Unusual kinematics and jaw morphology associated with piscivory in the poeciliid,Belonesox belizanus

Piscivory in fishes is often associated with the evolution of highly elongate jaws that achieve a large mouth opening, or gape. Belonesox belizanus, the pike killifish, has independently evolved this morphology, which is derived from short-jawed poeciliids within the Cyprinodontiformes. Using kinematic analysis of high-speed video footage, we observed a novel aspect of the elongate jaws of Belonesox; the premaxilla rotates dorsally during mouth opening, while the lower jaw rotates ventrally. Anatomical study revealed that this unusual motion is facilitated by the architecture of the premaxillomandibular ligament, prominent within cyprinodontiforms. In Belonesox, it allows force to be transferred from the lower jaw directly to the premaxilla, thereby causing it to rotate dorsally. This dorsal rotation of the premaxilla appears to be assisted by a mediolateral twisting of the maxilla during jaw opening. Twisting maxillae are found in members of the group such as Fundulus, but are lost in Gambusia. Models revealed that elongate jaws partially account for the enlarged gape, but enhanced rotation at the quadrato-mandibular joint was equally important. The large gape is therefore created by: (i) the convergent evolution of elongate jaws; (ii) enhanced jaw rotation, facilitated by loss of a characteristic cyprinodontiform trait, the lip membrane; and (iii) premaxilla rotation in a novel direction, facilitated by the retention and co-option of additional cyprinodontiform traits, the premaxillomandibular ligament and a twisting maxilla.     

Mitochondrial DNA sequence variation of four <Emphasis Type="Italic">Saccharina</Emphasis> species (Laminariales,Phaeophyceae) growing in Japan

The complete mitochondrial DNA (mtDNA) was sequenced for four Saccharina species including three varieties of Saccharina japonica in Hokkaido: S. japonica; S. japonica var. religiosa; S. japonica var. ochotensis; S. japonica var. diabolica; Saccharina longipedalis; Saccharina angustata; and Saccharina coriacea. Furthermore, the structure and the sequence were compared among them. The total nucleotide length was 37,500–37,657 bp. All mtDNAs were mapped and no differences in the organization of the coding region were found. From the total alignment of S. japonica including the three varieties and S. longipedalis, nucleotide substitutions were detected at 68 sites, and a nucleotide insertion/deletion was detected at one site on rps19 for the whole genome. Variable regions useful for varieties distinction of S. japonica were trnI, trnM, rps19, ORF41, and seven spacers. The pairwise distance between S. japonica, S. angustata, and S. coraiacea was 0.000–0.116. Sequencing comparisons of rps7, rps11, rpl5, and tatC were thought to be useful tools for discrimination and phylogenetic analysis of Saccharina species having similar morphologies.     

Panbiogeographical analysis of the shark genus Rhizoprionodon (Chondrichthyes,Carcharhiniformes, Carcharhinidae)

The distributional patterns of the seven species of Rhizoprionodon were analysed using the panbiogeographical method of track analysis. The individual tracks of Rhizoprionodon suggest that the genus is mainly an Indian–Atlantic Ocean group. Five generalized tracks were found: (1) Caribbean, defined by R. porosus and R. terraenovae; (2) eastern coast of South America, defined by R. porosus and R. lalandei; (3) Indian Ocean, defined by R. acutus and R. oligolinx; (4) north‐western Australia, defined by R. acutus, R. oligolinx and R. taylori; (5) north‐north‐eastern Australia, defined by R. acutus and R. taylori. Only R. longurio was not included in any generalized track, and its distribution is restricted to the eastern Pacific Ocean. Two biogeographical nodes were found at the intersection of the generalized tracks 1 and 2 (Caribbean Sea) and generalized tracks 4 and 5 (north Australia). The generalized tracks overlap with those found in several unrelated marine taxa. Overall, the generalized tracks are associated with warm currents. The biogeographical nodes found (Caribbean and Australian) are coincident with the global distribution of mangroves.     

Notes on some plant-inhabiting fungi collected from the Nansei Islands (1)

In the course of a survey on plant diseases and their pathogenic fungi in the Nansei Islands, some noteworthy fungi were collected. Among them, four fungi newly found in Japan were described with some mycological and pathological notes. These species are Septoria gardeniae Savelli, causing circular leaf spot of Gardenia; Phyllosticta cordylinophila Young apud Stevens, causing brown leaf spot of Cordyline; Phyllosticta drummondii Vanef et van der Aa, causing brown needle blight of Araucaria; and Phyllachora minuta Hennings, causing tar spot of Hibiscus.     

Purification,characterisation and amino acid composition of the putative moult-inhibiting hormone (MIH) ofCarcinus maenas (Crustacea,Decapoda)

Summary Using a Y-organ in vitro assay to measure repression of ecdysteroid synthesis in the presence of putative moult-inhibiting hormone (MIH), in conjunction with HPLC separation of sinus gland neuropeptides ofCarcinus maenas, it was found that both the hyperglycemic hormone (CHH) and a novel peptide (argued to represent the MIH) inhibited ecdysteroid synthesis. The latter was purified to homogeneity, and amino acid analysis showed that it is a 61 residue peptide (minimum molecular mass 7,200 Da) with the following amino acid composition: Asx₉; Thr₂; Ser₂; Glx₇; Pro₁; Gly₄; Ala₂; 1/2 Cys₄; Val₄; Met₁; Ile₃; Leu₅; Tyr₁; Phe₃; His₃; Trp₂; Lys₂; Arg₆. The N-terminus appears to be blocked. MIH is at least 20 times more potent than CHH in repressing ecdysteroid synthesis and is active at concentrations of less than 250 pmol/l. There may be structural similarities between CHH and MIH, howeve, MIH displays no CHH radioimmunoreactivity or hyperglycemic activity. The physiological significance of CHH in controlling ecdysteroid titres is not known.Abbreviations CHH hyperglycemic hormone - MIH moult inhibiting hormone - PAGE polyacrylamide gel electrophoresis - RIA radioimmunoassay - SDS sodium dodecyl sulfate - SG smus gland(s) - SGE sinus gland equivalent - TFA trifluoroacetic acid     

Seasonal Changes in Lorica Sizes and the Species of Tintinnida in the New York Bight*

SYNOPSIS. Tintinnida of the New York Bight (a bend in the coastline) were identified during the 1-year period August 1973–August 1974. Recurring genera included Stenosemella and Tintinnopsis; seasonal genera were mainly the hyaline Favella, Metacylis, and Helicostomella; exotic or unusual genera included Parafavella and Ptychocylis. Large size differences in loricae were found seasonally, related apparently, to water temperature.     

Revision of fossil hominid jaws from the plio/pleistocene of hadar,in ethiopia including a new species of the genusHomo (hominoidea: homininae)

The assignment of fossil hominoid jaws from the Plio/Pleistocene of Hadar to a single genus,Australopithecus Dart, 1925, is a misnomer. They are morphologically unrestricted to and inconsistent with the diagnosis and evolutionary trend ofAustralopithecus. The morphological pattern of four large jaws is indeed australopithecine and similar toA. africanus Dart, 1925, but six small jaws reveal a pre-habilis stage of dental development early in theHomo lineage. On the basis of their unique hominine dentition, they are reinterpreted as representing a new species,Homo antiquus n.sp.     

The jaw apparatuses of Cretaceous Phylloceratina (Ammonoidea)

The jaw apparatuses of two species of Late Cretaceous Phylloceratina (Ammonoidea), Hypophylloceras subramosum and Phyllopachyceras ezoensis, are described on the basis of well‐preserved in situ material from Hokkaido, Japan. Gross morphological and X‐ray CT observations reveal that the upper and lower jaws of the two species are essentially similar in their overall structure. Their upper jaws consist of a shorter outer lamella and a pair of larger, wing‐like inner lamellae that become narrower and join together in the anterior portion, as in those of other ammonoids. The upper jaws of the two phylloceratid species are, however, distinguishable from those of other known ammonoids by the presence of a thick, arrowhead‐shaped calcified rostral tip. The lower jaws of the two species consist of a short, reduced inner lamella and a large, gently convex outer lamella covered with a thin calcareous layer, the features of which are common with the rhynchaptychus‐type lower jaws of the Cretaceous Lytoceratina. In the presence of a sharply pointed, thick calcareous tip on upper and lower jaws, the jaw apparatuses of the Phylloceratina resemble those of modern and fossil nautilids, suggesting that they were developed to serve a scavenging predatory feeding habit in deeper marine environments. This and other studies demonstrate that at least some Mesozoic rhyncholites and conchorhynchs are attributable to the Phylloceratina and Lytoceratina.     

PHYTOCHEMICAL STUDIES IN THE FAMILY MALVACEAE. I. COMPARISON OF ESSENTIAL OILS OF SIX SPECIES BY GAS-LIQUID CHROMATOGRAPHY

When the chemical constitution of the essential oils of six species within three genera of the family Malvaceae were investigated, the essential oils of Gossypium hirsutum L. and Cienfuegosia rosei Fryxell were found to contain 67.0 % and 58.2 % hydrocarbons, respectively. Those of Hibiscus lasiocarpus (Cav.) and Callirhoe involucrata (Nutt.) Gray contained equal percentages of hydrocarbons (14 %), but that of Cienfuegosia drummondii (A. Gray) Lewt. contained only 2.9 % hydrocarbons. Beta-bisabolol was the major oxygenated component in G. hirsutum (13.7 %), Hibiscus militaris (Cav.) (55.0 %), and Hibiscus lasiocarpus (32.6 %), but the major constituents in the essential oil of C. involucrata were myrtenal (32.0 %) and trans-2-cis-6-nonadienal (12.0 %), and the major oxygenated component in C. rosei was an unknown sesquiterpene alcohol (17.4 %) with chemical and physical properties resembling those of beta-bisabolol. The concentration of total oil was 150.0 ppm in G. hirsutum; 50.0 ppm in H. militaris; 46.3 ppm in C. rosei; 41.0 ppm in H. lasiocarpus; 25. 4 ppm in C. drummondii; and 10.0 ppm in C. involucrata, all based on wet weight.     

Linkage relationships of 19 protein coding genes in watermelon

Summary Segregation of seed proteins and isozymes was analysed in two Citrullus crosses. In the first cross an F1 hybrid between C. lanatus and the wild species C. colocynthis was used as a female parent in a backcross to C. lanatus. In this interspecific cross the segregation of 17 markers was analysed. Four linkage groups were identified: linkage group 1 includes the genes Est-2, Skdh-2, Tpi-1, Fdp-1, Sod-1 and Prx-1; linkage group 2 — Got-1, Got-2 and Sp-4; linkage group 3 — Pgm-1 and Gdh-2; linkage group 4 with Pgi-1 and Pgi-2. In the second cross an F1 hybrid between two C. colocynthis accessions was backcrossed to one of its parents. Seven loci were scored and no new linkages were found.     

Microstructure and mineralogy of the outer calcareous layer in the lower jaws of Cretaceous Tetragonitoidea and Desmoceratoidea (Ammonoidea)

Tanabe, K., Landman, N.H. & Kruta, I. 2011: Microstructure and mineralogy of the outer calcareous layer in the lower jaws of Cretaceous Tetragonitoidea and Desmoceratoidea (Ammonoidea). Lethaia, Vol. 45, pp. 191–199. Based on the differences in their relative size, overall shape, structure and the degree of development of an outer calcified covering, lower jaws of the Ammonoidea have been classified into four morphotypes: normal, anaptychus, aptychus and rhynchaptychus types. However, detailed microstructural and mineralogical comparison of these morphotypes has not yet been addressed. This article documents the results of SEM and XRD observations of the lower jaws of three Late Cretaceous ammonoid species belonging to the Tetragonitoidea (Anagaudryceras limatum) and Desmoceratoidea (Pachydiscus kamishakensis and Damesites aff. sugata), based on excellent material preserved in situ within the body chamber, and retaining an aragonitic shell wall. The lower jaws of the three species are assigned to an intermediate form between anaptychus and aptychus types for the first two species and the rhynchaptychus type for the third species. Their black, presumably originally chitinous outer lamella is wholly covered with a calcareous layer. The calcareous layer is composed of aragonite in D. aff. sugata and A. limatum, and calcite in P. kamishakensis. The microstructure of the outer calcareous layer differs among the three species, i.e. granular in A. limatum, spherulitic prismatic in D. sugata, and prismatic in P. kamishakensis, all of which can be distinguished from the lamellar and spongy structure of the outer‐paired calcitic plates of the typical aptychus‐type lower jaws in some Jurassic and Cretaceous Ammonitina and Ancyloceratina. Our study suggests that most Jurassic and Cretaceous ammonoids possessed an outer calcareous layer in their lower jaws, although its mineralogy, microstructure and relative thickness vary among different taxa. □Ammonoidea, Cretaceous, Desmoceratoidea, lower jaw, microstructure, Tetragonitoidea.     

Purification and amino acid composition of the hyperglycemic neurohormone from the sinus gland ofOrconectes limosus and comparison with the hormone fromCarcinus maenas

Summary The hyperglycemic neuropeptide was purified to homogeneity from sinus glands of the crayfish,Orconectes limosus, by a simple two-step procedure consisting of preparative polyacrylamide gel electrophoresis followed by gel chromatography on Sephadex G-50. A total of 40 g was obtained from 1,670 lyophilized sinus glands. The molecule consists of 58 amino acid residues plus an undetermined number of Trp residues. The following amino acid composition was found: Asx₈; Thr₂; Ser₃; Glx₆; Pro₁; Gly₂; Ala₃; 1/2 Cys₄; Val₅; Met₁; Ile₃; Leu₅; Tyr₅; Phe₃; Trp_n.d.; His₀; Lys₃; Arg₄. A minimal MW of 6,812 was calculated. The N-terminal residue appears to be blocked. Analysis of the pure hormone on an isoelectric focusing gel gave an pI of 5.04–5.10. The hormone differs from that ofCarcinus (Keller and Wunderer, 1978) in its amino acid composition and pI (Carcinus: 4.55–4.63). The following features are common for both theOrconectes and theCarcinus hormone: the size of the molecule, the blocked N-terminus, the presence of two intrachain disulfide bridges and the general acidic nature. A dose ofOrconectes hormone which is highly effective in this species has no or only very little effect inUca, whereas the same dose ofCarcinus hormone, which is markedly hyperglycemic in the brachyuranUca, exhibits no effect in the astacuranOrconectes. In animals of 10 g live weight, injection of 1.9 pmol/animal causes a threefold increase in the hemolymph glucose level.Dedicated to Professor L.H. Kleinholz on the occasion of his 70^th birthday     

Biochemical phylogeny of seven Indian species of the montium subgroup of Drosophila

Seven species of the montium subgroup of Drosophila found in South India were analysed with polyacrylamide disc electrophoresis. Eleven loci coding for enzymes were surveyed. The genetic distances between species have been measured. The dendrogram revealed three clusters. The first cluster includes D. nagarholensis, D. agumbensis, D. jambulina and D. kikkawai; the second group consists of D. truncata and D. anomelani; while D. mysorensis was the only species of the third group.We dedicate this paper to our Professor N. B. Krishnamurthy on the eve of his 60^th birthday.     

Chloroplast genome aberration in micropropagation-derived albino <Emphasis Type="Italic">Bambusa edulis</Emphasis> mutants, <Emphasis Type="Italic">ab1</Emphasis> and <Emphasis Type="Italic">ab2</Emphasis>

Two albino mutants (ab1 and ab2) have been derived from long-term shoot proliferation of Bambusa edulis. Based on transmission electronic microscopy data, the chloroplasts of these mutants were abnormal. To study the mutation of gene regulation in the aberrant chloroplasts, we designed 19 pairs of chloroplast-encoded gene primers for genomic and RT-PCR. Only putative NAD(P)H-quinone oxidoreductase chain 4L (ndhE; DQ908943) and ribosomal protein S7 (rps7; DQ908931) were conserved in both the mutant and wild-type plants. The deletions in the chloroplast genome of these two mutants were different: nine genes were deleted in the chloroplast genomic aberration in ab1 and 11 genes in ab2. The chloroplast genes, NAD(P)H-quinone oxidoreductase chain 4 (ndhD; DQ908944), chloroplast 50S ribosomal protein L14 (rpl14; DQ908934), and ATP synthase beta chain (atpB; DQ908948) were abnormal in both mutants. The gene expressions of 18 of these 20 genes were correlated with their DNA copy number. The two exceptions were: ATP synthase CF0 A chain (atpI; DQ908946), whose expression in both mutants was not reduced even though the copy number was reduced; ribosomal protein S19 (rps19; DQ908949), whose expression was reduced or it was not expressed at all even though there was no difference in genomic copy number between the wild-type and mutant plants. The genomic PCR results showed that chloroplast genome aberrations do occur in multiple shoot proliferation, and this phenomenon may be involved in the generation of albino mutants.     

Tooth replacement patterns in young Caiman sclerops

Although there are many reports of tooth replacement patterns in lower vertebrates, few show the range of pattern to be found in a number of similar aged specimens of one species. Fifteen specimens of Caiman sclerops, head length 4–5 cms, were examined by a radiographic technique and their tooth replacement patterns analysed. Whole head radiography and dissected head radiographs were compared and the resulting tooth replacement waves were found to be comparable. Wave replacement (sensu Edmund, '60) in odd and even tooth positions in the tooth row was observed in all the specimens examined. Whereas most waves passed in a cephalad direction, wave reversal (caudad) was also observed, particularly in the anterior parts of the jaws. In some specimens simple alternation in tooth replacement was observed, particularly in the mid-portion of each quadrant. The smooth, age-related change-over from cephalad to caudad demonstrated by Edmund ('62) in captive Alligator mississippiensis was not observed in wild specimens of Caiman sclerops.     

Plant distribution in relation to soil properties of reclaimed lands on the West Coast of Korea

Plant species distribution was studied on five reclaimed lands and one intertidal flat (control) on the western coast of Korea. Nineteen soil properties were analyzed. Of these, soil moisture, electrical conductivity, and levels of Na and Cl had the greatest effect on plant distribution. The plant species were divided into four groups, according to the amount of soil moisture found at their habitats.Triglochin maritimum andTypha angustata were found on the wettest sites;Phragmites communis, Carex scabrifolia, Suaeda japonica, Zoysia sinica, andSalicornia herbacea in places with relatively high moisture;Aster tripolium andPhacelurus latifolius in areas with medium levels of moisture; andAtriplex subcordata, Chenopodium virgatum, andTrifolium repens in the driest areas. The species also were divided into four groups, according to the degree of soil electrical conductivity: Highest,S. herbacea, Limonium tetragonum, Suaeda asparagoides, andS. japonica; Relatively high,A. tripolium, C. scabrifolia, P. communis, Artemisia scoparia, andZ sinka; Relatively low,Setaria viridis, C. virgatum, Sonchus brachyotus, A. subcordata, Calamagrostis epigeios, andT. angustata; and Lowest,Imperata cylindrica var.koenigii, Aeschynomene indica, Lotus corniculatus var.japonicus, andT. repens. On reclaimed land, plant species were found in zones, according to the degree of desalinization (i.e., levels of Na and Cl).     

The epiphytic communities of various ecological types of aquatic vegetation of five pastoral ponds

Five small water bodies located within the agricultural region of Wielkopolska (west Poland) underwent investigation. Periphyton samples were collected from various macrophyte habitats representing rush vegetation (in five water bodies), submerged aquatic plants (in three) and nymphaeids (in one): Palędzie — Ceratophyllum demersum, Potamogeton crispus, Typha latifolia; Batorowo — Phragmites australis; Piotrowo — Potamogeton natans, Ceratophyllum submersum, Typha latifolia; Tarnowo Podgórne — Typha latifolia; Dąbrówka — Zannichellia palustris, Potamogeton pectinatus, Phragmites australis. The main goal of the study was to determine the composition and abundance of the periphytic communities inhabiting various types of rush and water vegetation of five water bodies located within a mid-field landscape area. Diatoms such as Achnanthidium minutissimum, Amphora ovalis, Cocconeis placentula orNavicula cincta revealed significantly higher densities in the zone of elodeids, while green algae prevailed among nymphaeids. As a result of this study it was found that the epiphytic algae were characterised by much lower diversity in respect to a specific water body, though much greater diversity was observed in its relation to the type of substratum. Two types of habitats were distinguished — the first of simple build (helophytes and nympheids) and the second containing the complicated architecture of plant stems (elodeids).     

Vegetation of alpine marshland and its neighboring areas,northern part of Sichuan Province,China

To obtain the characteristics of Chinese alpine grassy marshland, the vegetation of Ruoergai marshland, which is the largest peatland in China, and of neighboring areas was surveyed along mountain slopes in three areas, Ouhailao, Waqie and Kaharqiao. Based on the clustering of 122 1 m × 1 m quadrats surveyed, the vegetation was grouped into 8 types. From bottom to top of mountain slopes, the dominant species, zonally established, were: 1) Carex enervis and Equisetum limosum; 2) Carex meyeriana; 3) Deschampsia caespitosa, Caltha scaposa and Anemone obtusiloba; 4) Koeleria cristata; 5) Kobresia tibetica and Caltha scaposa; 6) Blysmus sinocompressus; 7) Polygonum sphaerostachyum and Trollius ranuncloides; and 8) Ranunculus pedicularis. In this order, species richness increased gradually along the slopes. A principal component analysis demonstrated that water depth partly regulated the establishment of vegetation. The geographical difference of vegetation was also observed, in particular, in Waqie. Likewise, grazing is considered to modify this vegetation.