The morphology and evolution of the ventral gill arch skeleton in batoid fishes (Chondrichthyes: Batoidea)

The ventral gill arch skeleton was examined in some representatives of batoid fishes. The homology of the components was elucidated by comparing similarities and differences among the components of the ventral gill arches in chondrichthyans, and attempts were made to justify the homology by giving causal mechanisms of chondrogenesis associated with the ventral gill arch skeleton. The ceratohyal is present in some batoid fishes, and its functional replacement, the pseudohyal, seems incomplete in most groups of batoid fishes, except in stingrays. The medial fusion of the pseudohyal with successive ceratobranchials occurs to varying degrees among stingray groups. The ankylosis between the last two ceratobranchials occurs uniquely in stingrays, and it serves as part of the insertion of the last pair of coracobranchialis muscles. The basihyal is possibly independently lost in electric rays, the stingray genus Urotrygon (except U. daviesi) and pelagic myiiobatoid stingrays. The first hypobranchial is oriented anteriorly or anteromedially, and it varies in shape and size among batoid fishes. It is represented by rami projecting posterolaterally from the basihyal in sawfishes, guitarfishes and skates. It consists of a small piece of cartilage which extends anteromedially from the medial end of the first ccratobranchial in electric rays. It is a large cartilaginous plate in most of stingrays. It is absent in pelagic myliobatoid stingrays. The remaining hypobranchial cartilages also vary in shape and size among batoid fishes. Torpedo and possibly the Jurassic Belemnobalis and Spathobatis possess the generalized or typical chondrichthyan ventral gill arch structure in which the hypobranchials form a Σ-shaped pattern. In the electric ray Hypnos and narkinidid and narcinidid electric rays, the hypobranchial components are oriented longitudinally along the mid-portion of the ventral gill arches. They form a single cartilaginous plate in the narkinidid electric rays, Narcine and Diplobatis. In guitarfishes and skates, the second hypobranchial is unspecialized, and in skates, it does not have a direct contact with the second ceratobranchial. In both groups, the third and fourth hypobranchials are composed of a small cartilage which forms a passage for the afferent branches of the ventral aorta and serve as part of the insertion of the coracobranchialis muscle. In sawfishes and stingrays, the hypobranchials appear to be included in the medial plate. In sawfishes, the second and third components separately chondrify in adults, but the fourth component appears to be fused with the middle medial plate. In stingrays, a large medial plate appears to include the second through to the last hypobranchial and most of the basibranchial copulae. The medial plate probably develops independently in sawfishes and stingrays. Because the last basibranchial copula appears to be a composite of one to two hypobranchials and at least two basibranchial copulae, the medial plate may be formed by several developmental processes of chondrogenesis. More detailed comparative anatomical and developmental studies are needed to unveil morphogenesis and patternings of the ventral gill arch skeleton in batoid fishes.     

Sensillary morphology on the rostral apex and their possible role in prey location behaviour of the carnivorous stinkbug,Eocanthecona furcellata (Wolff) (Heteroptera: Pentatomidae)

Eocanthecona furcellata (Wolff), the carnivorous heteropteran, demonstrates interesting feeding mechanisms that suggest the involvement of the antennal and labial tip sensilla. This study was conducted to identify the morphology of various sensilla present on the labial tip of this insect using scanning electron microscopy. Four morphologically different types of trichoid sensilla comprise the largest and most numerous sensilla and occur throughout the surface of the labial tip. Three new and unique types of sensilla were discovered. Long hairs with profusely branched shafts are present at the entrance of the rostral groove. An oval‐shaped peg surrounded by sensory hairs with branched shafts and a short, stout peg encircled by a group of long hair‐like sensilla was found among the sensilla population of two lobes. The morphology of the new sensilla is given and possible functions of individual receptors are suggested on morphological grounds.     

Comparative anatomy of the cheek muscles of Korean cobitid fishes (Ostariophysi: Cypriniformes), with the comments on their phylogenetic relationships

Cheek muscles of 16 species of all Korean cobitid species belong to six genera were examined and described in detail, with comments on their phylogenetic relationships made on the basis of characteristics of cheek muscles. Korean cobitids were divided into two groups, the Cobitis and Misgurnus groups, by five characters related to three cheek muscles (adductor mandibulae, preorbitalis, and retractor arcus palatine). The former group, comprising Cobitis, Iksookimia, Kichulchoia, Koreocobitis, and Niwaella, is defined by four apomorphies, and the latter, including Misgurnus, by a single apomorphy.     

Development of the nidicolous tadpoles of Eupsophus emiliopugini (Anura: Cycloramphidae) until metamorphosis,with comments on systematic relationships of the species and its endotrophic developmental mode

Vera Candioti, M.F., Nuñez, J.J. and Úbeda, C. 2011. Development of the nidicolous tadpoles of Eupsophus emiliopugini (Anura: Cycloramphidae) until metamorphosis, with comments on systematic relationships of the species and its endotrophic developmental mode. —Acta Zoologica (Stockholm) 92 : 27–45. Species of Eupsophus are unique within Alsodinae in having nidicolous tadpoles. They are characterized by traits typical of generalized exotrophic (e.g., oral disc and spiracular tube) and endotrophic larvae (e.g., scant pigmentation and large hind limbs). The larval morphology and development of E. emiliopugini, including external, buccal, and musculoskeletal features, is described herein. Like the larvae of other alsodines, these larvae have four lingual and four infralabial papillae, quadratoethmoid process, and an m. rectus cervicis with a double insertion. Among the traits exclusive to the genus are: the absence of the pseudopterygoid process and quadrato‐orbital commissure; presence of the m. subarcualis rectus I with two slips; and presence of the m. subarcualis rectus II–IV inserting on Ceratobranchial II. The development and metamorphosis of Eupsophus include some characters that develop later (e.g., degeneration of mouthparts and chondrocranium with minimum calcification), characters that develop earlier (e.g., hind‐limb appearance and jaw and suspensorium ossification), and characters that develop at the same time (e.g., most external features and cranial muscles) than in most exotrophic species. Some distinctive characters (third lower labial ridge absent, general configuration of the hyobranchial skeleton, skeletal development with retention of larval traits) resemble those of other endotrophic species, and the precocious ossification of jaws and suspensorium is shared with several direct‐developing species among recent amphibians.     

Cranial morphology of Ateleopus japonicus (Ateleopodidae: Ateleopodiformes), with a discussion on metamorphic mouth migration and lampridiform affinities

The cranial osteology and myology in the ateleopodiform Ateleopus japonicus were studied. Many free bony ossicles constitute the cephalic lateral line canals and are separated from the neurocranial roof by thick gelatinous tissue. The preoperculomandibular canal is unique in having a direct connection with the infraorbital canal owing to strong reduction in the size of the preoperculum. The neurocranium is largely cartilaginous, with 6 chondrocranial and 1 dermal element being absent (or not undergoing ossification). The left and right frontals are separated by a deep groove into which a long, mobile rostral cartilage is deeply inserted. Five pairs of cartilages, including 2 pairs of menisci, are associated with the ethmoid region, allowing premaxillary protrusion without involving maxillary rotation. The levator operculi is well developed and likely generates the primary force for depressing the lower jaw. The large interhyal is tightly attached to the entire ventral margin of the operculum, and the two elements appear to function as a single unit in mouth opening. The oral cavity is large because of the posterior position of the branchial arches [the last (5th) arch is situated below the 3rd vertebra]. In pelagic individuals the head is flat with a terminal mouth and straight parasphenoid shaft, whereas in small, benthopelagic individuals the head is rounded with an inferior mouth and bent parasphenoid shaft. “Bending” of the parasphenoid with a dorsally elevated apex is considered the result of the posterior migration of the mouth during the habitat shift. Ateleopodiform characters are discussed phylogenetically and the deep insertion of the rostral cartilage into an open space in the ethmoid region is suggested as a synapomorphy of the order and Lampridiformes.     

Seven new species within western Atlantic Starksia atlantica, S. lepicoelia, and S. sluiteri (Teleostei, Labrisomidae), with comments on congruence of DNA barcodes and species

Specimens of Starksia were collected throughout the western Atlantic, and a 650-bp portion of the mitochondrial gene cytochrome oxidase-c subunit I (COl) was sequenced as part of a re-analysis of species diversity of western Central Atlantic shorefishes. A neighbor-joining tree constructed from the sequence data suggests the existence of several cryptic species. Voucher specimens from each genetically distinct lineage and color photographs of vouchers taken prior to dissection and preservation were examined for diagnostic morphological characters. The results suggest that Starksia atlantica, Starksia lepicoelia, and Starksia sluiteri are species complexes, and each comprises three or more species. Seven new species are described. DNA data usually support morphological features, but some incongruence between genetic and morphological data exists. Genetic lineages are only recognized as species if supported by morphology. Genetic lineages within western Atlantic Starksia generally correspond to geography, such that members of each species complex have a very restricted geographical distribution. Increasing geographical coverage of sampling locations will almost certainly increase the number of Starksia species and species complexes recognized in the western Atlantic. Combining molecular and morphological investigations is bringing clarity to the taxonomy of many genera of morphologically similar fishes and increasing the number of currently recognized species. Future phylogenetic studies should help resolve species relationships and shed light on patterns of speciation in western Atlantic Starksia.     

Laboratory studies on the biology and host range of Dichrorampha odorata (Lepidoptera: Tortricidae), a biological control agent for Chromolaena odorata (Asteraceae)

Dichrorampha odorata (Lepidoptera: Tortricidae) is a moth from Jamaica whose larvae bore into, and kill, the shoot tips of the invasive alien plant, Chromolaena odorata (L.) King and Robinson (Asteraceae). This study reports aspects of the biology of D. odorata, and also determined the host specificity (larval and adult no-choice trials) of the moth. Adults were short lived (ranging from 2 to 7 days), with females laying a mean of 15.4 eggs. Eggs took 9 days to hatch, larvae 20–23 days to develop and the pupal stage lasted 11–12 days, giving an overall lifecycle period of 41–45 days. Larval no-choice tests using 34 asteraceous test species indicated that only C. odorata could sustain complete development of D. odorata to adulthood, although there was slight initial boring 14 test species (plus chromolaena). Results from the adult nochoice trials, in which seven test-plant species were exposed to D. odorata, were consistent with those from larval trials, with larval damage, pupae and adults of D. odorata recorded from only C. odorata. This confirmed that only C. odorata is a suitable host for D. odorata in South Africa. Permission has subsequently been granted for the release of D. odorata in South Africa, thus making it the first shoot-tip attacking agent to be released against C. odorata. It is hoped that in the field, high levels of damage by the moth will reduce the height and therefore competitiveness of C. odorata, thereby contributing to the success of biological control of this plant.     

Seasonal and regional occurrence of <Emphasis Type="Italic">Acanthocephalus</Emphasis> sp. (Acanthocephala: Echinorhynchidae) in fishes and isopods (<Emphasis Type="Italic">Asellus hilgendorfi</Emphasis>) in a lake system in northern Japan

 The echinorhynchid acanthocephalan Acanthocephalus sp. was collected and described from four species of fishes (rainbow trout Oncorhynchus mykiss, Sakhalin huchen Hucho perryi, Japanese pond smelt Hypomesus nipponensis, and threespine stickleback Gasterosteus aculeatus) from a lake system, the Tsugaru-Jūniko Lakes, in Aomori Prefecture, northern Japan. In rainbow trout, the prevalence and intensity of infection markedly differed between lakes, and the fish were most frequently and most heavily infected in the lakes with a dense population of the isopod intermediate host Asellus hilgendorfi. In isopods, the prevalence of acanthocephalan larvae increased in the late winter and reached its highest level in March or April. In rainbow trout, male worms were abundant from winter to spring, and female worms were immature during these seasons. Gravid females were abundant in summer and autumn. These findings indicate that Acanthocephalus sp. is an annual species and its recruitment from the intermediate host to the fish occurs mainly in winter and spring. Received: January 9, 2002 / Accepted: April 18, 2002 Acknowledgments We thank Professor Shōichi Saito, Faculty of Education, Hirosaki University, for his encouragement during this study. Thanks are also due to many students of the Nature Study Laboratory, Faculty of Education, Hirosaki University, for their assistance in the field. We are greatly indebted to the Iwasaki Village Office and Fukaura Forestry Office for giving us permission for the survey. Correspondence to:A. Ohtaka     

Development and Degeneration of Flight Muscles in Neochetina eichhorniae (Coleoptera; Curculionidae), Potential Biocontrol Agent of the Aquatic Weed, Eichorniae crassipes

The water hyacinth weevil, Neochetina eichhorniae, is an effective biological control agent of the aquatic weed Eichorniae crassipes. The adults under field conditions have degenerated indirect flight muscles that explains their inability to fly. A study on the factors initiating flight muscle development in adults was carried out. Among the various abiotic factors studied, density of weevils per plant and high temperature in presence of food initiated and accelerated flight muscle development. Absence of food did not influence muscle development. No inter-relationship between flight muscle development and degeneration could be observed.     

不同茶园生态环境对茶树生育及茶叶品质的影响

茶树是一种喜荫好湿的多年生作物,它的整个生长发育过程及其高产稳产的获得,与茶园生态环境密切相关。而茶叶品质的形成和优劣则更受生态环境制约。为探讨不同茶园生态环境对茶树生育及茶叶品质的影响,特于1984—1986年在“凫绿”产地开展研究。     

Field Evaluation of Amitus bennetti (Hymenoptera: Platygasteridae), a Parasitoid of Bemisia argentifolii (Hemiptera: Aleyrodidae), in Cotton and Bean

Field cage experiments were conducted in Riverside, California to quantify the impact of releases of the parasitoid Amitus bennetti Viggiani & Evans on mortality of the whitefly Bemisia argentifolii Bellows & Perring. Single-row 50-m-long plots were planted with either cotton or bean. Cages were erected over the plants in each row, and adult whiteflies were released into the cages. Approximately 10 days later, adult parasitoids were released. Marked individual whiteflies were scored every 4 days for 6 weeks. Paired life tables were then constructed from census data from release and control cages over a single whitefly generation. Total whitefly mortality in release cages (71% in bean, 61% in cotton) was significantly greater than in control cages (25% in bean, 34% in cotton). The marginal rate for mortality attributable directly to the parasitism was 0.535 in the bean plots and 0.201 in the cotton plots. In addition, other mortality was greater in the release plots, possibly reflecting death of parasitized hosts before larval parasitoids could complete development. Parasitism was the greatest mortality factor in the study.     

Morphological and morphometric appraisal of the spermatophore of the southern hermit crab Isocheles sawayai (Anomura: Diogenidae), with comments on gonopores in both sexes

The spermatophore morphology of the hermit crab Isocheles sawayai from southwestern Atlantic (Brazil) is described. The spermatophores show similarities with those described for other members of the family Diogenidae, especially with the recently described Loxopagurus loxochelis. The spermatophore is composed of three major regions: a sperm filled head or ampulla, a columnar stalk and a foot or pedestal. The spermatophores show specific morphology in having a circular ampulla, and a constriction or neck between the ampulla (100 μm) and the thin (27 μm), long stalk (500 μm). The stalk penetrates less than half way into the spermatophore head. Most spermatophores show one of the small posterior projections on the underside of the ampulla as being bigger than the other, making it asymmetrical. The size of the spermatophore is related to hermit crab size with direct relationships found between spermatophore ampulla width, total length, and peduncle length with shield length of the hermit crab. The morphological characteristics of the spermatophore of I. sawayai are species-specific distinguishing it from other members of the family, and are useful to infer further phylogenetic relationships.     

Development of chiral drugs in Japan: An update on regulatory and industrial opinion

The purpose of this commentary is to provide information on the present status of the racemate/enantiomer debate in Japan and current industrial and regulatory attitudes to chiral drugs in Japan. It provides an update of our previous paper (Shindo and Caldwell, Chirality 3:91–93, 1991), and the interested reader is referred to this for background information. © 1995 Wiley-Liss, Inc.     

Radiation, multiple dispersal and parallelism in the skinks, Chalcides and Sphenops (Squamata: Scincidae), with comments on Scincus and Scincopus and the age of the Sahara Desert

Phylogenetic analysis using up to 1325 base pairs of mitochondrial DNA from 179 specimens and 30 species of Chalcides, Sphenops, Eumeces, Scincopus and Scincus indicates that Sphenops arose twice independently within Chalcides. It is consequently synonymized with that genus. Chalcides in this broader sense originated in Morocco, diversifying into four main clades about 10 Ma, after which some of its lineages dispersed widely to cover an area 40 times as large. Two separate lineages invaded the Canary Islands and at least five main lineages colonized southern Europe. At least five more spread across northern Africa, one extending into southwest Asia. Elongate bodies with reduced limbs have evolved at least four times in Chalcides, mesic 'grass-swimmers' being produced in one case and extensive adaptation to life in loose desert sand in two others. In clade, Chalcides striatus colonized SW Europe from NW Africa 2.6 Ma and C. chalcides mainland Italy 1.4 Ma, both invasions being across water, while C. c. vittatus reached Sardinia more recently, perhaps anthropogenically, and C. guentheri spread 1200km further east to Israel. C. minutus is a composite, with individuals from the type locality forming a long independent lineage and the remaining ones investigated being most closely related to C. mertensi. In the Northern clade, C. boulengeri and C. sepsoides spread east through sandy habitats north of the Sahara about 5 Ma, the latter reaching Egypt. C. bedriagai invaded Spain around the same time, perhaps during the Messinian period when the Mediterranean was dry, and shows considerable diversification. Although it is currently recognized as one species, the C. ocellatus clade exhibits as much phylogenetic depth as the other main clades of Chalcides, having at least six main lineages. These have independently invaded Malta and Sardinia from Tunisia and also southwest Arabia C. o. humilis appears to have spread over 4000 km through the Sahel, south of the Sahara quite recently, perhaps in the Pleistocene. In the Western clade of Chalcides, C. delislei appears to have dispersed in a similar way. There were also two invasions of the Canary Islands: one around 5 Ma by C. simonyi, and the other about 7 Ma by the ancestor of C. viridanus+C. sexlineatus. C. montanus was believed to be related to C. lanzai of the Northern clade, but in the mtDNA tree it is placed within C. polylepis of the Western clade, although this may possibly be an artifact of introgression. The Eumeces schneideri group, Scincopus and Scincus form a clade separate from Chalcides. Within this clade, the geographically disjunct E. schneideri group is paraphyletic. One of its members, E. algeriensis is the sister taxon to Scincopus, and Scincus may also be related to these taxa. The phylogeny suggests Scincopus entered desert conditions in Africa, up to 9.6 Ma and the same may have been true of Scincus up to 11.7 Ma. Scincus appears to have diversified and spread into Arabia around 6 Ma. Dates of origin and divergence of these skinks, desert Chalcides and other squamates agree with recent geological evidence that the Sahara is at least 5-7 My old. The subspecies Chalcides viridanus coeruleopunctatus is upgraded to the species level as C. coeruleopunctatus stat nov., on the basis of its large genetic divergence from C. v. viridanus.     

Phylogenetic relationships,subdivision, and biogeography of the cyprinid tribe Labeonini (sensu ) (Teleostei: Cypriniformes), with comments on the implications of lips and associated structures in the labeonin classification

The Labeonini (sensu Rainboth, 1991) is a tribe of the subfamily Cyprininae, the largest subfamily of Cypriniformes. With around 400 species in 34 genera, this tribe is widely distributed in the freshwaters of tropical Africa and Asia. Most species are adapted to fast-flowing streams and rivers, and exhibit unique morphological modifications associated with their lips and other structures around the mouth. The monophyly of this tribe has been tested and generally accepted in previous morphological and molecular studies. The major objectives of this study were to reconstruct the phylogenetic relationships within the tribe Labeonini, test its monophyly and explore the taxonomic subdivisions, intrarelationships and biogeography of the group. The value of the morphological characters associated with the lips and other associated structures in the taxonomic classification of labeonins was also discussed. Nucleotide sequences (3867 bp) of four unlinked nuclear loci were obtained from 51 species in 18 Labeonini genera from throughout the range of the tribe. Maximum parsimony, partitioned maximum likelihood and partitioned Bayesian analyses were used for phylogenetic inference from combined and separate gene data sets. Based on our results, the monophyly of Labeonini was well supported. Two major clades could be recovered within the tribe. Three subclades could further be recognized from the first clade. These clades/subclades are not consistent with groupings of any of previous workers using either morphological or molecular characters for phylogenetic inference. Only five currently recognized genera in this analysis are monophyletic. The similarity between some lips and associated structures (e.g. suctorial discs) of labeonins may due to convergence or parallelism instead of common ancestry. Labeonins of Southeast Asia, India and China are closely related to each other; the multiple clades of African taxa do not form a single monophyletic group, indicating multiple, independent dispersal events of labeonins into Africa from Asia.     

Laboratory experiments on factors affecting oviposition site selection in Toxorhynchites amboinensis (Diptera: Culicidae), with a report on the occurrence of egg cannibalism

Laboratory experiments tested the effects of water quality and the presence of conspecific and heterospecific immatures on oviposition by Toxorhynchites amboinensis (Doleschall). The females showed a highly significant preference for oak leaf infusion water over distilled water. When twenty starved third and fourth instar Tx.amboinensis larvae were present in the water, substantially fewer eggs were counted from pots containing these conspecifics, than from controls in which no larvae were present. Numbers of eggs from pots containing starved second instar larvae did not differ significantly from controls. Observations of larval behaviour while oviposition was occurring suggested that egg numbers were reduced in containers because of egg cannibalism with third and fourth instar larvae, and not because the larvae caused a deterrent effect. Subsequent experiments confirming the occurrence of substantial egg cannibalism by third and especially fourth instar larvae are described. As with larvae, the presence of Tx.amboinensis pupae in the water had little effect on oviposition. If placed in the water 24 h prior to test, pupae very slightly enhanced its attractiveness, but if introduced immediately before test there appeared to be a slight deterrent effect. With heterospecific larvae, twenty fourth instar Ae.aegypti larvae introduced into infusion water 24 h before test rendered the water slightly attractive, while water in which Ae.aegypti larvae had been reared for 48 h proved highly repellent.