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Fábio Lang da Silveira and André Carrara Morandini

Nausithoe aurea, a new species of scyphozoan Coronatae, is described from São Paulo State, Brazil. The solitary scyphistomae, with some zooxanthellae, strobilated producing planuloids and medusae; this represents an intermediate life cycle between that of metagenetic Nausithoidae and the submarine cave-dwelling, reduced medusa stage of Nausithoe planulophora (Werner, 1971). The periderm tube of the scyphistomae has 16 internal cusps in all whorls. The medusae present yellow pigment spots in most of their lappets. The early embryonic development is briefly described. Planuloid formation is hypothesized as explanation for polyp-stage philopatry.

Vincent Nijman

The colobine monkey Presbytis comata is confined to the rain forests of West and Central Java, Indonesia. In order to determine its distribution, a review of the literature, evidence from the study of museum specimens, and the results of recent surveys are presented. Recent surveys in the central parts of the island indicate that P. comata is still present on four volcanic mountain complexes, viz. Mt. Sawal, Mt. Slamet, Mts. Dieng, and Mt. Lawu. The present paper gives the results of the surveys combined with a review of its distribution. Altitudinal and habitat preferences, and the conservation status of the species are discussed.

Pedro Martínez Arbizu

Parastenocaris hispanica n. sp. is described from hyporheic groundwaters in Spain. The phylogenetic position of the new species within the fontinalis-group Lang is discussed. As a result P. fontinalis meridionalis Rouch is elevated to species rank. The fontinalis-group is characterized by six autapomorphic characters.

Cristian R. Altaba

The allozyme data base of Arntzen & García-París (1995) on midwife toads (Alytes, Discoglossidae) is reanalysed considering each locus as a discrete character. The phylogeny thus inferred differs from the one obtained with genetic distances in the position of A. dickhilleni from the Betic region – it appears that its sister species is the widespread A. obstetricans, not the Mallorcan endemic A. muletensis. This phylogenetic hypothesis agrees with the taxonomic treatment of the genus based on morphology. A testable biogeographic hypothesis is proposed to account for the diversification of midwife toads in Iberia and the Balearics. The postulated underlying geological changes were the spread of inland saline lakes that divided Iberia (16 mY B.P.), the emergence and break-up of the Betic orogen (14 mY), and the formation of the Betic Strait (8 mY). Dispersal over sea channels or during the Messinian Crisis (6 mY) are deemed unlikely on the basis of ecological and biogeographical data.

J.W. Arntzen and M. García-París

Three competing phylogenetic hypotheses for the genus Alytes (midwife toads) are evaluated. Based on quantitative coding of protein characters the most parsimonious solution shows a sister taxon relationship for Alytes dickhilleni and A. muletensis. The alternatives in which A. obstetricans has its sister group in either A. dickhilleni or A. muletensis lack support. Using calibrations derived from protein evolutionary rates, the vicariant events giving rise to A. obstetricans and the lineage leading to the A. muletensis and A. dickhilleni clade and the subsequent splitting between A. muletensis and A. dickhilleni cannot be placed much earlier than the Miocene-Pliocene boundary. Biogeographical scenarios invoking an earlier time of divergence should be rejected.

Johannes Dürbaum

Precopulatory mate guarding and mating behaviour of Tachidius discipes Giesbrecht, 1881, has been analysed using a video camera mounted on a microscope. Males preferably accompany fourth or fifth stage female copepodids during precopulatory mate guarding; only rarely are third copopodid stages guarded. Rare cases of males clasping juvenile males are also known. Males are active during mate guarding and constantly change the site of attachment of their antennules. This behaviour may ensure continued association of the adult male with the juvenile copepodid when the latter moults during the mate guarding phase.

M. Yacoubi-Khebiz, M. Boulanouar and N. Coineau

The interstitial stygobiotic isopods of the genus Microcharon (Crustacea) are diversified in Morocco. A new species, M. ourikensis, is described. The new species shows some original characters for this genus: large size, strong elongation in the first male pleopod exopodal inner lobe, 5-dentate mandibular pars incisiva, and 5 spines on the last mandibular palp segment. The species is a member of the Ibero-Maghrebin messoulii group. It is an endemic representative of the Ourika valley groundwater in the Moroccan High Atlas. It derives from a littoral marine ancestor which could have colonized the continental subterranean water during Turonian or Senonian Tethyan regressions.

Arthur G. Humes

Anchimolgus gratus n. sp., associated with the fungiid coral Lithactinia novaehiberniae Lesson, 1831 in New Caledonia, is distinguished from its congeners (except A. pandus Humes, 1978) by the formula III,I,5 on the third segment of the exopod of leg 4. The new species differs from A. pandus which is much smaller and in which the female genital double-somite is as long as wide.

Alexandr P. Rasnitsyn

Phylogenetic hypotheses are designed and tested (usually in implicit form) on the basis of a set of presumptions, that is, of statements describing a certain order of things in nature. These statements are to be accepted as such, no matter whatever evidence for them exists, but only in the absence of reasonably sound evidence pleading against them. A set of the most current phylogenetic presumptions is discussed, and a factual example of a practical realization of the approach is presented.

María C. Daponte, Roberto J. Castro and Graciela B. Esnal

Until 1973, when Van Soest revised Thalia Blumenbach, 1798, this genus comprised only two species: Thalia democratica (Forsskål, 1775) and Thalia longicauda (Quoy & Gaimard, 1824). The former showed great variability, which led Van Soest to distinguish five species: T. democratica, T. orientalis, T. rhomboides, T. cicar, and T. sibogae. Some authors have ignored this revision considering the observed differences of infraspecific level. In the present work new material is studied analysing variables not previously considered, such as the development of blastogenic stolons in the solitary zooids and the location of the tunnel opening through which the bud blocks are liberated. These characters previously permitted a separation of closely related species in the genus Ihlea. The results show that stolon features, even though they permit a separation of solitary zooids of Thalia longicauda, do not discriminate all species of the “T. democratica group” since they are only useful in distinguishing T. democratica from T. sibogae. Other variables, mainly qualitative, do permit differentiation. The sympatric distribution of these taxa supports Van Soest’s hypothesis as well.