Anterior Pair Research Articles

A NEW CRYPTIC SPECIES OF GECKO OF THE GENUS Hemidactylus Oken, 1817 (REPTILIA: GEKKONIDAE) FROM SOUTHERN INDIA

A new species of gecko superficially resembling Hemidactylus maculatus is described from the southern Indian state of Tamil Nadu. Hemidactylus acanthopholis sp. nov. is a large sized Hemidactylus, SVL at least 91.7mm. Dorsal scalation on trunk granular, intermixed with enlarged, fairly regularly arranged longitudinal rows of 18–20 trihedral, moderately keeled, striated tubercles of equal size on dorso-lateral aspect, 2–3 rows of tubercles on mid-dorsal smaller in size, approximately two dorsal granular scales wide. Two large rounded and one small internasal between nasals. Two pairs of postmentals, anterior pair is twice as long and wide as the posterior pair. Scales on ventral trunk arranged in 35–40 rows. Lamellae divided, 9, 11, 10, 10, 10 on manus, and 10, 12, 12, 12, 12 on pes respectively on digits I–V. Caudal pholidosis on dorsal aspect, consist of small, striated scales intermixed with large rounded un-keeled tubercles, scales sub-equal throughout and a series of large eight enlarged, moderately keeled and weakly striated and flattened tubercles in a whorl on each caudal segment. Femoral pores, 19–21 on each side separated medially by 13–14 pore-less scales.

A new sibling species of Notobryon (Gastropoda, Nudibranchia) from the Caribbean Sea

A new Scyllaeidae of the genus Notobryon is described from Guadeloupe, in the Lesser Antilles. Notobryon caribbaeus sp. nov. is characterized by having the anterior pair of body lobes remarkably bigger than the posterior pair, a stomach with eight triangular plates, a black and very wide ampulla, a lemon-shaped bursa copulatrix and a complex and well-differentiated sponge-like prostate. The first Caribbean records of Notobryon were provisionally assigned to the Australian species Notobryon cf. wardi and later transferred to Notobryon panamica. However, the structure of the male genital system is one of the main morphological characters to discriminate species in the genus and the presence of a prostate in N. caribbaeus sp. nov. distinguishes it from N. panamica, which remains confined to the eastern Pacific. Of the remaining four species in the world, only Notobryon bijecurum shares this character, but its external anatomy is different: it lacks a bursa copulatrix and the deferent duct is much shorter. Notobryon caribbaeus sp. nov. was captured in the context of an intensive expedition (‘Karubenthos’) organized by the Muséum National d'Histoire Naturelle, Paris and its description raises the total inventory of sea slugs in Guadeloupe to 150.

Levisunguis subaequalis n. g., n. sp., a tongue worm (Pentastomida: Porocephalida: Sebekidae) infecting softshell turtles, Apalone spp. (Testudines: Trionychidae) in the southeastern United States

A new tongue worm (Pentastomida) belonging to the Sebekidae Sambon, 1922 (Porocephaloidea Sambon, 1922) is described based on exemplars collected from softshell terrapins Apalone spinifera aspera (Agassiz) and Apalone ferox (Schneider) in the southeastern United States; a new genus is erected to accommodate the new species. The new species belongs in the Sebekidae because adults possess four simple hooks arranged in a trapezoid pattern on the ventral surface of the cephalothorax, a mouth opening between the anterior and posterior pairs of hooks, a terminal anus, an elongated uterus with preanal uterine pore, and a Y-shaped seminal vesicle. Nymphs possess geminate hooks, and the new species has an aquatic life-cycle in which nymphs become encapsulated in the body cavity of a freshwater fish and mature in the lungs of a terrapin. The new genus is distinct from other genera in the Sebekidae primarily by differences in hook morphology and the fact that representatives use a terrapin as a definitive host. Nymphs infecting fish and presumed to be the new species matured as postlarval juveniles conspecific with the new species when they were fed to the eastern mud turtle, Kinosternon subrubrum (Lacépède). Nymphs of the new species are anatomically similar to but larger than nymphs of Sebekia mississippiensis Overstreet, Self & Vliet, 1985 found in the mesentery of fishes captured in Florida, U.S.A. Adults of the new species differ from those of S. mississippiensis based on hook features, chloride cell pore pattern on annuli, body size, and use of a turtle rather than crocodilian definitive host. The new species is the third North American member of the Sebekidae.

Serotonin-immunoreactive neurons in the ventral nerve cord of Remipedia (Crustacea): support for a sister group relationship of Remipedia and Hexapoda?

BackgroundRemipedia were initially seen as a primitive taxon within Pancrustacea based on characters considered ancestral, such as the homonomously segmented trunk. Meanwhile, several morphological and molecular studies proposed a more derived position of Remipedia within Pancrustacea, including a sister group relationship to Hexapoda. Because of these conflicting hypotheses, fresh data are crucial to contribute new insights into euarthropod phylogeny. The architecture of individually identifiable serotonin-immunoreactive neurons has successfully been used for phylogenetic considerations in Euarthropoda. Here, we identified neurons in three species of Remipedia with an antiserum against serotonin and compared our findings to reconstructed ground patterns in other euarthropod taxa. Additionally, we traced neurite connectivity and neuropil outlines using antisera against acetylated α-tubulin and synapsin.ResultsThe ventral nerve cord of Remipedia displays a typical rope-ladder-like arrangement of separate metameric ganglia linked by paired longitudinally projecting connectives. The peripheral projections comprise an intersegmental nerve, consisting of two branches that fuse shortly after exiting the connectives, and the segmental anterior and posterior nerve. The distribution and morphology of serotonin-immunoreactive interneurons in the trunk segments is highly conserved within the remipede species we analyzed, which allows for the reconstruction of a ground pattern: two posterior and one anterior pair of serotonin-immunoreactive neurons that possess a single contralateral projection. Additionally, three pairs of immunoreactive neurons are found in the medial part of each hemiganglion. In one species (Cryptocorynetes haptodiscus), the anterior pair of immunoreactive neurons is missing.ConclusionsThe anatomy of the remipede ventral nerve cord with its separate metameric ganglia mirrors the external morphology of the animal’s trunk. The rope-ladder-like structure and principal architecture of the segmental ganglia in Remipedia corresponds closely to that of other Euarthropoda. A comparison of the serotonin-immunoreactive cell arrangement of Remipedia to reconstructed ground patterns of major euarthropod taxa supports a homology of the anterior and posterior neurons in Pancrustacea. These neurons in Remipedia possess unbranched projections across the midline, pointing towards similarities to the hexapod pattern. Our findings are in line with a growing number of phylogenetic investigations proposing Remipedia to be a rather derived crustacean lineage that perhaps has close affinities to Hexapoda.

Four new species of Colobomatus (Copepoda: Philichthyidae) parasitic in the lateral line system of marine finfishes captured off the Ryukyu Islands, Japan, with redescriptions of Colobomatus collettei Cressey, 1977 and Colobomatus pupa Izawa, 1974

This study describes four new species of Colobomatus Hesse, 1873 and redescribes Colobomatus collettei Cressey, 1977 and Colobomatus pupa Izawa, 1974 based on females collected from the sensory canals of seven finfish species from off the Ryukyu Islands, southern Japan. Colobomatus pteroisi sp. nov. from Pterois volitans is unique in having a mid-lateral pair of cephalic processes; Colobomatus acanthuri sp. nov. from Acanthurus olivaceus possesses a short neck between the head and first pair of thoracic processes and tiny spinules and three claws apically on the cephalic, thoracic and genital processes; Colobomatus gymnocranii sp. nov. from Gymnocranius griseus has an anterior pair of papillose thoracic processes that are twice as long as the posterior pair of spinulose processes; Colobomatus absens sp. nov. from Pterocaesio digramma is unique in lacking a posterior pair of thoracic processes. New host and locality records for C. collettei and C. pupa are also reported herein.http://www.zoobank.org/urn:lsid:zoobank.org:pub:BEB140D5-8936-4B47-B8B9-738BFABF37E1

Redescription of Pseudacanthocanthopsis secunda (Yamaguti and Yamasu, 1960) (Copepoda: Chondracanthidae) parasitic on marine fishes from the Seto Inland Sea, Japan and the East China Sea off Japan and Korea

A redescription of the chondracanthid copepod Pseudacanthocanthopsis secunda (Yamaguti and Yamasu, 1960) is provided based on adult females collected from the Indian perch, Apogon lineatus Temminck and Schlegel, 1842, captured in the Seto Inland Sea, Japan, and the East China Sea off Japan and Korea, along with additional material from the fine-patterned puffer Takifugu poecilonotus (Temminck and Schlegel, 1850) and red seabream Pagrus major (Temminck and Schlegel, 1843) captured in the Seto Inland Sea. The male of P. secunda is also described for the first time. Our results revealed that P. secunda is a valid member of Pseudacanthocanthopsis, and it can be distinguished from the other three congeners by having one ventrolateral and two anterior pairs of rounded head processes, a reniform trunk, a double row of teeth along the concave margin of the mandible and a lateral swelling on the leg 1 protopod in the female. http://www.zoobank.org/urn:lsid:zoobank.org:pub:7AD5211F-66EF-464A-B9C9-E21C19ECFDC7

Rethinking the Supraclavicular Field: Anterior Wedged Pair 3D Conformal Radiation Therapy Versus Single Anterior Oblique Field as Treatment of the Axillary Apex and Supraclavicular Fossa in Node Positive Breast Cancer

Rethinking the Supraclavicular Field: Anterior Wedged Pair 3D Conformal Radiation Therapy Versus Single Anterior Oblique Field as Treatment of the Axillary Apex and Supraclavicular Fossa in Node Positive Breast Cancer

A new genus of gall-dwelling thrips from Costa Rica (Thysanoptera: Phlaeothripidae: Phlaeothripinae)

A new genus and species of thrips, Fourbethrips fiorella, inhabiting stems, petioles and leaf vein galls of a Melastomataceae from Costa Rica is described. The galls are induced by an unidentified gall midge larva (Cecidomyiidae). This new thrips can be distinguished from other genus and species of Phlaeothripinae by the shape of the pelta, the position of maxillary stylets in the head, the reduced and acute anterior pair of postocular setae, the long and capitate posterior pair of postocular setae, the presence of a group of minute setae, and a pair of short ventral setae in the middle area of the abdominal sternites II-VII. The tergites II-VII have a pair of campaniform sensillae.

Prevalence, severity, and clinical determinants of oral impacts in older people in Bosnia and Herzegovina

This study aimed to assess the prevalence and the severity of oral impacts and the relationships between oral health-related quality of life (OHRQoL) and clinical measures of oral function in a sample of older adults in Bosnia. The sample comprised 261 community-dwelling adults of ≥65 yr of age. Participants were randomly drawn from three senior day-centres for elderly people. Data were collected using clinical examination and a questionnaire. The OHRQoL was assessed through the Oral Impacts on Daily Performances (OIDP) measure, in terms of the prevalence, intensity, and extent of oral impacts. Overall, 55.2% reported at least one oral impact in the last 6 months. Difficulty eating (43.3%) and difficulty speaking (34.1%) were the most common impacts. These were also the most severely affected performances, while 'going out' and 'enjoying the contact of other people' were the least severe. A higher number of natural teeth, natural occluding pairs, and anterior and posterior occluding pairs were all significantly associated with a lower prevalence of oral impacts and correlated with the OIDP score, even after adjusting for sociodemographic factors. The prevalence of oral impacts was high and there was a strong and consistent association between OHRQoL and clinical dental indicators of function.

A New Species of Gecko of the Genus Hemidactylus (Reptilia: Gekkonidae) from Andhra Pradesh, India

A new species of Hemidactylus herein is described from a small population in Hyderabad, Andhra Pradesh, India. It is compared with all Indian congeneric species from which it differs by the following combination of characters; SVL 59.1 – 70.2 mm, 15 – 16 transverse rows of tubercles at midbody, 6 transverse rows of tubercles on the first segment of the tail, 6 – 7 lamellae on digit I of pes, 9 lamellae on digit IV of pes, 14 precloacal-femoral pores in males, 11 – 12 superlabials, 10 infralabials and three enlarged postcloacal spurs, posterior most spur approximately three times the size of each of the anterior pair which are of equal size to each other.

Camallanus Railliet et Henry, 1915 (Nematoda, Camallanidae) from Australian freshwater turtles with descriptions of two new species and molecular differentiation of known taxa

AbstractTwo new species of Camallanus are described from Australian freshwater turtles. Camallanus beveridgei sp. nov. is reported from Elseya dentata in Northern Territory. It differs from other species of the genus parasitic in turtles by several characters including the shape of the median ridge in the buccal capsule and the position of the anterior pair of caudal papillae in males. Camallanus sprenti sp. nov. is reported from Elseya latisternum (type host) and Emydura krefftii in northern Queensland. It is closely related to Camallanus tuckeri, and differs from the latter species in possessing a shorter oesophagus. We summarize data on morphology, distribution and specificity of 5 known Camallanus spp. from Australian turtles and provide a key for their identification. Sequence comparison of more than 500 base pairs at the 5′ end of the nuclear 28S rDNA gene confirms the status of C. sprenti and C. beveridgei as new species. Camallanus sprenti differs from the other 4 species of Camallanus from Australian turtles by 16–59 bases (3.1–11.5%) while C. beveridgei differed from the other 4 species by 23–60 bases (4.5–11.6%). Phylogenetic analysis demonstrates close interrelationships among C. tuckeri, C. sprenti and C. beveridgei, the three species with most similar buccal capsules.

Three new species of the family Pennellidae (Copepoda: Siphonostomatoida) from gobiid fishes (Actinopterygii: Perciformes) in coastal waters of the western Pacific Ocean

Three new species of pennellid copepods are described based on specimens taken from gobiid fishes. Creopelates nohmijimensis n. sp. was found on Priolepis boreus (Snyder) in the Seto Inland Sea, Japan. This new species is distinguishable from its sole congener, C. floridus Shiino, 1958, by the presence of four finely digitate lobes on the cephalothorax and in having four pairs of legs occurring closely together at the anterior end of the neck. Two new species of Cardiodectes, C. asper n. sp. and C. bertrandi n. sp., were collected, from Trimma grammistes (Tomiyama) off IzuOshima Island, Japan and Eviota sp. off the Loyalty Islands, New Caledonia, respectively. Cardiodectes asper n. sp. is distinguished from its 12 congeners by the absence of the abdomen, byhaving a trunk not longer than twice of its width, a cephalothorax with three pairs of lateral lobes, and a pair of neck lobes carrying leg 3 on the posterior surface of their bases. Cardiodectes bertrandi n. sp. is identifiable by the presence of two pairs of lateral cephalothoracic lobes, with smaller anterior pairs; a trunk twice as long as wide; and leg 3 located at the posterior end of the anterior neck lobe.

Morphology and ultrastructure of the nephridial system of Hypania invalida (Grube, 1860) (Annelida, Polychaeta, Ampharetidae)

The excretory organs of the freshwater polychaete Hypania invalida have been examined using scanning and transmission electron microscopy. Three pairs of macroscopically and ultrastructurally different nephridia are present in the thorax. Intersegmental septa in the thorax are absent, with the exception of a single diaphragm between second and third chaetiger. The first pair of nephridia is anterior to this septum, the second pair crosses the septum, with the nephrostomes anterior and the ducts and the nephridiopori posterior to it, and the third pair of nephridia is entirely posterior to the diaphragm. The first two pairs of nephridia have ciliated nephrostomes of moderate size and long nephridial ducts that extend the length of the thorax. In contrast, the third pair is characterized by short ducts and very prominent nephrostomes. Macroscopically, seven different sections of nephridial duct cells can be distinguished along the length of the first two pairs of nephridia, whereas, on an ultrastructural basis, only six different regions can be identified. Only two regions of different duct cells can be recognized in the third pair of nephridia. Cells of the two anterior pairs of nephridia show typical characteristics of transport epithelia and most likely function as excretory organs. In contrast, the duct cells of the third pair are not that much differentiated and might primarily be responsible for the release of sexual products, as sperm was observed passing through these ducts. Podocyte-like cells were observed to accompany nephridial ducts.

Five invaginations and shedding of the larval epidermis during development of the hoplonemertean Pantinonemertes californiensis (Nemertea: Hoplonemertea)

We describe the planuliform larval development of the high intertidal hoplonemertean Pantinonemertes californiensis using confocal microscopy. We discovered that the newly hatched planuliform larva has two pairs of epidermal invaginations that disappear later in development. The anterior pair of invaginations has an apparent counterpart in other planuliform nemertean larvae; they give rise to the cerebral organs in at least two other hoplonemertean species. Although the adult P. californiensis possesses cerebral organs, we were not able to distinguish the anterior invaginations after 3 days of development. The developmental fate and homology of the posterior pair of invaginations is uncertain. We show that the proboscis develops in newly hatched larvae as a fifth distinct invagination just ventral of the apical plate. P. californiensis possesses a transitory larval epidermis, composed of approximately 80 multiciliated cells, which is normally shed at 3–4 days of development at 12–16°C.

Lymph flux rates from various lymph sacs in the cane toad Rhinella marina: an experimental evaluation of the roles of compliance, skeletal muscles and the lungs in the movement of lymph

A new method for quantitatively determining lymph flux from various lymphatic sacs of an anuran, the cane toad, was developed. This method used the dye dilution principle of C(i)V(i)=C(f)V(f) following injection of Evans Blue into specific lymph sacs and measuring its appearance in the venous circulation. The apparent lymph volume was 57 ml kg(-1). The greatest rate of lymph return (0.5-0.8 ml kg(-1) min(-1)) and best linear fit of Evans Blue appearance in the circulation with time followed injections into the subvertebral lymph sac, which has direct connections to both the anterior and posterior pairs of lymphatic hearts. Rate of lymph flux from the pair of posterior lymph hearts was three times greater than the anterior pair. Rates of lymph flux were only influenced by injection volume in the crural lymph sacs, implicating lymph sac compliance as the source of the pressure for lymph movement from these sacs. Femoral lymph sac fluxes were decreased by 60% following ablation of the tendons of the sphincter ani cloacalis, abdominal crenators and piriformis. This supports a role for these muscles in generating the pressure for vertical lymph movement. Femoral lymph sac fluxes were also decreased by 70% by the insertion of a coil in the subvertebral lymph sac, preventing normal compression and expansion of this sac by the lungs. This supports a role for lung ventilation in generating the pressure for vertical movement of lymph. Contrary to previous hypotheses, fluxes from the brachial sac were not influenced by insertion of the coil into the subvertebral sac. A haemorrhage equivalent to 50% of the blood volume did not change lymph flux rates from the femoral lymph sacs. These data provide the first experimental evidence that actual lymph fluxes in the cane toad Rhinella marina depend on lymph sac compliance, contraction of specific skeletal muscles and lung ventilation to move lymph laterally and vertically to the dorsally located lymphatic hearts.

Four new species of Heth Cobb, 1898 (Rhigonematida: Hethidae) from Vietnamese diplopods

Abstract Four new species of Heth are described from diplopods collected in different parts of Viet Nam: Heth vietnamensis sp. n. and H. tonkinensis sp. n. in Ba Vi National Park, Ha Tay Province; H. taybaci sp. n. in Lai Chau Province and H. taynguyeni sp. n. in Chu Yang Sin National Park, Dak Lak Province. The new species are morphologically related to those described from Papua New Guinea, but are differentiated by the form of the female cuticular armature. Heth vietnamensis sp. n. is characterised by the posterior end of the lappets overhanging the anterior pair of the lateral spines, the similar size of spines in both pairs and the presence of two pairs of small papillae on the anterior lip of the cloacal aperture. Heth tonkinensis sp. n. can be differentiated from the other species by having the longest lappets, lateral spines with fused bases and the unequal-sized spicule heads. Heth taybaci sp. n. has the shortest lappets of the described Vietnamese species, has gaps between the lateral spines that are wider than the spine base and the presence of a bursa-like cuticular fold at cloacal aperture level. Heth taynguyeni sp. n. males also have a bursa-like cuticular fold but, unlike H. taybaci sp. n., this species is characterised by the bifurcate distal tips of the spicule and the undulating inner margin of the lappets.

Hyoid Skeleton, Its Related Muscles, and Morphological Novelties in the Frog Lepidobatrachus (Anura, Ceratophryidae)

Many traits of the skull of ceratophryines are related to the capture of large prey independently of aquatic or terrestrial feeding. Herein, detailed descriptions of the development of hyoid skeleton and the anatomy of muscles responsible for hyoid and tongue movements in Lepidobatrachus laevis and L. llanensis are provided and compared with those of other neobatrachians. The aquatic Lepidobatrachus has special features in its hyoid skeleton that integrates a set of derived features convergent with the conditions observed in non-neobatrachian anurans and morphological novelties (e.g., dorsal dermal hyoid ossification) that deviate from the generalized pattern found in most frogs. Further, reduction of fibers of muscles of buccal floor, reduction or loss of hyoid muscles (m. geniohyoideus rama lateralis, anterior pair of m. petrohyoideus posteriores), small tongue, and simplified tongue muscles are also morphological deviations from the pattern of terrestrial ceratophryines, and other aquatic ceratophryids (e.g., Telmatobius) that seem to be related to feeding underwater. The historical derived features shared with Chacophrys and Ceratophrys involved in megalophagy are conserved in Lepidobatrachus and morphological changes in the hyoglossal apparatus define a unique functional complex among anurans.

Laser Trap Characterization and Modeling of Phototaxis in Chlamydomonas reinhardtii

The unicellular protist Chlamydomonasreinhardtii swims toward light sources using an anterior pair of flagella for propulsion and an eye spot that serves as a directional photoreceptor. Free-swimming Chlamydomonas rotate about the long axis of the cell, and the varying signal of the eye spot is thought to make one flagellum dominant in its beating, re-orienting the cell toward the light source. While dominance is broadly accepted, the underlying nature of dominance—changes in force, frequency, or synchrony—has yet to be determined. It has also yet to be directly demonstrated that this model accounts for phototaxis. We used a laser trap to capture free-swimming Chlamydomonas and measure the propulsive forces and beat frequencies generated by the flagella in the presence and absence of a directional light source. A 3D computational model of Chlamydomonas motility was developed using parameters measured in the laser trap. The data suggest that the most functionally significant change in the flagella in response to light is a waveform change in the trans flagellum that increases its lateral beat strength. The computational model shows that subtle changes in lateral beat strength are necessary and sufficient for phototaxis, and explains the conserved rotational rate of Chlamydomonas.

Morphology, molecular characterisation and systematic position of Hemiplectus muscorum Zell, 1991 (Nematoda: Plectida)

Abstract Hemiplectus muscorum, the type and single representative of its genus, is redescribed on the basis of abundant new material collected in the UK, Canada and the USA using both light and scanning electron microscopy. The phylogenetic relationships of the species are inferred from morphological as well as molecular data. Maximum parsimony, neighbour joining and maximum likelihood analyses of small subunit (SSU) rRNA sequences support a position nested among the Plectidae. This conflicts with our morphological assumptions of character polarity, as it implies that the absence of a valvate bulb in Hemiplectus is a reversal rather than a plesiomorphy. The excretory system of Hemiplectus is described more precisely. Its structure is highly reminiscent of the system in Plectus but differs in the presence of an anterior and posterior pair of pseudocoelomocytes flanking the renette cell. A pair of lateral somatic setae is identified as possible homologues of the 'deirids' in Plectus and Rhabditida. Measurements and descriptions are given of all four juvenile stages.

Epicardial development in lamprey supports an evolutionary origin of the vertebrate epicardium from an ancestral pronephric external glomerulus

The epicardium is the outer layer of the vertebrate heart. Both the embryonic epicardium and its derived mesenchyme are critical to heart development, contributing to the coronary vasculature and modulating the proliferation of the ventricular myocardium. The embryonic epicardium arises from an extracardiac, originally paired progenitor tissue called the proepicardium, a proliferation of coelomic cells found at the limit between the liver and the sinus venosus. Proepicardial cells attach to and spread over the cardiac surface giving rise to the epicardium. Invertebrate hearts always lack of epicardium, and no hypothesis has been proposed about the origin of this tissue and its proepicardial progenitor in vertebrates. We herein describe the epicardial development in a representative of the most basal living lineage of vertebrates, the agnathan Petromyzon marinus (lamprey). The epicardium in lampreys develops by migration of coelomic cells clustered in a paired structure at the roof of the coelomic cavity, between the pronephros and the gut. Later on, these outgrowths differentiate into the pronephric external glomerulus (PEG), a structure composed of capillary networks, mesangial cells, and podocytes. This observation is consistent with the conclusion that the primordia of the most anterior pair of PEG in agnathans have been retained and transformed into the proepicardium in gnathostomes. Glomerular progenitor cells are highly vasculogenic and probably allowed for the vascularization of a cardiac tube primarily devoid of coronary vessels. This new hypothesis accounts for the striking epicardial expression of Wt1 and Pod1, two transcription factors essential for development of the excretory system.