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Nuevos Datos Sobre Cuatro Especies De Ascidias De La ANALES DE BIOLOG~A,19 (Biología Animal, 8) 1993: 19-27 SECRETARIADO DE PUBLICACIONES - UNIVERSIDAD DE MURCIA NUEVOS DATOS SOBRE CUATRO ESPECIES DE ASCIDIAS DE LA FAMILIA PoLYCLINZDAE EN LA PEN~NSULAIB~RICA Elsa Vázquez y Victoriano Urgorri * Recibido: 22 marzo 1993 Aceptado: 12 enero 1994 SUMMARY New data about distribution of four species of ascidians of thepolyclynidae family in the Iberian Peninsula New data about the distribution of four species of ascidians in the Iberian Peninsula coast are given: Aplidium glabrum (Verri1.187 1) and Synoicum pulmonaria (Ellis & Solander, 1786) are recorded for the first time in Iberian Peninsula, Aplidium punctum (Giard, 1873) is recorded for the first time in the Spanish coast and A. asperum (Drasche, 1883) for the Atlantic Iberian coasts. The tadpole lawae of A. glabrum is described for the first time and its northem distribution limit is enlarged. The synonymy between A. asperum and A. coeruleum is discussed. Key words: Aplidium, Synoicum, Polyclinidae, Ascidiaceae, description, distribution, Iberian Penin- sula. RESUMEN Se aportan nuevos datos sobre la distribución de cuatro especies de ascidias en las costas de la Penín- sula Ibérica: Aplidium glabrum (Verril, 1871) y Synoicum pulmonaria (Ellis & Solander, 1786) son nuevas citas en la Península Ibérica, Aplidium punctum (Giard, 1873) lo es en las costas españolas y A. asperum (Drasche, 1883) en las costas atlánticas ibéricas. Se describe por primera vez la lawa de A. glabrum y se amplía su límite de distribución meridional hasta nuestras costas. Se discute la sinonimia entre A. asperum y A. coeruleum. Palabras clave: Aplidium, Synoicum, Polyclinidae, Ascidiacea, descripción, distribución, Península Ibérica. INTRODUCCI~N que en las costas atlánticas ibéricas el conoci- miento se limita a ocho especies; RODR~GUEZ La familia Polyclinidae (Orden Aplouso- (19 14) menciona en Santander A. nordmanni branchiata) está representada en la Península (MILNEE DWARDS, 1841), Sidnyum argus (MIL- Ibérica por 32 especies, de las que 3 1 han sido NE EDWARDS, 1841) y S. elegans (GIARD, 1873); citadas en su vertiente mediterránea, mientras SALDANHA(1974) cita en Arrábida (Portugal) * Departamento de Bioloxía Animal, Facultade de Bioloxía, Universidade de Santiago, 15.706 Santiago de Com- postela (España). 20 E. VhZQUEZ -V. URGORRl ANALES DE BlOLOGh 19 (1993) Aplidium albicans (MILNEEDWARDS , 184 l), A. Los únicos ejemplares, recolectados en el densum (GIARD,1 872), A. nordmanni (MILNE mes de agosto, estaban inmaduros. EDWARDS, 184 1), A. pallidum (VERRILL,18 17), A. asperum se encuentra en niveles infraii- A. punctum (GIARD, 1873), Sidnyum argus torales entre 7 y 10 m, en estaciones batidas, (Milne Edwards, 1841 ), S. eíegans (0, ocupando paredes verticales y rizoides de La- 1873) y A. proliferum (MILNE EDWARDS,184 1 ), minaria. siendo A. proliferum (MILNE EDWARDS, 184 1 ) la única especie citada en las costas de Galicia (Lugo) (POLO et al., 1982). Discusión Durante el periodo 1987-90 se realizaron en la Ría de Ferrol (Galicia), numerosos mues- Aplidium asperum y Aplidium coeruleum treos encaminados al estudio de la ascidiofau- han sido clásicamente consideradas como espe- na, obteniendose un total de 64 especies cuatro cies diferentes fundamentándose en un único de las cuales, Aplidium asperum, A. glabrum, carácter, la forma del sifón atrial. Según VON A. punctum y Synoicum pulmonaria, son obje- DRASCHE(1 883), el sifón atrial de A. asperum to de este trabajo. sería un corto tubo con los bordes lobulados, opinión mantenida por autores posteriores (LA- HILLE, 1890; DAUMEZON,1909; HARANT& VER- RESULTADOS NIERES, 1933, mientras que el sifón atrial de A. coerulewn sería una amplia abertura situada Aplidium asperum Drasche, 1883 entre la 4" y la 5" fila de estigmas. PERES(1959) Aplidium coeruleum Lahiiie, 1890 cuestiona la validez del carácter sistemático Aplidium coeruleum var. argelensis Bré- que separa las dos especies, ya que la forma tu- ment, 1912 bular del sifón atriai se debería a un estado de contracción de los zooides, opinión sostenida por autores posteriores (TuR~N,1987a; RAMOS, Material examinado 1988). Los zooides de las colonias estudiadas están Ría de Ferrol: Punta do Segaño (43' 27' 14" muy contraídos mostrando claramente el sifón N; 08' 18' 46" W), 17-08-88: cinco colonias. atrial la forma de tubo (Fig. 1 C y D). Se exami- naron también ejemplares de ambas especies en Descripción la colección del Museum National d'Histoire Naturelle de Paris donde los zooides de Apli- Colonias planas, la mayor de 4x30~10mm dium asperum se encontraban contraídos ob- y la menor de 2x1 7x1 0 mm, lobuladas con la servándose claramente el sifón atrial en forma superficie lisa; la túnica es de consistencia gela- de tubo, mientras que el ejemplar asignado a A. tinosa con alguna incrustación de arena. Colo- coeruleum (colección FIALA-MEDIONI)estaba ración naranja pero sin la tonalidad azulada en relajado y presentando la abertura neta, grande el sifón bucal que señalan otros autores (HA- y sin formar tubo. Además se estudiaron varias RAhT & VERNIERES,1933; TUR~N,1987a; RA- colonias de A. coeruleum recolectadas en Ban- MOS, 1988). yuls-sur-Mer, las que, tras grados diferentes de Zooides formando sistemas alargados y anestesia, se obtuvieron zooides con distintos serpentiformes y con el sifón bucal con 6 1ó- grados de contracción (Fig. 1 A y B); los anima- bulos. La branquia posee 9 filas de estigmas les bien relajados no presentaban sifón como fi- en las colonias recolectadas en la Ría de Fe- gura FIALA-MEDIONI(1970), pero con grados rrol y 11 filas en las recolectadas en Banyuls- diferentes de relajación, el estado de contrac- sur-Mer (Francia). El sifón atrial es un corto ción de los zooides era mayor, adquieriendo tubo circular, con el borde algo lobulado, sin gradualmente el sifón cloaca1 la forma de tubo. lengüeta y que se abre a nivel de la 5" fila de Esto corrobora la opinión de PERES(op. cit.) y estigmas. Estómago con 12 a 14 pliegues lon- autores posteriores que consideran A. coeru- gitudinales. leum como un sinónimo de A. asperum. ANALES DE BIOLOG~A,19 (1993) NUEVOS DATOS SOBRE CUATRO ESPECIES DE ASCIDIAS 21 Distribución del intestino es muy variable dependiendo del Esta especie está ampliamente repartida grado de contracción del zooide y de la presen- por las costas europeas del Océano Atlántico y cia de heces. el Mar Mediterráneo. En las costas del medite- Las gónadas se encuentran en el post-abdo- rráneo ibérico ha sido citada en Baleares (PE- men con el ovario situado debajo del asa intes- tinal y los testículos, biseriados, debajo del ova- RES, 1957; RAMOSet al., 1991 ), Gerona (RA- rio. MOS, 1984; TURON, 1985 y 1987b; LAFARGUE et al., 1986), Valencia (DAUMEZON,1909), Ali- Las larvas, que miden 640 pm de largo y cante (RAMOS, 1988), Alborán (PERES,1959) y 620 pm de ancho, presentan 3 papilas adhesi- vas y 6 pares de ampollas laterales de fijación Estrecho de Gibraltar (RAMOS et al., 1992) por lo que los ejemplares estudiados representan la bastante pequeñas y que, en las larvas más de- primera cita en el litoral atlántico ibérico. sarrolladas, se dividen en numerosas vesículas parietales. El tegumento de la lawa está cubier- to de puntos blancos. La cola rodea al tronco Aplidium glabrum (VERRILL, 1871 ) completanlente. Amaroucium glabrum (VERRILL,187 1 ) Amaroucium translucidwn (HARTMEYER, Observamos gónadas y larvas en los meses 1903) de mayo y octubre. Aplidium ftavum (HARTMEYER,1903) A. glabrum es una especie de niveles medios e inferiores del mesolitoral en estaciones bati- Material examinado das y semibatidas. Ría de Ferrol: Punta Barbeira (43°28'08"N; Discusión 08°19'08 "W), 25- 1 0-88: una colonia. Ensena- da de Cariño (43O28'17"N; 08°18'58"W), 15- El zooide figurado por THOMPSON(1 934), 5-88: tres colonias. según HARTMEYER( 1923), presenta bolsa incu- batriz y los pliegues del estómago divididos Descripción mientras que en la descripción de VAN NAME (1945) no se observa ni bolsa incubatriz ni plie- Las colonias (Fig. 2 A y B) son de pequeño gues divididos, además de un abdomen mucho tamaño de 20x10 mm y globosas, de color na- más largo que en la descripción de THOMPSON ranja que le confieren los zooides, y con la túni- (1934). Posteriormente BERRILL (1950) descri- ca traslúcida algo dura. La relación entre el tó- be Aplidium glabrum, mezclando ambas des- rax, abdomen y post-abdomen (en estado de cripciones y dibujos, que, en nuestra opinión, contracción y con las gónadas no totalmente no pertenecen a la misma especie por los carac- desarrolladas) es 1: 1 : 1. teres anteriormente señalados. El sifón bucal está dividido en seis Ióbulos Estas colonias corresponden a la descrip- en la mayoría de los individuos y excepcional- ción de VAN NAME(1 945), aunque este autor mente en 8 lóbulos bucales dentro de una mis- no reseña ningún zooide con 8 lóbulos bucales. ma colonia; a veces puede presentar pequeñas Por este caracter (8 Ióbulos bucales), unido a la lobulaciones intermedias. La branquia está for- estructura del estómago con 20 plieges más o mada por 8 ó 9 filas de estigmas (debido al es- menos divididos, podría asemejarlos a Sidnyum tado de contracción de los zooides no nos fue elegans. No obstante, el número de filas de es- posible contar los estigmas por hemifila). El si- tigmas, la lengüeta atrial con 2 lóbulos en la fón atrial se abre a la altura de la 2" o de la 3" base y las vesículas parietales de las larvas los fila de estigmas; su borde está ligeramente lo- diferencian de esta especie. bulado, formando en algunos ejemplares un corto tubo; la lengüeta atrial es, o bien simple o Distribución bien trilobulada, con los lóbulos laterales en la base y de muy pequeño tamaño.
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