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Trapiche – Santa Rosa De Quíves, Canta - Lima.) UNIVERSIDAD NACIONAL MAYOR DE SAN MARCOS (Universidad del Perú, Decana de AMÉRICA) FACULTAD DE CIENCIAS BIOLÓGICAS ESCUELA ACADÉMICO PROFESIONAL DE CIENCIAS BIOLÓGICAS MICROTURBELARIOS DEL RÍO CHILLÓN (Trapiche – Santa Rosa de Quíves, Canta - Lima.) Tesis para optar al Título Profesional de Biólogo con mención en Zoología Bach. Jhoe Steve Reyes Pajuelo Lima – Perú 2016 UNIVERSIDAD NACIONAL MAYOR DE SAN MARCOS (Universidad del Perú, Decana de AMÉRICA) FACULTAD DE CIENCIAS BIOLÓGICAS ESCUELA ACADÉMICO PROFESIONAL DE CIENCIAS BIOLÓGICAS MICROTURBELARIOS DEL RÍO CHILLÓN (Trapiche – Santa Rosa de Quíves, Canta - Lima.) Tesis para optar al Título Profesional de Biólogo con mención en Zoología Bach. Jhoe Steve Reyes Pajuelo. Asesor: Ruperto Severino López. Lima – Perú 2016 A los que recorrieron este sendero conmigo; algunos de ellos no se encuentran hoy con nosotros, pero guardan y guían nuestros pasos desde el todo… AGRADECIMIENTOS. Quiero expresar mis más sinceros y profundos agradecimientos a las personas que estuvieron involucradas directa o indirectamente en la preparación de esta obra. A Nicolás Tarmeño y Gisella Gómez, por la camaradería, confianza y aliento brindado durante toda la preparación de la tesis. A Isabel Centeno, por contar con su compañía y apoyo durante las campañas de muestreo. A mis amigos: Roberto Huanaco, por su grata compañía y por haberse ofrecido desinteresadamente a colaborar conmigo en varias salidas de campo. A Miguel Durand, por los consejos y la asistencia en la determinación de especies de plantas y manejo de coordenadas geográficas. A los Doctores Ernest Schockaert, Tom Artois, Niels Van Steenkiste, Carolina Noreña, Cristina Damborenea por sus acertados comentarios y por facilitarme referencias bibliográficas especializadas. Al Dr. Francisco Brusa, por la muy buena predisposición, comprensión y valiosa dirección en los procedimientos de estudio y determinación de especies. A Fernando Tapia, por la confianza, buena disponibilidad y préstamo de equipos para la medición de los parámetros fisicoquímicos del agua. Al profesor Carlos Mendoza, por la confianza y facilidades para utilizar los equipos de microscopía. A mi grata amiga, Abigail Gutierrez, por contactarme con especialistas en la preparación de cortes histológicos. A Emily Valle, por la paciencia y esfuerzo para la realización de los cortes histológicos. A Isabel Gamboa, por la ayuda, asesoramiento e ideas frescas durante el desarrollo de la tesis. A Joselyn Seminario, por la determinación de especies de macrófitas. A la profesora Lidia Sánchez, por las referencias bibliográficas y comentarios en las versiones iniciales del proyecto de tesis. A Luis Moreno, Augusto García, Ángel Romaní y Brian Tinoco; integrantes del Departamento de Helmintología del Museo de Historia Natural, por hacer más agradable mi paso por esta institución. A la Doctora Irma Franke, por la enorme ayuda con la traducción de textos del idioma alemán al español. A Karen Velázques y Diana Moreno, por traducir artículos científicos del idioma francés al español. A Rubí Navarro, por las esporádicas pero largas y profundas charlas aunadas de gran cariño y motivación. A G.M.M por el aliento y motivación constante para llevar a término la tesis. A Pandora, por la compañía, camaradería, complicidad y, las gratas y aleccionadoras enseñanzas que muy a su estilo sabe propinar. Al profesor Ruperto Severino, por toda la paciencia, buen ánimo, compresión, apoyo constante y motivadoras charlas durante el desarrollo de la tesis; por haberse portado como un segundo padre y haber sabido enseñar más de lo que corresponde como profesional y ser humano. Y un especial agradecimiento a Walter Reyes y María Pajuelo, mis padres, quienes fueron los pilares fundamentales para que todos mis ideales, sueños y anhelos se llevaran a cabo y concretaran de la mejor manera posible. Padre, sin haberlo deseado, me encaminaste hacia el estudio de los turbelarios; Gracias. A Diana Reyes, mi hermana, por los gratos momentos y saberme sacar carcajadas en los momentos menos esperados. Los mencionados aquí ya pueden ir felicitándose por todo el apoyo brindado y porque obras como esta no se logran todos los días. Bromas aparte, les agradezco infinitamente todo el respaldo brindado. ABREVIATURAS ac: Atrio común. acm: Aparato copulador masculino. ad: Abertura distal. af: Atrio femenino. ags: Atrio genital superior. agi: Atrio genital inferior. ali: Apéndices lobulares internos. am: Atrio masculino. ap: Abertura proximal. au: Aurículas. b: Boca. bc: Bolsa copuladora. bf: Bolsillo faringeal. bp: Bulbo del pene. cb: Canal de la bolsa. ce: Ducto eyaculador. cgc: Canal genital común. cgf: Canal genital femenino. col: “Cola”. cr: Cuerpos refringentes. cvp: Cavidad prefaringeal. de: Ducto espermático. dbi: Ducto bursointestinal. ea: Extremo anterior del cuerpo. ec: Epidermis ciliada. ep: Extremo posterior del cuerpo. eg: Huevo. epi: Epitelio cilíndrico infraciliado. ex: Excretóforos. f: Faringe. fc: Fosetas ciliadas. fvs: Falsa vesícula seminal. g: Gonoporo común. ga: Glándulas adherentes. gc: Glándulas de la cáscara. ge: Glándulas eritrofílicas. gf: Glándulas faringeales. glf: Glándulas frontales. gmv: Germovitelario. gn: Ganglio nervioso. gna: Ganglio nervioso anterior. gnp: Ganglio nervioso posterior. gp: Glándulas prostáticas. gv: Glándulas vitelógenas. i: Intestino. lp: Línea de pigmento refringente. mb: Membrana basal. mc: Músculo circular. ml: Músculo longitudinal. mr: Músculos retractores de la faringe. np: Nefridioporo. o: Ocelos. ov: Ovario. ovi: Oviducto. pa: Papilas adhesivas. pbs: Probóscide. pd: Proyecciones digitiformes. pf: Papilas faringeales. pgf: Gonoporo femenino. pgm: Gonoporo masculino. pp: Papila del pene. pse: Pigmento subepidérmico. pt: Protonefridio. rh: Rhabditos. ri: Ramas intestinales. rs: Receptáculo seminal. sd: Superficie dorsal. st: Estilete. sv: Superficie ventral. t: Testículos. tc: Tejido conectivo. ut: Útero. val: Valvas. vd: Vasos deferentes. vg: Vesícula granulosa (prostática). vit: Viteloductos. vs: Vesícula seminal. ÍNDICE GENERAL. Pág. 1. INTRODUCCIÓN .................................................................................................. 1 2. MARCO TEÓRICO................................................................................................ 3 2.1. Los “Turbellaria” ............................................................................................. 3 2.1.1. Sistemática .................................................................................................. 3 2.1.2. Epidermis, Estructuras Secretorias y Pared del Cuerpo .............................. 4 2.1.3. Musculatura ................................................................................................. 6 2.1.4. Parénquima ................................................................................................. 6 2.1.5. Regeneración .............................................................................................. 7 2.1.4. Sistema Nervioso y Órganos de los Sentidos .............................................. 8 2.1.5. Sistema Digestivo ........................................................................................ 9 2.1.6. Sistema excretor y Osmorregulación ..........................................................11 2.1.7. Sistema Reproductor ..................................................................................12 2.1.8. Ectosimbiosis .............................................................................................15 2.2. Distribución de Microturbelarios en Sudamérica............................................15 2.3. Revisión del Estado Actual del Conocimiento de Microturbelarios para el Perú ……………………………………………………………………………………….17 3. OBJETIVOS .........................................................................................................20 3.1. GENERAL .....................................................................................................20 3.2. ESPECÍFICOS ..............................................................................................20 4. MATERIALES Y MÉTODOS ................................................................................21 4.1. Área de Muestreo ..........................................................................................21 4.1.1. El río Chillón ...........................................................................................21 4.2. MATERIALES ...............................................................................................22 4.2.1. De Campo ..............................................................................................22 4.2.2. De Laboratorio .......................................................................................23 4.2.3. Procesamiento de información obtenida ................................................23 4.3. MÉTODO ......................................................................................................23 4.3.1. Colecta y Fijación ...................................................................................24 4.3.2. Identificación Taxonómica ......................................................................31 4.3.3. Descripción de Taxa ..............................................................................33 4.3.4. Búsqueda de reportes de especies. .......................................................34 5. RESULTADOS .....................................................................................................35 5.1. Parámetros Fisicoquímicos ...........................................................................35
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