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1.
J Insect Sci ; 16(1)2016.
Artigo em Inglês | MEDLINE | ID: mdl-27538415

RESUMO

Several taxa of insects evolved a tympanate ear at different body positions, whereby the ear is composed of common parts: a scolopidial sense organ, a tracheal air space, and a tympanal membrane. Here, we analyzed the anatomy and physiology of the ear at the ventral prothorax of the sarcophagid fly, Emblemasoma auditrix (Soper). We used micro-computed tomography to analyze the ear and its tracheal air space in relation to the body morphology. Both tympana are separated by a small cuticular bridge, face in the same frontal direction, and are backed by a single tracheal enlargement. This enlargement is connected to the anterior spiracles at the dorsofrontal thorax and is continuous with the tracheal network in the thorax and in the abdomen. Analyses of responses of auditory afferents and interneurons show that the ear is broadly tuned, with a sensitivity peak at 5 kHz. Single-cell recordings of auditory interneurons indicate a frequency- and intensity-dependent tuning, whereby some neurons react best to 9 kHz, the peak frequency of the host's calling song. The results are compared to the convergently evolved ear in Tachinidae (Diptera).


Assuntos
Percepção Auditiva , Sarcofagídeos/fisiologia , Sarcofagídeos/ultraestrutura , Animais , Dípteros/fisiologia , Dípteros/ultraestrutura , Feminino , Microscopia Eletrônica de Varredura , Neurônios Aferentes/fisiologia , Órgãos dos Sentidos/fisiologia , Órgãos dos Sentidos/ultraestrutura , Limiar Sensorial , Microtomografia por Raio-X
2.
Zookeys ; 835: 65-86, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31065223

RESUMO

The present study aims to clarify the confused taxonomy of Z.schaufussi von Frauenfeld, 1862 and Zospeumsuarezi Gittenberger, 1980. Revision of Iberian Zospeum micro snails is severely hindered by uncertainties regarding the identity of the oldest Iberian Zospeum species, Z.schaufussi von Frauenfeld, 1862. In this paper, we clarify its taxonomic status by designating a lectotype from the original syntype series and by describing its internal and external shell morphology. Using SEM-EDX, we attempt to identify the area of the type locality cave more precisely than "a cave in Spain". The shell described and illustrated by Gittenberger (1980) as Z.schaufussi appears not to be conspecific with the lectotype shell, and is considered a separate species, Z.gittenbergeri Jochum, Prieto & De Winter, sp. n. Zospeumsuarezi was described from various caves in NW Spain. Study of the type material reveals that these shells are not homogenous in shell morphology. The holotype shell of Z.suarezi is imaged here for the first time. The paratype shell, illustrated by Gittenberger (1980) from a distant, second cave, is described as Zospeumpraetermissum Jochum, Prieto & De Winter, sp. n. The shell selected here as lectotype of Z.schaufussi, was also considered a paratype of Z.suarezi by Gittenberger (1980). Since this specimen is morphologically very similar to topotypic shells of Z.suarezi, the latter species is considered a junior synonym of Z.schaufussi (syn. n.). The internal shell morphology of all these taxa is described and illustrated using X-ray Micro Computer Tomography (Micro-CT).

3.
Zookeys ; (795): 1-12, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30429653

RESUMO

Five years ago, the Panamanian evolutionary lineage (EL) C12 was uncovered along with four other ELs in an integrative phylogenetic investigation of worldwide Carychiidae. Since EL C12 lacked shell material post-molecular analysis to serve as a museum voucher, it remained undescribed. Now, after recent collection efforts of C12 and the congener, Carychiumzarzaae Jochum & Weigand, 2017 at their original Panamanian sites, C12 is morphologically described and formally assigned the name, Carychiumpanamaense Jochum, sp. n. In sync with recent taxonomic treatment of the genus, computed tomography (CT) is used in this work to differentiate shells of C.panamaense sp. n. from geographically-proximal, Caribbean, North and Central American congeners. Recent material of topotypic Carychiumjardineanum (Chitty, 1853) and undamaged C.zarzaae were additionally CT-scanned and assessed in the comparative analyses.


Resumen Hace cinco años, el linaje evolutivo (LE) panameño C12 fue descubierto junto con otros cuatro LEs en un estudio filogenético integrativo mundial de Carychiidae. El LE C12 permaneció sin ser descrito dado que, después de los análisis moleculares, no había conchas disponibles que sirvieran como material de referencia en museos.Ahora, después de esfuerzos recientes para colectar C12 y el congénere, Carychiumzarzaae Jochum & Weigand, 2017 en los sitios panameños originales, C12 es descrito morfológicamente y se le asigna formalmente un nombre, Carychiumpanamaense Jochum, sp. n. De acuerdo con el tratamiento taxonómico reciente del género, en este trabajo se emplea tomografía computarizada (TC) para diferenciar conchas de C.panamaense sp. n. de congéneres geográficamente cercanos del Caribe, Norte y Centro América. Además, en el análisis comparativo se escaneó con TC y se examinó material reciente del topotípico Carychiumjardineanum (Chitty, 1853) y C.zarzaae en buen estado.

4.
Zookeys ; (675): 97-127, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28769681

RESUMO

Three new species of the genus Carychium O.F. Müller, 1773, Carychium hardiei Jochum & Weigand, sp. n., Carychium belizeense Jochum & Weigand, sp. n. and Carychium zarzaae Jochum & Weigand, sp. n. are described from the Southeastern United States, Belize and Panama, respectively. In two consecutive molecular phylogenetic studies of worldwide members of Carychiidae, the North and Central American morphospecies Carychium mexicanum Pilsbry, 1891 and Carychium costaricanum E. von Martens, 1898 were found to consist of several evolutionary lineages. Although the related lineages were found to be molecularly distinct from the two nominal species, the consequential morphological and taxonomic assessment of these lineages is still lacking. In the present paper, the shells of these uncovered Carychium lineages are assessed by comparing them with those of related species, using computer tomography for the first time for this genus. The interior diagnostic characters are emphasized, such as columellar configuration in conjunction with the columellar lamella and their relationship in context of the entire shell. These taxa are morphologically described and formally assigned their own names.

5.
Scanning ; 37(1): 63-72, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25639882

RESUMO

Repetitive freeze/thaw cycles lead to a progressive loss of structural and molecular integrity in deep frozen specimens. The aim of this study was to evaluate a micro-CT stage, which maintains the cryoconservation of large specimens throughout micro-CT imaging. Deep frozen ovine vertebral segments (-20 °C) were fixed in a micro-CT stage made of expanded polystyrene and cooled with dry ice (0 g, 60 g and 120 g). The temperature inside the stage was measured half-hourly over a time span of three hours with subsequent measurement of surface temperature. The method was validated in a series of 30 deep frozen vertebral specimens and in liver tissue after repetitive micro-CT scanning. Isolation without cooling resulted in defrosting. Cooling with 60 g of dry ice led to a temperature rise inside the stage (max. 5.1 °C) and on the specimen surfaces (max. -3 °C). Cooling with 120 g of dry ice resulted in a significant (p < 0.001) and sufficient lowering of the temperature inside the stage (max. -14 °C) and on the surface of the specimens (max. -13.9 °C). The surface temperature during the subsequent micro-CT validation study did not exceed -16 °C (processing time 1 h 45 min). The resolution was 33 µm isotropic voxel side length, enabling a binarization of bone microstructures. Temperature can reliably be maintained below -10 °C during a micro-CT scan by applying the described technique. The resulting spatial resolution and image quality permits a binarization of bone microstructure.


Assuntos
Congelamento , Manejo de Espécimes/métodos , Coluna Vertebral/diagnóstico por imagem , Microtomografia por Raio-X/métodos , Animais , Fígado/diagnóstico por imagem , Ovinos , Temperatura
6.
Zookeys ; (410): 23-40, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24899848

RESUMO

A review of the microgastropod genus Systenostoma is provided. Thai and Malaysian species are transferred to a new genus, Angustopila (type species: Systenostoma tamlod Panha & Burch, 1999). A new subterranean Angustopila species is described here. Conchologically, the new species is most similar to the cave-dwelling, Thai A. tamlod (Panha & Burch, 1999). One Thai species (Systenostoma edentata) is transferred to the genus Hypselostoma. Vietnamese members remain in the genus Tonkinospira (nomen novum) for Systenostoma Bavay & Dautzenberg, 1908 (non Systenostoma Marsson, 1887). A comprehensive map of former Systenostoma species is presented. SEM and NanoCT images, including a video of A. huoyani sp. n. internal shell morphology, provide novel perspectives of the shells of Angustopila and of the scarcely known Vietnamese Tonkinospira species. The biology of these snails is not yet known but collection localities suggest a troglophilic ecology.

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