Infestation with intradermal and subhipodermic larvae of the mite Hannemania sp. (Acari: Leeuwenhoekiidae) in anurans of the Province of Salta, Argentina

Hannemania (Acari: Leeuwenhoekiidae) es un género de ácaros cuyos adultos no son parásitos, sin embargo sus larvas parasitan a anuros y salamandras y su presencia causa desequilibrios en la estructura tegumentaria. Las especies de este género tienen una amplia distribución desde Estados Unidos hasta la Argentina, y en nuestro país están citadas para el litoral, el centro y el sur del país y una para la región andina de la provincia de Salta. El objetivo del trabajo fue evaluar la presencia de estos ácaros en anuros de las llanuras antropizadas de la región chaqueña de Salta (Argentina), su impacto histopatalógico sobre el tegumento y los parámetros de infestación. Se analizaron especímenes de la familia Leptodactylidae: Leptodactylus chaquensis y Leptodactylus bufonius y de la familia Phyllomedusidae: Pithecopus azureus, obtenidos en una estación agrícola ganadera del Departamento de Anta (Salta). Los ejemplares fueron recolectados manualmente, anestesiados, fijados en formaldehído al 10% y conservados en alcohol 70º. Se revisaron mediante microscopio estereoscópico para detectar la presencia de ácaros por elevaciones del tegumento, se realizaron análisis histológicos, se tomaron fotografías de microscopía óptica y electrónica de barrido, se contabilizaron las larvas en cada hospedador y se calcularon la prevalencia y la abundancia e intensidad medias. Las larvas del ácaro se ubicaron intradérmica y subhipodérmicamente, siendo esta última localización descripta por primera vez. Las larvas parásitas de ácaros causan deformidades y afectan el desplazamiento del anfibio, esto podría alterar la capacidad para alimentarse y el comportamiento defensivo, y por lo tanto, la supervivencia de los individuos. Este trabajo representa el primer reporte de Hannemania sp. en anuros de la llanura chaqueña de Salta y el primero para un miembro de la Familia Phyllomedusidae.The adults of Hannemania (Acari: Leeuwenhoekiidae) are not parasites, but their larvae parasitize anurans and salamanders, and their presence cause imbalances in the tegumentary structure. Species of Hannemania have a wide distribution from the United States to Argentina, and in our country are reported for the littoral, center, and south of the country, and one for the Andean region of the province of Salta. The objective of this work was to evaluate the presence of these mites in anurans of the anthropized plains of the Chaco (Salta), their histopathological impact over the tegument, and the infestation parameters. The Leptodactylidae Leptodactylus chaquensis, and Leptodactylus bufonius, and the Phyllomedusidae Pithecopus azureus from an agricultural livestock station of Anta Department (Salta) were analyzed. The specimens were collected by hand, anesthetized, fixed in 10% formaldehyde and preserved in 70º alcohol. The specimens were examined by stereoscopic microscope to detect the presence of mites due to tegument elevations, histological analysis were done, photos of optic and scanning electronic microscopy were taken, and larvae were counted in each host. The larvae of the mite were intradermally and subhipodermally located, this latter location is being described for the first time for Hannemania. Additionally, information about prevalence, and medium abundance and intensity of infestation is included. Mite larvae cause deformities and affect the displacement of amphibians, this could alter the ability to feed, and the defensive behavior, and therefore the survival of individuals. This work represents the first report of Hannemania sp. in anurans of the Chaco plain of Salta and the first for a member of the Family Phyllomedusidae.Asociación Parasitológica Argentin

The endolymphatic sacs in embryos of Amphisbaena darwini

Endolymphatic sacs of amphibians and reptiles are usually located inside the cranial cavity, posterior to the brain and dorsal to the foramen magnum (Wever, 1978, 1985). They are connected with the sacculus of the inner ear by means of endolymphatic ducts that pierce the internal bony wall of the otic capsules.Fil: Mangione, Susana. Fundación Miguel Lillo; ArgentinaFil: Montero, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación Miguel Lillo. Dirección de Zoología. Instituto de Herpetología; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentin

Morfología de los estados preimaginales de Gonatopus bonaerensis, y consideraciones sobre la morfología interna de sus larvas inmaduras (Hymenoptera, Dryinidae)

The postembryonic stages of Gonatopus bonaerensis Virla (Dryinidae), parasitoid of planthoppers (Delphacidae) vectors of plant diseases in Argentina, are described. The external morphology pattern of the eggs and larval stages does not differ from other species of Gonatopodinae already known. The chaetotaxy of the head is described and compared with other well-known species. The studies on the internal anatomy put emphasis in the description of the tegument, cephalic lobes and alimentary canal. The morphology of the muscular pharynx and the sphincter between esophagus and gastric cavity of G. bonaerensis larvae (formerly located in the genus Dicondylus) differs thoroughly with that described for G. chilensis (Olmi) (formerly belonging to the genus Pseudogonatopus). These divergences allow us to infer that, mechanically, the form of feeding of both species is different, being passive in G. bonaerensis and active in G. chilensis; these differences impose the necessity to study other species to clarify the taxonomic position of both groups.Fil: Mangione, Susana. Fundación Miguel Lillo; ArgentinaFil: Virla, Eduardo Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentin

Occurrence and distribution of sesamoid bones in squamates: A comparative approach

Sesamoids are defined as skeletal elements that develop within a continuous band of regular dense connective tissue (tendon or ligament) adjacent to an articulation or joint. In this work, we discuss developmental data on two squamate species, provide data on the onset of the squamate sesamoids and the muscles they are associated to. Our results show that Mabuya mabouya and Liolaemus albiceps exhibited rather similar ontogenetic patterns and that the first sesamoids appear in embryos. The ossifying sesamoid timing is different between M. mabouya and L. albiceps, being faster in the former. In adults, we found 41 sesamoids, considering both fore and hindlimbs. We did not find any intrataxonomic differences, or any differences between the right and left side of the specimens in relation to the sesamoid presence. We recognize four types of sesamoids: (1) embedded sesamoids; (2) interosseus sesamoids; (3) glide sesamoids; and (4) supporting sesamoids. A table is included with a preliminary survey of the sesamoid distribution pattern in 10 Squamate clades.Fil: Jerez, Adriana de Los Angeles. Universidad Industrial Santander; Colombia. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Nturales. Instituto de Bio y Geociencias del Noa; ArgentinaFil: Mangione, Susana. Fundación Miguel Lillo; ArgentinaFil: Abdala, Virginia Sara Luz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Fundación Miguel Lillo. Dirección de Zoología. Instituto de Herpetología; Argentin

Morfología externa e interna de la larva de Chiasmocleis leucosticta (Boulenger, 1888) (Amphibia, Anura, Mycrohylidae).

This contribution reports a comprehensive study of the tadpole of Chiasmocleis leucosticta, including external morphology, and, for the first time in the genus, the analysis of the bucco-pharingeal cavity, chondrocranium, visceral skeleton and histology of a peculiar structure of the tail. After the comparisson with other species of the genus and diverse species of the family, some structures are remarcable: (a) The anterior portion of the head bears a symmetrical line, similar in structure to a lateral line and in position to an orbitonasal line or nasolacrimal groove; (b) chondrocranium and visceral skeleton show a mixture of character states reported as typical for Types II and IV larvae; (c) the base of the tail has, as happen in other microhylid tadpoles, a peculiar thickenning, result of a particular development of the caudal dermis; (d) in the buccal cavity, the prenarial papilla is absent, the arena of the buccal roof bears several paillae and the glottis is placed in such a way that the prelingual area is the best developed. As a result, the tadpoles of C. leucosticta resemble more to diverse Asian than to the Neotropical microhylid larvae.Fil: Langone, José A.. Museo Nacional de Historia Natural y Antropología; UruguayFil: Lavilla, Esteban Orlando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Echeverría, Dinorah Diana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: Mangione, Susana. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Segalla, Magno V.. Instituto Horus; Brasi

Delayed colorectal cancer care during covid-19 pandemic (decor-19). Global perspective from an international survey

Background The widespread nature of coronavirus disease 2019 (COVID-19) has been unprecedented. We sought to analyze its global impact with a survey on colorectal cancer (CRC) care during the pandemic. Methods The impact of COVID-19 on preoperative assessment, elective surgery, and postoperative management of CRC patients was explored by a 35-item survey, which was distributed worldwide to members of surgical societies with an interest in CRC care. Respondents were divided into two comparator groups: 1) ‘delay’ group: CRC care affected by the pandemic; 2) ‘no delay’ group: unaltered CRC practice. Results A total of 1,051 respondents from 84 countries completed the survey. No substantial differences in demographics were found between the ‘delay’ (745, 70.9%) and ‘no delay’ (306, 29.1%) groups. Suspension of multidisciplinary team meetings, staff members quarantined or relocated to COVID-19 units, units fully dedicated to COVID-19 care, personal protective equipment not readily available were factors significantly associated to delays in endoscopy, radiology, surgery, histopathology and prolonged chemoradiation therapy-to-surgery intervals. In the ‘delay’ group, 48.9% of respondents reported a change in the initial surgical plan and 26.3% reported a shift from elective to urgent operations. Recovery of CRC care was associated with the status of the outbreak. Practicing in COVID-free units, no change in operative slots and staff members not relocated to COVID-19 units were statistically associated with unaltered CRC care in the ‘no delay’ group, while the geographical distribution was not. Conclusions Global changes in diagnostic and therapeutic CRC practices were evident. Changes were associated with differences in health-care delivery systems, hospital’s preparedness, resources availability, and local COVID-19 prevalence rather than geographical factors. Strategic planning is required to optimize CRC care