana. Major compounds in P. australasiae species are tricosene and 13-methyl pentacosane, respectively, in males and females. Binary choice tests demonstrated that specific CH extracts induced aggregation in the four species. High CH amounts were required to induce aggregation of P. americana and P. brunnea on conditioned sites, whereas low amounts were sufficient to induce aggregation of P. fuliginosa and P. australasiae. These results suggest that CHs are involved in aggregation and interspecific recognition.     

Patterns of molecular variation and evolution in Drosophila americana and its relatives

We present the results of a survey of DNA sequence variability at X-linked and autosomal loci in Drosophila americana and of patterns of DNA sequence evolution among D. americana and four other related species in the virilis group of Drosophila. D. americana shows a typical level of silent polymorphism for a Drosophila species, but has an unusually low ratio of nonsynonymous to silent variation. Both D. virilis and D. americana also show a low ratio of nonsynonymous to synonymous substitutions along their respective lineages since the split from their common ancestor. The proportion of amino acid substitutions between D. americana and its relatives that are caused by positive selection, as estimated by extensions of the McDonald-Kreitman test, appears to be unusually high. We cannot, however, exclude the possibility that this reflects a recent increase in the intensity of selection on nonsynonymous mutations in D. americana and D. virilis. We also find that base composition at neutral sites appears to be in overall equilibrium among these species, but there is evidence for departure from equilibrium for codon usage in some lineages.     

<Emphasis Type="Italic">Badiera subrhombifolia</Emphasis> (Polygalaceae), a new species from Hispaniola

Badiera subrhombifolia is newly described from Hispaniola, where it co-occurs with B. fuertesii and B. penaea. Badiera subrhombifolia lacks the long peduncle of the former species and the scabrous leaves of the latter; it is also often distinguishable by subrhomboid, triplinerved leaves. This new species is a near endemic to high montane forests of the “south island” of Hispaniola, i.e., the Massif de la Hotte, Massif de la Selle, and Sierra de Bahoruco.     

Zoosporic Phycomycetes from Hispaniola

Summary Forty-five taxa of zoosporic Phycomycetes are recorded from Hispaniola (Dominican Republic) based on 34 samples collected by the senior author in December–January 1969/70. New species are Entophlyctis obscura, Phlyctochytrium parasitans, P. mucosum, Blyttiomyces harderi, Rhizophlyctis tropicalis, Chytriomyces multioperculatus.Supported in part by N. S. F. Grant GB 3333. It was originally hoped to collect species of Physoderma on Hispaniola but none was found during the few days available for exploration.I am indebted to Prof. I. Bonnelly de Calventi, Director, Inst. de Biologia marina, Univ. Autonoma de Santo Domingo, for many courtesies.     

Inferring the evolutionary history of Drosophila americana and Drosophila novamexicana using a multilocus approach and the influence of chromosomal rearrangements in single gene analyses

The evolutionary history of closely related organisms can prove sometimes difficult to infer. Hybridization and incomplete lineage sorting are the main concerns; however, genome rearrangements can also influence the outcome of analyses based on nuclear sequences. In the present study, DNA sequences from 12 nuclear genes, for which the approximate chromosomal locations are known, have been used to estimate the evolutionary history of two forms of Drosophila americana ( Drosophila   americana americana and Drosophila americana texana ) and Drosophila novamexicana ( virilis group of species). The phylogenetic analysis of the combined data set resulted in a phylogeny showing reciprocal monophyly for D. novamexicana and D. americana . Single gene analyses, however, resulted in incongruent phylogenies influenced by chromosomal rearrangements. Genetic differentiation estimates indicated a significant differentiation between the two species for all genes. Within D. americana , however, there is no evidence for differentiation between the chromosomal forms except at genes located near the X/4 fusion and Xc inversion breakpoint. Thus, the specific status of D. americana and D. novamexicana is confirmed, but there is no overall evidence for genetic differentiation between D. a. americana and D. a. texana , not supporting a subspecific status. Based on levels of allele and nucleotide diversity found in the strains used, it is proposed that D. americana has had a stable, large population during the recent past while D. novamexicana has speciated from a peripheral southwestern population having had an ancestral small effective population size. The influence of chromosomal rearrangements in single gene analyses is also examined.     

Vocalizations and relationships of Brown Creepers Certhia americana: a taxonomic mystery

Two taxa of creepers ( Certhia spp.) occur in Europe, C. familiaris and its sibling species C. brachydactyla. The North American Brown Creeper was considered a close relative of C. brachydactyla by one author, a close relative of or conspecific with C familiaris by others, and more recently as a distinct species, C. americana, by the American Ornithologists' Union. Songs of these three creepers are comprised mostly of social calls which are derived from begging calls. Sequence of syllables (syntax) is very conservative in songs of European population of C. familiaris and C. brachydactyla. In contrast, syntax in songs of western North American C. americana is highly variable; however, syllable morphology and syntax in some populations or individuals within populations is remarkably similar to songs of C. brachydactyla, notably from France and Spain. Two social calls and sleeping behaviour of C. americana are also similar to those of C. brachydactyla. Either C. americana and C. brachydactyla are close relatives or they have characters retained from the ancestor common to all three species whereas those in extant C familiaris have diverged.     

Relationships and evolution of the North African geckos,Geckonia and Tarentola (Reptilia: Gekkonidae), based on mitochondrial and nuclear DNA sequences

Mitochondrial (cytochrome b and 12S rRNA) and nuclear (c-mos) genes, analyzed by a variety of methods, indicate that the distinctive northwest African gecko Geckonia chazaliae is a member of the Tarentola clade, being most closely related to the species of the western Canary and Cape Verde islands. Relationships in Tarentola as a whole are as follows: (T. americana ((T. mauritanica, T. angustimentalis) ((T. deserti, T. boehmei) ((T. b. boettgeri-South (T. b. boettgeri-North (T. b. bischoffi, T. b. hierrensis))) ((T. annularis, T. ephippiata) (Geckonia, T. delalandii, T. gomerensis, Cape Verde species)))))); nearly all nodes have high bootstrap support. Results confirm that T. americana of Cuba and the Bahamas separated at the most basal dichotomy of the phylogeny and give no positive support for the monophyly of the subgenera Tarentola s. str. and Makariogecko. The latter includes Geckonia and the subgenus Sahelogecko. Continental Tarentola appear to have invaded the Sahara desert from its northern edge. They have also colonized groups of Atlantic islands five times: a single invasion of the West Indies and three of the Canary islands, one of which then went on to invade the Cape Verde archipelago. The phylogeny corroborates anatomical evidence that the ground-dwelling Geckonia had a climbing ancestry, something that is paralleled in some southern African terrestrial gekkonids related to Pachydactylus. Distinctive derived features of Geckonia occur in other gekkonids that are ground dwelling in arid habitats and may be functionally related to this environment. The evolution of such features indicates that, although Tarentola is generally very uniform and may have been so for over 10 million years, this is not due to any overwhelming phylogenetic constraint. G. chazaliae should be included in Tarentola, as Tarentola chazaliae.     

Extinction and biogeography in the Caribbean: new evidence from a fossil riodinid butterfly in Dominican amber

We describe a new species of extinct riodinid butterfly, Voltinia dramba, from Oligo-Miocene Dominican amber (15-25 Myr ago). This appears to be the first butterfly to be taxonomically described from amber, and the first adult riodinid fossil. The series of five specimens represents probably the best-preserved fossil record for any lepidopteran. The phenomenon of extant Voltinia females ovipositing on arboreal epiphytes probably explains the discovery of multiple female V. dramba specimens in amber. Voltinia dramba appears to be one of many extinct butterfly species on Hispaniola. The northwestern Mexican distribution of the explicitly hypothesized sister species, the extant V. danforthi, supports the hypothesis that V. dramba reached Hispaniola by the 'proto-Greater Antillean arc', dating the divergence of V. dramba and V. danforthi to 40-50 Myr ago. This date is contemporaneous with the oldest known butterfly fossils, and implies a more ancient date of origin for many of the higher-level butterfly taxa than is often conceded.     

New records of Caribbomerus from Hispaniola and Dominica with redescription of C. elongatus (Fisher) and a key to species of the genus in the West Indies (Coleoptera, Cerambycidae, Cerambycinae, Graciliini)

Three species of Caribbomerus Vitali are newly recorded for the Dominican Republic: Caribbomerus decoratus (Zayas), Caribbomerus elongatus (Fisher), and Caribbomerus asperatus (Fisher). The first two also represent first records for Hispaniola. Caribbomerus elongatus (Fisher) is redescribed based on additional material, including the first known males. Caribbomerus similis (Fisher) is newly recorded for Dominica. A key to the species of the genus from the West Indies is provided.     

Pereskia marcanoi,a new species of Cactaceae from Hispaniola

Pereskia marcanoi is newly described from the rocky hillsides of Cerro San Francisco (Bánica), western Dominican Republic. With three other species from Hispaniola and Cuba, this new taxon forms a unique group of functionally dioeciousPereskia species native to the West Indies. Some important diagnostic characters of the members of this group are contrasted in key form.     

To which genus of Asteraceae does Liabum oblanceolatum belong? Vegetative characters have the answer

The West Indian species Liabum oblanceolatum Urb. & Ekman was established on the basis of sterile young specimens represented by acaulescent herbs with rosulate leaves. However, these specimens have important traits that do not correspond to Liabum Adans. More than 90 genera of Asteraceae occur in Hispaniola (= Santo Domingo), but only 14 of them include species represented by acaulescent herbs with rosulate or grouped leaves at the base of the stem. From these genera, Chaptalia Vent. and Liabum are the most similar to the types of L. oblanceolatum . Habit, leaf arrangement, lamina shape, leaf margin, leaf surface, leaf margin intrasection, leaf venation, leaf pubescence, leaf trichomes, stomata and upper surface leaf cuticle were analysed in the type specimens of L. oblanceolatum and in species of Chaptalia and Liabum of Hispaniola. The vegetative trichomes are described in detail. The analysis reveals that the type specimens of L. oblanceolatum fit with all the vegetative traits of Chaptalia angustata Urb. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 479–486.     

The DAIBAM MITE element is involved in the origin of one fixed and two polymorphic Drosophila virilis phylad inversions

Chromosomal inversions can originate from breakage and repair by non-homologous end-joining. Nevertheless, they can also originate from ectopic recombination between transposable elements located on the same chromosome inserted in opposite orientations. Here, we show that a MITE element (DAIBAM), previously involved in the origin of one Drosophila americana polymorphic inversion, is also involved in the origin of one fixed inversion between D. virilis and D. americana and another D. americana polymorphic inversion. Therefore, DAIBAM is responsible for at least 20% of the chromosomal rearrangements that are observed within and between species of the virilis phylad (D. virilis, D. lummei, D. novamexicana and D. americana), having thus played a significant role in the chromosomal evolution of this group of closely related species.     

Further studies on proctolin analogues modified in position 2 of the peptide chain and their influence on heart-beat frequency of insects

Seven proctolin analogues (I-VII) modified in position 2 of the peptide chain by Phe (p-guanidino) (I), Phe (p-OEt) (II), Tyr (3'-NH2) (III), Tyr (3'-NO2) (IV), Afb (p-OH) (V) (Afb = 3-amino-4-phenyl-L-butyric acid), Afb (p-NH2) (VI), Afb (p-NO2) (VII), and the tetrapeptide Tyr (3'-NH2)-Leu-Pro-Thr (VIII) were synthesized by the classic liquid-phase method. The biological effects of the peptides were investigated in cardioexcitatory tests on two insect species, the cockroach Periplaneta americana L., and the yellow mealworm, Tenebrio molitor L. Within physiological concentrations (10(-9)-10(-7) M) peptides II, III, and IV stimulated the heart action of P. americana like proctolin itself. Under identical conditions, in the case of T. molitor, only peptide III showed cardiostimulatory properties, whereas other compounds (including II and IV) were inactive at concentrations up to 10(-7) M. Results reported here reflect, with reference to the analogues I-VII, selective recognition of receptors on myocardium of both insect species. The tetrapeptide VIII revealed a weak deacceleratory effect on P. americana and T. molitor heart action.