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Rony Huys

A new family Cristacoxidae is proposed to accommodate the monotypic genera Cristacoxa gen. nov., Noodtorthopsyllus Lang (ex Canthocamptidae) and Cubanocleta Petkovski (ex Laophontidae). Cristacoxa petkovskii gen. et spec. nov. is described on the basis of a single male collected from coralline sand of Bonaire, West Indies. N. psammophilus Noodt and C. noodti Petkovski are redescribed and refigured on the basis of new material from the Galápagos (Isla Santa Cruz), the West Indian Islands (Curaçao, Klein Curaçao, Bonaire) and the Canary Islands (El Hierro, Tenerife). The new family is characterised by the presence of an outer spinous process on the first antennular segment, the absence of the antennary exopod, the uniramous mandibular palp, the presence of conspicuous cristae on the precoxa and coxa of leg 1 and the elongation of the apical exopodal spines of P2 to P4. The Cristacoxidae are unique in having an equal number of setae/spines onthe P5 in both sexes. Examination of the ontogeny of this leg in males and females of Orthopsyllus spec. gives strong evidence that the cristacoxid P5 has undergone neotenous evolution. Males of Cristacoxidae are readily recognisable by their extremely long spermatophores. The new family is allocated to the superfamily Laophontoidea T. Scott, together with the Laophontidae T. Scott, the Laophontopsidae Huys & Willems, the Orthopsyllidae Huys and the Adenopleurellidae Huys. A phylogenetic analysis of the relationships within the superfamily is presented, and as a result Por’s (1986) concept of the Laophontoidea is refuted. Instead, it is concluded that the superfamily can be defined on the basis of the following apomorphies: (1) antennules with outer spinous process on segment 2; (2) antenna with allobasis bearing 1 seta; (3) antennary exopod quadrisetose; (4) P1 exopod without inner seta on exp-2 and 4 setae/spines on exp-3; (5) P1 endopod 2-segmented with elongated enp-1 and 2 elements on enp-2; (6) P2—P4 with 2-segmented endopods; exp-1 without inner seta; (7) sexual dimorphism of P3 endopod; (8) P6 bisetose with one member fused to somite. There is no close relationship neither with the Normanellidae Lang, nor with the Ancorabolidae T. Scott. The Laophontidae are considered the first offshoot in the evolution of the Laophontoidea because of the retention of the 8-segmented antennule in both sexes and the ancestral seta formulae on P2–P4. The other families can be assigned to two clades: the Adenopleurellidaeand the Laophontopsidae-Cristacoxidae- Orthopsyllidae-grouping. The Laophontopsidae and the Cristacoxidae are sister groups because of the shared sexual dimorphism of the P3 endopod (advanced type), and the fusion of antennular segments distal to the geniculation in the male. Emphasis is placed on the postembryonic development in the Laophontoidea of the male P3 endopod and P6 and on their homologies in the female. A reconstruction of the hypothetical ancestor of the Laophontoideais presented.

Annie Zuiderwijk

Courtship display characteristics are described and compared for the newts Triturus cristatus and T. marmoratus and patterns of male competitive behaviour are recognized. In interpreting the data, the operational sex ratio has to be taken into account, which was highly biased towards males in both species, more in T. marmoratus than in T. cristatus.

When sexual active, males of cristatus had more encounters than males of marmoratus, whereas the latter spent more time residing mating places. The male’s display towards a female differed in time structure, variability and in behaviour characteristics. T. marmoratus display follows a fixed pattern; males succeeded better in restraining a female than males cristatus did. Courting males cristatus allowed other males to intrude. Malemale encounters were longer and playful in T. cristatus, more violent in T. marmoratus. Comparison with data from the literature indicates that courtship of T. marmoratus has more features in common with that of T. vittatus than it has with the courtship of T. cristatus.

It is suggested that in the course of evolution T. marmoratus adopted a strategy of Sexual Defense by means of territoriality and overt fighting, whereas T. cristatus in contrast adopted a strategy of Sexual Interference by female mimicry. Male display components that played a major role during the adaptation of competitive strategy are identified as the “whip” behaviour in T. marmoratus and the “rocking” behaviour in T. cristatus.

Hans-Uwe Dahms

The copepodite antennule development of representatives of 6 harpacticoid families is studied and discussed in detail and that of 8 genera of harpacticoids from 7 families is schematically illustrated. Twenty-seven genera out of 17 harpacticoid families are compared on the basis of own investigations and data from the literature. The origin of newly formed segments can be determined by seta numbers of segments, relative segment length, furrows indicating previous articulations and by the position of the segment which bears the proximal aesthetasc. There are 2 zones of segment formation, both located in the middle part of the first antenna. Normal segment formation takes place distally from the second, aesthetasc-bearing segment from C I to C II and proximally of it from C III to C IV. At least in some species sexual dimorphism of first antennae is present from C II onwards. Females practically show the adult antennular state at C V whereas males undergo important changes from C V to C VI with proximal addition of segments, and often with distal fusions and formation of a unique armature due to adaptations in clasping behaviour. There are specific formation patterns in certain taxonomic groups. E.g. Harpacticidae, Canthocamptidae, Canuellidae and Longipediidae deviate in antennule formation from the rest of Harpacticoida. A higher number of antennular setae of C I which in most of the cases are reduced in C II may be interpreted as indicating an ancestral multisegmented antennule for Harpacticoida.

Rony Huys

The new genus and species, Dicrotrichura tricincta, is described from deep mud (1220 m) in the Ligurian Sea (western Mediterranean). It is the first tantulocaridan not found to be attached to a crustacean host but free living in the sediment. It is assigned to the Deoterthridae on the basis of the absence of a rostrum, the abdominal segmentation and the characteristic cephalic pore pattern. It can be distinguished from all known tantulocaridans in the presence of peculiar, bi-articulated caudal setae and the difference in thoracopodal setation between leg 2 and legs 3–5. Some new structures located on the attachment disc are described for the first time. D. tricincta is the second tantulocaridan to be recorded from the Mediterranean.

Elias Sánchez

A new species of Pseudoniphargus has been discovered in Gran Canaria in a spring at an altitude of 710 m a.s.l.; it has an elongate peduncle of the male uropod 3. Moreover, P. fontinalis was found in the same island; this is the first record outside Tenerife from where it was described. The biogeographical implications of these records are studied.

Maarten Scheepmaker and Jan van Dalfsen

Genetic differentiation among G. fossarum Koch, 1835 from different stations in Germany, Switzerland, Belgium and northern France, and the closely related Belgian form G. caparti Pètre-Stroobants, 1980 was investigated by electrophoresis at 20 enzyme loci. Although morphologically variable, geographically distant populations of G. cf. fossarum were hitherto considered conspecific. In the present study, populations of G. cf. fossarum and G. caparti were examined with reference to G. pulex pulex as an estimate for genetic differentiation at the species level.

With G. p. pulex as a standard, genetic differentiation among geographically distant populations of G. cf. fossarum is occasionally observed at species level. The populations of G. caparti studied were shown to be genetically very similar to certain populations of G. fossarum. The taxonomic status of G. caparti and the genetically distinct forms of G. fossarum is discussed.

Hans-Georg Müller

The first contribution to the isopod family Joeropsidae from the Society Islands is given. All of the four species reported herein, Joeropsis gertrudae n. sp., J. minutus n. sp., J. polynesiensis n. sp., and J. salvati n. sp., are new to science. These species occur only at locations with more or less strong wave exposition. The affinities of polynesian Joeropsidae to the other members of Joeropsis are discussed.

Rony Huys and Kris A. Willems

The taxonomic concept of the subfamily Normanellinae Lang (Harpacticoida, Laophontidae)is revised. As a result anew family Laophontopsidaeis proposed to accommodate Laophontopsis Sars and two new genera Aculeopsis and Telodocus. It is concluded that the presumed boreo-mediterranean distribution pattern displayed by the type species L. lamellifera (Claus) is merely the result of erroneous identifications. The population of northwest Europe is assigned to a new species L. borealis and another new species L. monardi is proposed for Monard’s (1928) material from Banyuls-sur-Mer. L. secundus Sewell is placed in the new genus Telodocus. Aculeopsis gen. nov. embraces only A. longisetosa spec. nov. and constitutes the most primitive genus of the family. The Laophontopsidaeare placed within the superfamily Laophontoidea. The Normanellinae are provisionally upgraded to family level despite their diphyletic status because this narrows the diagnosis of the Laophontidae considerably. The genera are attributed to two clearly defined but non-related subfamilies, Normanellinae Lang (Normanella Brady) and Cletopsyllinae subfam. nov. (Cletopsyllus Willey, Pseudocletopsyllus Vervoort). The genus Pseudocleta Lang is relegated to incertae sedis within the Laophontoidae.

Thomas E. Bowman

Lovenula (Neolovenula) alluaudi is widespread on Lanzarote, where it occurred at 22 of the 105 stations. On Fuerteventura it was found at only 2 of the 53 stations, both in the extreme north-west part of the island. It was also found in a reservoir on the south side of the small island of Alegranza. Samples collected at several hundred stations in the other Canary Islands failed to yield a single calanoid, supporting the belief that the eastern islands are fragments of the African continent that drifted to deeper waters.

Neue marine Cyclopoida Gnathostoma (Crustacea, Copepoda) von Puerto Rico

Amsterdam Expeditions to the West Indian Islands, Report 57

Hans-Volkmar Herbst

Im flachen Litoral der Küste von Puerto Rico (Westindische Inseln) wurden im Riff von Cayo Enrique in Kolonien der Koralle Ricordea florida Duch. & Mich. wenige Cyclopoida Gnathostoma gesammelt, die zu den Pterinopsyllinae und Euryteinae gehören. Es handelt sich um die folgenden Arten: Pterinopsyllus insularis n. sp., Euryte grata n. sp. und Ancheuryte notabilis n. g., n. sp.