In March 2020, in the context of the pandemic produced by the covid-19 outbreak that also affected higher education, using the Information and Communication Technologies (ICT) to resolve the situation. The impact, which caused the adjustment to virtuality, had obstacles and difficulties, as well as challenges and new competences, for teachers and students. In this work, the responses of first-year students of annual course, of the Faculty of Natural Sciences and Museum-UNLP, to the survey carried out at the end of the course, are analyzed. This analysis allows us to know the perceptions they had during the course in virtual mode, since, being the first time of this experience, it is important to know the opinions that allow us to improve teaching practices. This new form of teaching put into practice due to the particular health situation opens up a range of possibilities, including the possible implementation of a bimodal course.

A partir del mes de Marzo de 2020, en el contexto de la pandemia producida por el brote de covid-19 que afectó también a la educación superior, recurriendo al uso de las TecnologÃas de la Información y la comunicación (TIC) para afrontar la situación. El impacto, que provocó el ajuste a lo virtual, contó con obstáculos y dificultades, asà como, retos y nuevas competencias, para docentes y alumnos. En este trabajo se analizan las respuestas de les alumnos de primer año de una asignatura anual de la Facultad de Ciencias Naturales y Museo- UNLP, a la encuesta realizada al finalizar la cursada. Este análisis nos permite conocer las percepciones que tuvieron durante el desarrollo de la materia en modo virtual, ya que, al ser la primera vez de esta experiencia, es importante conocer las opiniones que nos permitan mejorar las prácticas docentes. Esta nueva forma de enseñanza puesta en práctica debido a la situación sanitaria particular, nos abre un abanico de posibilidades, incluyendo la posible implementación de una cursada bimodal.

Abstract Presence of the genus Neoparasitylenchus Nickle, 1967 (Tylenchida, Allantonematidae), parasitizing Harmonia axyridis (Pallas, 1773) (Coleoptera, Coccinellidae) in Argentina. We describe a new species Neoparasitylenchus platense sp. n., which is characterized by having the free living stages lip region flatly rounded, spear slender, faintly knobbed, tail rounded, females with light brown body, stylet not sunken into body, and not prominent, subterminal vulva and anus, obtusely rounded tail end, with a peg-like projection, oviparous, and the males with a little stylet and partially degenerate oesophagus, spicules filiform with widened base, short gubernaculum, leptodera bursa.

Resumen Se cita por primera vez el género Neoparasitylenchus Nickle, 1967 (Tylenchida, Allantonematidae), parásito de Harmonia axyridis (Pallas, 1773) (Coleoptera, Coccinellidae) para Argentina. Se describe la especie nueva Neoparasitylenchus platense sp. n. que se caracteriza por tener en las formas de vida libre la región labial rodeada de una estructura plana, estilete delgado, levemente curvado, apéndice caudal redondeado, hembras con cuerpo marrón claro, estilete no hundido en el cuerpo y no prominente, vulva y ano subterminal, apéndice caudal redondeado, con una proyección en forma de clavija, ovíparos. Los machos con un estilete y un esófago parcialmente degenerados, espículas filiformes con base ensanchada, gubernaculum corto, bursa leptodera.

Hexamermis bonaerensis sp. n. a parasite of Epilachna paenulata (Germar, 1824) (Coleoptera, Coccinellidae) from Argentina is described. It is characterized by having the amphids medium sized, rounded oval shaped, the vagina muscularized and slightly protruding with a descending branch forming a loop before joining the uterus. It presents three rows of genital papillae: the ventrolateral in one row with thirteen papillae; the ventral row with two single, three pairs and two single preanal papillae, and with five pairs postanal papillae.

Se describe a Hexamermis bonaerensis sp. n. un parásito de Epilachna paenulata (Germar, 1824) (Coleoptera, Coccinellidae) en Argentina. Se caracteriza por tener los anfídios de tamaño mediano y de forma oval redondeada. La vagina es musculosa y ligeramente protuberante, con una rama descendente que forma un asa antes de unirse al útero. Presenta tres hileras de papilas genitales: la ventrolateral en una hilera con trece papilas; la hilera ventral con dos papilas preanales simples, tres pares y dos preanales únicas, y con cinco pares de papilas postanales.

Parasitylenchus pseusobifurcatus sp.n. (Tylenchida, Allantonematidae) is described for the first time for Argentina as a parasite of adults of Harmonia axyridis (Pallas, 1773) (Coleopera, Coccinellidae). The new species is closed to P. bifurcatus Poinar Jr. & Steenberg, 2012, by the characteristic of having the tail tip of all vermiform females and immature males bifurcated, but they differ by the size of the gubernaculum. Its karyotype formula is described.

Se cita y describe por primera vez para Argentina Parasitylenchus pseusobifurcatus sp.n. (Tylenchida, Allantonematidae), parásito de adultos de Harmonia axyridis (Pallas, 1773) (Coleopera, Coccinellidae). Esta nueva especie está muy cercana a P. bifurcatus Poinar Jr. y Steenberg, 2012, por la característica de tener todas las hembras vermiformes y los machos inmaduros la punta del apéndice caudal bifurcada, pero se diferencian entre otros por el tamaño del gubernáculo. Se describe su fórmula cariotípica.

For the first time in Argentina, we report that in Harmonia axyridis Pallas, 1773, and Cycloneda sanguinea (Linnaeus, 1763) (Coleoptera, Coccinellidae) parasitizing by nematodes which belong to the family of Allantonematidae (Nematoda, Tylenchida). The genera are Metaparasitylenchus Wachek, 1955 (Nickle, 1967), Sulphuretylenchus Rühm, 1956 (Nickle, 1967) and Contortylenchus Rühm, 1956. They will be described and photographied afterwards.

Se cita por primera vez para la Argentina nemátodos parásitos de Harmonia axyridis Pallas, 1773, y Cycloneda sanguinea (Linnaeus, 1763) (Coleoptera, Coccinellidae), estos nemátodos pertenecen a la familia de Allantonematidae (Nematoda, Tylenchida). Los géneros hallados son Metaparasitylenchus Wachek, 1955 (Nickle, 1967), Sulphuretylenchus Rühm, 1956 (Nickle, 1967) y Contortylenchus Rühm, 1956. Se describen y fotografían.

Oryctophila bonaerensis sp. nov. parasitizing curculionid beetle larvae from Argentina, is described and illustrated. The species is characterized by a prominent genital cone and a short and filiform tail appendage. Female with vulva at midlenght of body, vagina long, S-shaped, monodelphic, opistodelphic. Male with one club-shaped spicule. Genital papillae arranged as follows: one pair of large preanal papillae and three pairs of postanal papillae of various sizes: a pair of medium sized papillae is immediately posterior to the anus, followed by a pair of large papillae, and one pair of small papillae at the base of the caudal appendage.

Thelastoma domesticus sp. nov. a parasite of nymphs of Periplaneta americana (Linneus, 1758) found in La Plata, Buenos Aires Province, Argentina is described and illustrated. This new species is characterized by having in the mouth a simple stoma with of thick walls, strongly cuticularised forming three pairs of nodules in two rows, without teeth; the excretory pore is located posterior to the beginning of the intestine, the male presents particular distribution of the genital papillae: a pair of big papillae preanal and three pairs of papillae posanales grouped very close, the second pair of papillae are displased a bit laterally, forming with other posanal papillae a circle.

Thelastoma domesticus sp. nov. se halló parasitando a ninfas de Periplaneta americana (Linnaeus, 1758) en la ciudad de La Plata, Província de Buenos Aires, Argentina, en el presente trabajo se describe e ilustra. Esta especie nueva se caracteriza por tener en la boca un estoma simple de paredes gruesas, fuertemente cuticularizada formando tres pares de nodulos en dos filas, sin dientes, el poro excretor es posterior, se ubica al comienzo del intestino, el macho presenta una distribución particular de las papilas genitales: un par grande de papilas preanales y tres pares posanales agrupadas, de las cuales el segundo par se encuentra desplazado lateralmente, configurando así con las otras papilas posanales un círculo.

Blatticola cristovata n. sp. (Oxyurida, Thelastomatidae) a parasite of the cricket Anurogryllus muticus (De Geer, 1773) (Orthoptera, Gryllidae) from Argentina, is described and illustrated. This is the first species of the genus Blatticola found parasitizing cricket. This new species is characterized in females by having the cuticle annulated through the body length, the mouth opening is subtriangular and surrounded by eight cephalic papillae, the stoma is short with three pairs placed in two rows of cuticular sclerotised plates, amphids in small pore shaped, oesophagus is divided into three parts, anterior cylindrical corpus, isthmus distinct, and basal bulb valved, the nerve ring is situated around the middle of corpus, the intestine is wide broad anteriorly, oval eggs, smooth shell, with a straight side, and the other side with a band running longitudinally. Males with one pair of preanal, one pair of adanal and two pairs of postanal papillae, and the tail appendage short, conical and pointed.

Una nueva especie Blatticola cristovata n. sp. (Oxyurida, Thelastomatidae) parásita del grillo Anurogryllus muticus (De Geer, 1773) (Orthoptera, Gryllidae) en Argentina, se describe e ilustra. Esta es la primera especie del género Blatticola que se encontró parasitando a grillos. Esta nueva especie se caracteriza por tener las hembras la cutícula anillada a lo largo de todo el cuerpo, la abertura bucal triangular rodeada por ocho papilas cefálicas, el estoma corto con tres pares de placas esclerotizadas dispuestas en dos líneas, anfidios pequeños en forma de poro, esofago dividido en tres partes, una anterior con un corpus cilíndrico, un istmo distintivo, y un bulbo basal con valvas, el anillo nervioso situado rodeando el corpus, el intestino ensanchado anteriormente, huevos ovales, de cáscara lisa, con un lado recto y el otro con una cresta longitudinal. Macho con un par de papilas preanal, uno adanal y dos pares de papilas postanales, y apéndice caudal corto, cónico y punteagudo.

Uma espécie nova do gênero Cephalobium (Nematoda, Cephalobiidae), parasita de Anurogryllus muticus (De Geer) (Ortoptera, Gryllidae) de Gorina, La Plata, Argentina, é descrita e ilustrada. Este nematoda pode ser caracterizado por apresentar estoma mais longo que largo, o aparelho glottoideo anisoglottideo e anisomórfico, dividido em duas porções, uma com paredes quitinizadas e a outra com três dentes dorsais simples. O macho possui espículas longas e separadas e o gubernáculo curto sem qualquer projeção. As papilas genitais estão organizadas em cinco pares pós-anais.

A new species of Cephalobium from Gorina, La Plata, Argentina, parasiting nymphs of Anurogryllus muticus (De Geer) (Orthoptera, Gryllidae) is described and illustrated. This nematode can be characterized by having the stoma longer than broad, the glottoid apparatus anisoglottid and anisomorphic, divided into two portions, one with cuticularized walls and the other with three simple dorsal teeth. The male is further characterized by the presence of two long and separated spicules and short gubernaculum without any projection. Genital papillae are arranged in five postanal pairs.

Three new species of Cephalobium Cobb, 1920, C. laplata from City Bell, C. polidentatum from Lincoln and C. dispar from Gorina, parasites of Gryllodes laplatae Saussure, 1877 from Buenos Aires, Argentina, are described and illustrated. Cephalobium laplata can be differentiated by having the cheilostom with a dorsal unmovable tooth, telostom with three ventral little teeth and two ventral movable claw teeth and gubernaculum triangular and five pairs of genital papillae. Cephalobium polidentatum has cheilostom with a movable ventral tooth, prostom with four dorsal movable teeth and telostom with three teeth; gubernaculum triangular with projections and with one pair of preanal and six pairs of postanal papillae. Cephalobium dispar is characterized by having telostom with two wings around the spicules and one pair of preanal and six pairs postanal papillae.

Gryllophila cephalobulata n. sp. (Nematoda, Thelastomatidae) a parasite of the mole cricket Neocurtilla claraziana (Orthoptera, Gryllotalpidae) isolated in Buenos Aires Province, is described and illustrated. It is characterized by cuticle annulated all along the length of the body; the first ring has 4 lobules, the second one has 14 lobules, the others rings are simple, the stoma is short and has 4 small teeth, the genital papillae are arranged in 5 pairs, of which 3 pairs are preanal and 2 pairs are postanal. The tail appendage of the male is long and filiform.

Neyraiella distinctus n. sp. was found parasitizing nymphs of the cricket Gryllodes laplatae Sauss in City Bell, Argentina. This species was characterized by having the excretory pore in the posterior end of the basal bulb, vulva protruding with one lip well developed in the 1/3 end of the body, anus of the female with wings, male with a single spicule without any sculpture, gubernaculum and bursa are absent, six pairs of genital papillae arranged in two preanal pairs, one adanal pair and three postanal pairs, and the tail appendage in both sexes was short and conic.

Severanoia brevicauda n. sp., a parasite of larvae of Diloboderus abderus in Argentina, is described and illustrated. It can be characterized by having the vulva situated at the posterior middle of the body, the eggs without sculpture, the male with three pairs of genital papillae of which one pair is preanal and two pairs postanal. The tail appendage in both sexes is short.

Cameronia laplatae n. sp. found in City Bell, Argentina, parasitizing crickets is described and illustrated. The new species is distinguished from other members of the genus Cameronia by the distribution pattern of the genital papillae in the male. It differs from all congeners mainly in having two pairs preanal y two pairs postanal papillae

Cephalobium bidentatum sp. nov., parasitizing nymphs of Gryllodes laplatae Sauss (Orthoptera, Gryllidae) from Argentina, is described and illustrated. It is distinguished from other members of the genus Cephalobium COBB, 1920, by having the buccal cavity very sclerotized with two hook-shaped teeth, vagina short and muscular, male has two spicules with hook-shaped tips, and by the distribution pattern of the postanal papillae: one pair under the anus, three pairs between the anus and the tail, and two pairs at the base of the tail appendage.