Bijdragen tot de Dierkunde, 54 (1): 101-126 — 1984 On the species of the Duges ia gonocephalagroup (Platyhelminthes, Turbellaria, Tricladida) from Greece by Elizabeth J. de Vries Institute of Taxonomie Zoology, University of Amsterdam, P. 0. Box 20125, 1000 HC Amsterdam, The Netherlands Summary The of groups or superspecies. status Dugesia of and is the the genus, Dugesia gonocephala a species group, comprising gonocephala, type-species which differ from each the best has numerous closely related species, supposedly one known, previously other in and In this re-assessed Vries morphological karyological aspects. been (De & Ball, 1980). known and described ofthe paper presently species, group The family Dugesiidae, of which Dugesia is from the eastern Mediterranean region, are reviewed. the type-genus, was erected by Ball (1974a) who Hitherto the triclads ofthis region have been poorly known also made the first strict in with Yet there is phylogenetic analysis comparison their western counterparts. of the Within the it a wealth of species in the area. Six well-delimited new group. genus Dugesia as was of the described and species Dugesia gonocephala group are then known, Ball recognized a number of one further species is rescued from The wealth synonymy. units which he phylogenetic gave subgeneric of material available has also made possible an assessment rank. One of the largest of these was the of the taxonomic of characters con- validity many usually sidered be of within this difficult nominate to importance group. subgenus, Dugesia, exemplified by Dugesia gonocephala and its allies. Résumé In his phylogenetic revision, Ball (1974a) that each of the de suggested subgenera recognized Dugesia gonocephala est un groupe d’espèces, contenant distin- him was of rank but that nombreuses espèces étroitement apparentées, se by worthy generic de l’autre au de vue et elevation guant l’une point morphologique should await a thorough analysis of Dans le article les karyologique. présent on passe en revue each This he has for the group. done genera du décrites espèces groupe connues ou comme nouvelles, Neppia (Ball, 1974b) and Spathula (Ball, 1977). de la région est-méditerranéenne. Jusqu’à présent les Now research is being carried out in Amster- Triclades de cette région restaient mal connus en com- dam in the of the avec néanmoins hope paraison ceux occidentaux; cette région se elucidating phylogenetic abondance On décrit six and caractérise par son d’espèces. status of, phylogenetic relationships within, espèces nouvelles bien délimitées du groupe Dugesia the subgenus Dugesia, especially the D. gonocephala, et une autre espèce, considérée auparavant s.l. is gonocephala group. Dugesia gonocephala a ici validée. L’abondance du comme synonyme, est a number of matériel aussi créé la de vérifier la superspecies, comprising closely disponible a possibilité related which resemble each other in validité taxonomique de plusieurs caractères qui sont species ex- dans ternal but differ from in généralement regardés comme importants ce groupe appearance, each other difficile. internal and of their anatomy aspects karyology within (Benazzi, 1955). The taxonomy this group has proved to be complicated. This is INTRODUCTION because here with of we are dealing a group This is of series towards related paper one a leading a phylogenetically closely species, of revision of the sensu which some have evolved than phylogenetic genus Dugesia species more stricto, the of the others. There are several that type-genus family Dugesiidae. species possess Distributed throughout the Old World this markedly different features in their copulatory has been divided into number of so that their identification genus a species apparatus, poses no Downloaded from Brill.com10/07/2021 01:01:34PM via free access 102 - E. J. DE VRIES DUGESIA GONOCEPHALA FROM GREECE whereas other difficulties, species are very welcomed of studying an extensive triclad col- similar to each other, differing only in details, lection from the fresh waters of the Mediterra- for the making it hard nonspecialist to nean region. The specimens were collected by distinguish them. Dr. H. Malicky of the Biological Station of Species of the gonocephala group occur Lunz, Austria, as a part of an ecological survey the Old World. Several deal of the Mediterranean from throughout papers region. Apart a with members of the from number of the group specific species already known, samples contained several of the D. geographical areas. The Asiatic species were new species discussed Ball and Kawakatsu from Greece the Greek by (1970) by et gonocephala group and al. has In materialfrom several (1976). Lepori (1951) given an account islands. addition, new of the Mediterranean known Greek which in western species at localities, was already present that time, and Dahm (1971) has dealt with the the Zoölogisch Museum, Amsterdam, has been African Vries Ball studied. The representatives. De & (1980), new species are here described, their taxonomie assessed and and more recently De Vries (in prep.), have re- position the D. from used assessed the status of gonocephala s. str. validity of some commonly taxonomie European locations. characters discussed. In order obtain the into to necessary insight Moreover, it is here felt that workers in this the of variation within the will benefit from range morphological geographic area a complete number of from different overview of the of the group, a large species species gonocephala group studied. As result in this Therefore the geographical regions were a occurring area. descrip- it became that the triclad of this study apparent tions of D. cretica and D. gonocephala s. str. (sensu of of the Mediterranean Vries also included. In fauna a large area was De & Ball, 1980) are this still unknown. It is that the Italian the of the entire true penin- way paper serves as a synopsis in sula and the Italian islands are relatively well subgenus Greece. analysed, due to the work of Benazzi and his school (Benazzi, 1961), but the eastern ABBREVIATIONS IN THE FIGURES Mediterranean, and in particular Greece and USED the Greek "terra in- islands, are effectively ad adenodactyl mf muscular fibres cognita" as far as their triclad fauna is concern- af atrial fold mr muscular ridge ed. at atrium mz muscular zone There are only two species of the subgenus be bursa copulatrix nz nuclear zone known from Dugesia Greece, viz. Dugesia sagitta bs bursal canal ov oviduct atrium (Schmidt, 1861), from Corfu and Cephalonia, ca common pb penis bulb dp diaphragm pf penial fold and Dugesia cretica (Meixner, 1928) from Crete. duct ed ejaculatory pg penial glands Schmidt did not a sufficient Unfortunately, give fd fold pp penis papilla of D. and morphological description shell sagitta, go gonopore sg glands this with seminal vesicle subsequently species was synonymized lu lumen sv male atrium vd deferens D. gonocephala by Komarek (1925). There have ma vas also been reports on the karyology of two lucida sketches. Drawings were made from camera On from Dugesia species Corfu one of (Ball, 1979), each the bar 200 figure scale represents /tm. the species belonging to the subgenus Schmidtea, and the other to the subgenus Dugesia. Further- more, there are some karyological data known MATERIALS AND METHODS from D. cretica (see Dahm, 1958; Benazzi & For sectioned Benazzi-Lentati, 1976). Apart from these data, morphological study specimens were serially at 8 intervals, stained by Mallory-Heidenhain, from the Greek /im the Dugesia species region are Phosphotungstic acid haematoxylin, Masson's trichome or unknown. and mounted DePeX. each first Azan, in On slide the sec- For all these the reasons was tion is the when the label is the opportunity on upper left corner slide to Downloaded from Brill.com10/07/2021 01:01:34PM via free access - 1984 103 BIJDRAGEN TOT DE DIERKUNDE, 54 (1) and sections the ribbons right. For sagittal transverse were inner in the extra longitudinal layer outer mus- arranged vertically, and for frontal sections the ribbons cle zone. The bulk of the material has were arranged horizontally. The paired ovaries are ventrally located just been deposited in the Zoölogisch Museum of the Universi- Additional material loaned behind the brain. the oviducts arise ty of Amsterdam (ZMA). was Typically by the Museum für Naturkunde der Humboldt- from the dorsal side of the ovaries from where Berlin Universitàt, (ZMB). caudad the of the they run ventrally to level dorsad copulatory apparatus. Here they turn and into the of the open separately vaginal area SYSTEMATIC SECTION bursal canal just above the shell glands. The abundant vitellaria are distributed both dorsally All the species described in this belong to paper and ventrally throughout the body length, the D. and the gonocephala thus are closely group first follicles occurring just in front of the related. This that have several implies they ovaries. features in These morphological common. and dor- The follicular testes are numerous features best reference to are expressed by sal, extending throughout the body length from itself. In this Dugesia gonocephala way un- the a position just beside ovaries. avoided the necessary repetition is in species The bursa copulatrix is lined with a high descriptions, and in the latter the individual glandular epithelium. Stalked spermatophores variations on the morphological "groundplan" often are to be seen in the bursa. The will be given. To facilitate comparison a musculature of the bursal canal is of the re- character table is table I. provided as versed type, with inner, subepithelial, longitudinal muscles overlain with circular fibres. The epithelium of the bursal canal Dugesia gonocephala (Dugès, 1830) may 1) be either infranucleate or nucleate. Typically, (Fig. there of but not always, is an extra outer layer Planaria 1830: 83. gonocephala Dugès, fibres in the longitudinal vaginal area forming Dugesia gonocephala; Girard, 1850: 265. an ectal reinforcement of the bursal canal. This Euplanaria gonocephala; Hesse, 1897: 549.