Two monocelid species with simplex copulatory bulbs and post-pharyngeal ovaries have been found in E. Australia. One of them presents a combination of characters not found in any of the known genera of the Monocelididae, and the new genus Acanthopseudomonocelis is proposed for it. The new genus is characterized by the presence of four stylet-bearing accessory organs and by an internal vagina; it is related to Pseudomonocelis. The other species, Pseudomonocelis schockaerti n. sp., is characterized by a complex bursa-vagina system, and by a highly muscular penial organ and male antrum. It is closely related to P. pardii Schockaert & Martens, 1987, from Somaliland. Two possibly additional species of the genus Pseudomonocelis , not found in a mature stage, are mentioned. The new findings considerably enlarge the known distribution of the genus Pseudomonocelis.
Arnold Ross and William A. Newman
The coral-eating barnacle Hoekia monticulariae (Gray, 1831), the only internal parasite among the Thoracica described to this day, is characterized by an irregularly-shaped shell nestled cryptically between the polyps of the hermatypic coral Hydnophora Fischer, 1807, which occurs throughout most of the Indo-West Pacific. Because of its protean form, cirripedologists have failed to appreciate the diversity of taxa related to Hoekia, a presumed monotypic genus. We describe seven new species divided between Hoekia and three new genera, Eohoekia, Parahoekia, and Ahoekia for which the Tribe Hoekiini is proposed. As in other pyrgomatids, calcareous overgrowth by the coral is inhibited around the edge of the wall and aperture. But in Hoekiini a pseudopolyp, upon which the barnacle feeds with modified trophi, covers the wall and aperture. Furthermore, rather than articulating with a calcareous basis, the wall is suspended in coral tissue. Its hypertrophied lateral margin ( = basal margin), in contact with the host’s tissue, is the site where metabolic activities are inferred to take place. In Hoekia and Ahoekia, the wall develops simple or connecting tubes that lead to openings in the margin, which serve as circulatory pathways. A hypertrophied margin and elaborated circulatory system suggests that the Hoekiini may not be wholly dependent on feeding directly on host tissue and/or coelenteronic material, but may also be absorptive parasites. Although other pyrgomatids, in the tribes Pyrgopsellini nov. and Pyrgomatini nov., exercise some control over their hosts by an apertural frill and through discontinuities between the shell and basis, they are still planktotrophic.
Editors Bijdragen tot de Dierkunde
Antonio C. Marques
Eudendrium pocaruquarum , a new species of athecate hydroid referable to the family Eudendriidae, is described from the state of São Paulo, Brazil. The species is very similar to the widespread Eudendrium ramosum (Linnaeus, 1758), differing from it in the smaller size of the large microbasic euryteles. Longstanding problems in the systematics of eudendriid hydroids are noted, and the inadequacies of many early descriptions of species are discussed. The nematocysts provide a supplementary character for discrimination of species of Eudendrium, although information on the cnidome appears to have been sometimes misinterpreted in literature.
Jan H. Stock and Thomas M. Iliffe
Four new species of Melitidae (Amphipoda)are described from anchihaline limestone caves in New Caledonia. Three species are classified with Josephosella Ruffo, 1985 (J. microps n. sp., J. debilis n. sp., and J. proiecta n. sp.) and a new genus, Caledopisa, is erected for the fourth species, C. levis n. sp. The new genus is related to Victoriopisa Karaman & Barnard, 1979.
J.W. Arntzen and M. García-París
Allozyme variation in 31 to 50 presumptive loci of 12 populations of European midwife toads of the genus Alytes show appreciable genetic divergences (D Nei from 0.29 to 0.72) among four groups. These groups correspond to A. cisternasii Boscá, 1879, A. obstetricans (Laurenti, 1768), A. muletensis (Sanchiz & Adrover, 1979), and a new species from the Betic mountains described here as A. dickhilleni n. sp. Smaller divergences among geographic groups of populations of A. obstetricans (up to D Nei = 0.17) support the existence of three geographic units in Europe corresponding to the previously recognized subspecies A. o. obstetricans and A. o. boscai Lataste, 1879, plus a third one described here under the designation of A. o. almogavarii n. ssp. The analysis of morphological variation among taxa using principal component and discriminant analysis shows a remarkable similarity between A. dickhilleni and A. obstetricans; these are cryptic species. A phylogenetic analysis of allozyme data using A. cisternasii as the outgroup supports a sister taxon relationship between A. muletensis and A. dickhilleni, with A. obstetricans the sister taxon to this clade. The historical biogeography of the genus is discussed.
Carlos Eduardo Falavigna da Rocha
Neocyclops (Protoneocyclops) ferrarii sp. n. is described from Candy’s Pond, Twin Cays, Belize. It is morphologically closest to N. (P.) wellsi Petkovski, 1986 from Mozambique and N. (P.) herbsti Petkovski, 1986 from the Red Sea.
Amparo Martí and Santiago Villora-Moren
A new species of Gammarella Bate, 1857 is described from shallow water, inhabiting the interstitial system in soft bottoms of the Chafarinas Archipelago (western Mediterranean,N. Africa). The relationships of Gammarella with the genera Nuuanu and Cottesloe are briefly discussed. Numerical taxonomic methods are utilized to differentiate between the morphologically related species and the intermediate species. In a table the principal differentiating characters of Gammarella species are presented. Gammarella garciai n. sp. is characterized by its intermediate position between Gammarella, Nuuanu and Cottesloe, showing an intergradation of characters. Gammarella garciai n. sp. and G. merringannee show ecologically intermediate characters between the larger species, probably nestling, with preference for lightless environments, and the smaller species. The group of smaller species, with eyes poorly developedor absent, show interstitial preferences. A map of the world distribution and a key to the 11 known Gammarella species are presented.
Sebastián Sanz and Dirk Platvoet
On several occasions, shrimps belonging to a new species of the genus Typhlatya were collected in a cave in the province of Castellón, Spain. This is the first record of the genus in the Iberian Peninsula. The species is described and the validity, distribution, and zoogeography of the genus, as well as the status of the genus Spelaeocaris, are discussed. Former models for the evolution of the genus Typhlatya and its genus group are reviewed, as well as the system of inner classification of the Atyidae and its biogeographical meaning. For the age and evolution of the genus we developed a new model based on vicariance principles that involves further evolution of each species after the disruption of the ancestral range. This allows new estimations for the age of the genus. Accordingly, we suppose that other proposals, such as recent dispersal through the sea, should be disregarded for this genus. The evolutionary development of this species is discussed in the context of the geological history of the area and the world distribution of the genus, the genus group, and the family.
Fred. N. Poeser
A new species of the genus Poecilia Bloch & Schneider, 1801 is recorded from El Salvador. Morphological and meristic data of P. marcellinoi n. sp. and of the sympatric P. salvatoris Regan, 1907 are analysed. Intra- and interspecific variation are compared and correlated with environmental and interspecific influences. A high degree of character displacement is observed in populations from stable freshwater habitats. In habitats with presumed marine influences, this character displacement is counteracted by ecological stress. Based on the evidence presented, subspecific separation of observed ecotypes from literature is rejected.