Showing papers on "Genus published in 1981"
TL;DR: A formal infrageneric classification for the genus Helianthus was derived using phenetic, cladistic and biosystematic procedures and the 49 species were placed into four sections and seven series.
Abstract: Summary A formal infrageneric classification for the genus Helianthus is presented. The classification was derived using phenetic, cladistic and biosystematic procedures. The 49 species of Helianthus are placed into four sections and seven series.
204 citations
TL;DR: In each species of the Bambara invisibilis group on Sri Lanka the form of the sperm is highly coadapted structurally with that of the spermatheca, suggesting an important functional morphological relationship between these complementary male and female reproductive structures.
Abstract: Sperm and spermathecae in minute beetles that inhabit the island of Sri Lanka (Ceylon) show diagnostic differences in form among closely related species and are highly coadapted morphologically in each species. Complementary morphological relationships between sperm and spermathecae are previously unreported in insects and are of unusual evolutionary interest. Beetles belonging to the genus Bambara (Coleoptera: Ptiliidae, commonly known as featherwing beetles) are less than a millimeter long and live in decaying litter on the forest floor in tropical and subtropical regions of the world. The beetles are often abundant but most species are still unnamed, including seven of the eight species of the Bambara invisibilis group in Sri Lanka with which this report is concerned. The eight species are closely related and remarkably similar externally (Dybas, in prep.), but they can be separated by constant differences in the form of the spermatheca (sperm storage organ) of the female. The taxonomic usefulness of this structure has also been demonstrated in other genera of the family (Besuchet and Sundt, 1971). We now report that each species in the invisibilis group on Sri Lanka differs from all others in external morphology of the sperm as well. Differences in sperm of closely related species of animals have been reported previously (Friend, 1936; Hirth, 1960; McFarlane, 1963; Forman, 1968; Genoways, 1973; Linzey and Layne, 1974) but the differences that characterize the sperm of Bambara species on Sri Lanka are more striking than any previously discovered. Moreover, in each species the form of the sperm is highly coadapted structurally with that of the spermatheca, suggesting an important functional morphological relationship between these complementary male and female reproductive structures.
146 citations
01 Jan 1981
142 citations
TL;DR: The three subgenera recognized within the genus Acacia are outlined and the global distribution of each is indicated and it is suggested that the ancestral members of the genus were climbers or lianes.
Abstract: The three subgenera recognized within the genus Acacia are outlined and the global distribution of each is indicated. The differences between the subgenera and the degree of relationship and levels of specialization are discussed briefly. It is suggested that the ancestral members of the genus were climbers or lianes. Past geological events considered likely to have influenced the distribution of the Acacia species in Africa are outlined. The number of species recorded from each African country is tabulated and the distribution and concentration of species within the genus Acacia as a whole and within each subgenus in Africa are illustrated. The highest concentrations of species within each subgenus occur in tropical east and south-east Africa. The distribution o f species within some o f the individual African countries and possible affinities are discussed and attention is drawn to the main centres of endemism. The distribution of the African species is correlated with the major phytogeographical regions recognized on the continent. The relationships between the African and the American, Madagascan, Indian and Australian Acacia species are discussed briefly.
98 citations
TL;DR: A revision of the species in the genus Pityophthorus Eichhoff in North and Central America is presented in this paper, which contains 220 species in North-and Central-America.
Abstract: A revision of the species in the genus Pityophthorus Eichhoff in North and Central America is presented. The limits of Pityophthorus are expanded to include the species previously placed in Gnatholeptus Blackman. This unit is maintained as a subgenus. One additional subgenus is described, Hypopityophthorus, for P. debilis Wood and P. inops Wood. The genus contains 220 species in North and Central America. The principal subgenus Pityophthorus is divided into 47 species groups. New species are: micans (Mexico), sapineus (Mexico), miniatus (Honduras, Guatemala, and Mexico), pubifrons (Mexico), and acceptus (British Columbia, Wyoming). New synonymy is proposed as follows: P. deletus LeConte (= P. dolus Wood); P. exquisitus (Blackman) n. comb. (= P. inceptis Wood); P. intextus (= P. ornatus Blackman and P. limatus Wood); P. balsameus Blackman (= P. angustus Blackman) and P. indigens Wood (= P. irritans Schedl). Five species are given new status as subspecies: P. tuberculatus Eichhoff as a subsp. of P. pulchellus Eichhoff; P. subopacus Blackman as a subsp. of P. segnis Blackman; P. bellus Blackman as a subsp. of P. confusus Blandford; P. agnatus Blackman as a subsp. of P. confertus Swaine, and P. aurulentus Bright as a subsp. of P. murrayanae Blackman.The monograph includes an historical review, a discussion of diagnostic characters, and a discussion of the general biology of species in the genus. Keys to subgenera, species groups, and species are provided. Each species is described and many are illustrated, and all known bionomic and distributional data are included. Distribution records of many species are mapped.
75 citations
TL;DR: Eight of the common species of the genus Myriophyllum are found to exhibit sufficient phenotypic plasticity to account for most if not all the taxonomic problems encountered.
Abstract: Thirteen species of the genus Myriophyllum are found in North America; ten are native, three have been introduced. A key to the species is provided and previous conflicting taxonomic treatments are assessed. The possibility of a polyploid series involving four species is considered and dismissed. Eight of the common species are found to exhibit sufficient phenotypic plasticity to account for most if not all the taxonomic problems encountered.
74 citations
01 Jan 1981
64 citations
63 citations
TL;DR: A re‐examination of all the known species of Geonemertes has shown that two major groups can be distinguished on the basis of morphological characters, and a key to the terrestrial, brackish‐water and marine nemertean species described in the present paper is provided.
Abstract: A new genus of monostiliferous hoplonemerteans, Pantinonemertes gen. nov., provides evidence for the separate evolution of terrestrial nemerteans. The genus is established for two new species found in Australia, P. enalios sp. nov., an intertidal form, and P. winsori sp. nov., which lives in fallen timber in the supralittoral brackish water regions of mangrove swamps. One only of the known species of land nemerteans, Geonemertes agricola from Bermuda, closely resembles these two species morphologically and is transferred to the new genus as Pantinonemertes agricola.
A re-examination of all the known species of Geonemertes has shown that two major groups can be distinguished on the basis of morphological characters. In one group the rhynchocoel musculature is in two distinct layers, a frontal organ is present, the mid-dorsal blood vessel has a single vascular plug, and the flame cells are binucleate and reinforced with cuticular support bars. It comprises the genus Pantinonemertes gen, nov, and the Pelaensis or Indopacific group of terrestrial nemerteans, for which the generic name Geonemertes is retained. In the second major group the rhynchocoel musculature is composed of interwoven longitudinal and circular fibres, there is no frontal organ, the mid-dorsal blood vessel bears two vascular plugs, and the flame cells are mononucleate and lack support bars. Five genera, three of which are new, are distinguished in this group. Australian species are united in the genus Argonemertes gen. nov., and New Zealand forms comprise the genus Antiponemertes gen. nov., while Acteonemertes bathamae from New Zealand and the Auckland and Ocean Islands remains in a separate genus. Geonemertes nightingaleensis is transferred to a new genus, Katechonemertes gen. nov., and for Geonemertes chalicophora a previously used generic name, Leptonemertes, is adopted.
A key to the terrestrial, brackish-water and marine nemertean species described in the present paper is provided.
62 citations
Journal Article•
TL;DR: Examination of the historical records shows that the very common epithet “ astraea ” is invalid and cannot be used for any Stephanodiscus species, and the validity of S. niagarae Ehr.
TL;DR: It has become clear that the two forms of Botrylloides mentioned above are quite distinct from each other, and the authors are now facing a taxonomic problem to determine by which of these two forms Botryllid violaceus should be represented.
Journal Article•
TL;DR: Three new species are described and one, P. damonidaensis, presents a character unique within the family Phrynidae : three tibial segments in le g IV instead of four.
Abstract: rcharacterization of the three families of amblypygids which lack pulvilli in the tarsi of their ambulatory legs . The gensus Phrynus has been found to occur only in the Americas and a redefinition of th e Phrynidae is given . Of the 24 species of Phyrnus described for the Americas, 12 species are considere d as valid and redescribed . The three species described by Franganillo, Phrynus pinarensis, P . viridescen s and P . rangelensis are considered species Incertae Sedis . Three new species are described ; one, P. damonidaensis, presents a character unique within the family Phrynidae : three tibial segments in le g IV instead of four . Five new synonymies are recognized . Natural history data are presented for som e of the species of Phrynus .
TL;DR: It is suggested, that each group has its closest affinities with Old World genera and that this indicates that the diversification of the marantaceous stock was far–reaching already before the Old and the New World became effectively isolated.
Abstract: The delimitation of the neotropical genera of the Marantaceae has been revised, using evidence mainly from the morphology of inflorescences and flowers. It is concluded that the generic concepts of Schumann in “Das Pflanzenreich”, often questioned by 20th century American authors, are essentially sound, but that his grouping of the genera into two tribes is quite artificial. Main deviations from the treatment of Schumann are the rearrangement of the genera, somewhat different stress on diagnostic characters and a much narrower concept of the genus Myrosma. A new genus, Koernickanthe is proposed for the long known species Maranta orbiculata (Koern.) Schum. The genera are arranged into informal groups and the groups and genera recognized are: Maranta group (Maranta L., Monophyllanthe Schum.), Myrosma group (Myrosma L. f., Saranthe (Regel et Koern.) Eichl., Hylaeanthe Jonker et Jonker, Ctenanthe Eichl., Stromanthe Sond.), Calathea group (Calathea G. F. W. Meyer, lschnosiphon Koern., Pleiostachya Schum.), Monotagma group (Monotagma Schum., Koernickanthe gen. nov.) and Thalia“group”(Thalia L.). It is suggested, that each group has its closest affinities with Old World genera and that this indicates that the diversification of the marantaceous stock was far–reaching already before the Old and the New World became effectively isolated. It is further suggested that the early diversification of the family took place in Africa, the flora of which, although poor in species, is morphologically very diverse. Two new combinations are made, viz. Stromanthe stromanthoides (Macbr.) Anderss. and Koernickanthe orbiculata (Koern.) Anderss.
TL;DR: Myrceugenia is a mainly temperate South American genus with two species on the Juan Fernandez Islands, 12 in central and southern Chile and adjacent Argentina, and 25 in the highlands of southeastern Brazil and adjacent regions as discussed by the authors.
Abstract: Myrceugenia is a mainly temperate South American genus with two species on the Juan Fernandez Islands, 12 in central and southern Chile and adjacent Argentina, and 25 in the highlands of southeastern Brazil and adjacent regions. The continental populations are separated by about 1000 km. Numerical cladistic procedures based on the criteria of parsimony, compatible characters and a combination of compatible characters and character correlation are used to deduce hypothetical phylogenetic undirected trees. These indicate that 3–8 groups of species bridge the continent of South America. An explanation of how the distribution of the genus could have come about is given based on: 1) the above mentioned numerical analyses, 2) the ecology of the species, 3) the distribution of other plant genera, and 4) theories of the geologic and climatic history of southern South America. Myrceugenia is hypothesized to have grown continuously across South America during the early Tertiary and to have become divided into eastern and western populations probably during the Miocene.
TL;DR: Electrophoretic analysis of 19 biochemical loci was used to investigate relationships among six species of crayfish inhabiting the Savannah River Plant near Aiken, South Carolina, finding H in decapod crustaceans is low compared to that of other organisms.
Abstract: Electrophoretic analysis of 19 biochemical loci was used to investigate relationships among six species of crayfish inhabiting the Savannah River Plant near Aiken, South Carolina. One species of the genus Cambarus (C. latimanus) and five species of the genus Procambarus (P. ranei. P. pubescens, P. hirsutus, P. acutus, P. troglodytes) were studied. Seven of 19 loci were polymorphic in at least one species while 12 loci were consistently monomorphic in all species. The mean heterozygosity (H) for all species was 0.016?0.01. Nei's identity values (I) were calculated for all species pairs. The average J between Procambarus species was 0.78 ?0.1 and the range was 0.63 to 0.89. The average J between C. latimanus and the Procambarus species was 0.51 ? 0.04. As shown in this and other studies, H in decapod crustaceans is low compared to that of other organisms..
TL;DR: The genus Lychnophora is remarkable for its morphological adaptation to fire and xeric habitats and for its elaborate speciation in a limited geographical area.
Abstract: Distributionmaps, specimen citations, synonymies, descriptions, taxonomic commentaries and a key are provided for the 11 species ofLychnophora Mart. (Vernonieae: Compositae). One new species,Lychnophora diamantinana Coile & Jones, is described and several are excluded from the genus. Chromosome counts ofn = 17 for four species ofLychnophora are reported together with field observations for many species. The genus is remarkable for its morphological adaptation to fire and xeric habitats and for its elaborate speciation in a limited geographical area.
TL;DR: The present investigation clarifies generic relationships of Spilanthes in relation to Acmella, presents the taxonomy of the six species of Spi- lanthes, and develops a phylogenetic reconstruction of these species using cladistic methods.
Abstract: Spilanthes is widespread throughout the New and Old World tropics. Morphological and chromosomal evidence supports separation of the genus into two genera, Spilanthes and Acmella, which can be distinguished by at least eight morpho- logical characters and by distinctive basic chromosome numbers. Studies of other genera within the Heliantheae suggest that both Spilanthes and Acmella are allied to Salmea in the Verbesininae. Spilanthes is here recognized as comprising six species distributed primarily in sandy soils of South America, the West Indies, northern Australia, Malaysia, and central and western Africa. A phylogenetic reconstruction employing cladistic methods suggests that the New World species, S. leiocarpa, S. nervosa, S. paraguayensis, and S. urens, are more closely allied to each other than to the Old World species. The cladistic analysis further suggests a closer relationship between the Australo-Malaysian S. anactina and the New World species than with S. costata, a species restricted to central and western tropical Africa. Spilanthes Jacq. (sensu Moore 1907) is primarily a weedy genus of 30- 40 species of Compositae (Heliantheae) in the New and Old World trop- ics. The genus has been traditionally divided into two sections, Spilanthes and Acmella Rich. (de Candolle 1836; Moore 1907). Morphological and chromosomal studies (Jansen 1979; Jansen and Stuessy 1980) suggest that these sections merit recognition at the generic level. From this view- point Acmella contains approximately 30 species and is currently being revised (Jansen in progress). Spilanthes is here recognized as comprising six species distributed primarily in sandy soils of South America, the West Indies, northern Australia, Malaysia, and central and western Af- rica. The present investigation clarifies generic relationships of Spilanthes in relation to Acmella, presents the taxonomy of the six species of Spi- lanthes, and develops a phylogenetic reconstruction of these species using
TL;DR: It is concluded that there is one multivariate species encompassing the tintinnid genus Ptychocylis, by priority to be named P. obtusa, and that other means than the lorica alone must be used to distinguish species in this genus.
Abstract: A total of 121 photographs was made of specimens in the tintinnid genus Ptychocylis, col- lected in the vicinity of TromsO, northern Norway. Selections are shown from these photographs to il- lustrate variations that occurred. In addition, detailed measurements were undertaken of 165 specimens from the same samples. From all of these and from the literature it is concluded that it is not feasible on the basis of lorica shape to distinguish among the following described species: P. acuta, P. arclica, P. basicurvaia, P. cylindrica. P. drygalskii, P. glatialis and P. obtusa. Further- more, some of the illustrated forms do not correspond to any descriptions found in the literature. It is concluded either that there is one multivariate species encompassing the above list, by priority to be named P. obtusa, or else that other means than the lorica alone must be used to distinguish species in this genus.
TL;DR: The "primitive" five digited, lacertiform ocellatus species group has a vast continuous range, with nine similar species, some of which may be species complexes.
Abstract: Sixteen species of Chalcides can be distinguished by means of morphological and geographical criteria. There are five species groups. Three of the groups are relictual, contain few, distinctive species, and show an advanced stage of the scincid trend toward slimmer habitus and limb reduction. The "primitive" five digited, lacertiform ocellatus species group has a vast continuous range, with nine similar species, some of which may be species complexes. A key to currently recognizable species is given.
Journal Article•
TL;DR: Two new species of fishes, T. nanuss andT.
Abstract: A recent (1979) expedition to the Chagos Archipelago resulted in the collection of about 40 new taxa of fishes. A new genus,Trimmatom, and two new species,T. nanus andT. offucius, are described here. The new genus is characterized by having all pelvic-fin rays simple (unbranched), a scaleless body, no head pores, a wide gill opening extending anteroventrally to below the eye, and hypurals 1 and 2 fused to the complex formed by the fusion of the ural centrum and hypurals 3 and 4.T. nanuss andT. offucius are differentiated on the basis of fin ray counts and colour pattern.T. nanus is the smallest vertebrate yet to be described. Mature females with ovaries full of eggs are 8–10 mm in standard length.
TL;DR: The endemic Australian genus Drepanotermes is revised, and data is provided on the distribution, habitat, nest structure, food, flight, inquilines, affinities and sympatric associations of the individual species.
Abstract: The endemic Australian genus Drepanotermes is revised Seventeen new species are described: D Acicularis, D Barrett, D Basidens, D Bellator, D Brevis, D Calabyi, D columellaris, D corax, D crassidens, D dibolia, D diversicolor, D gayi, D harnulus, D hilli, D invasor, D paradoxus and D phoenix, D clarki (Hill), D daliensis Hill, D perniger (Froggatt), D rubriceps (Froggatt), D seprentrionalis Hill and D tamminensis (Hill) are redescribed, from all castes if known D magnificus (Mjoberg) is regarded as a nomen dubium and D rubriceps opacus (Hill) as a nomen nudum; lectotype soldiers are designated for D daliensis, D perniger, D silvestrii Hill regarded as a synonym of D rubriceps, D septentrionalis and D tamminensis The general biology of Drepanotermes is summarized, and data are provided on the distribution, habitat, nest structure, food, flight, inquilines, affinities and sympatric associations of the individual species
TL;DR: The type-genus Eurycope is revised, and three new genera are proposed to contain some of the species removed from it, permitting more precise generic placement of other species.
Abstract: Most of the genera in the important deep-sea isopod family Eurycopidae need revision. In this paper, the type-genus Eurycope is revised, and three new genera (Disconectes, Tytthocope, and Belonectes) are proposed to contain some of the species removed from it. The new genera are based on redescribed type-species, permitting more precise generic placement of other species. New records are given for Disconectes phalangium and Belonectesparvus.
01 Jan 1981