Larval development of a gobiid fish,Odontohutis obscura obscura in comparison with that ofO. o. interrupta and ofO. platycephala

Larval development ofOdontobutis obscura obscura, reared withArtemia sp. andLimnodrilus sp. for about two months, was observed in a room maintained at 20±0.5°C. The development was classified into nine nominal stages, and was compared with that ofO. o. interrupta and ofO. platycephala. The size and shape of the eggs and the development of this species are similar to those ofO. o. interrupta andO. platycephala. From the juvenile stage,O. obscura is distinguishable fromO. platycephala by the appearance of dark bands on the body located in the same position as in adults.O. o. interrupta is also distinguished fromO. o. obscura in the juvenile stage by the presence of melanophores on the dorsal and ventral sides of the caudal peduncle. The anal fin fold ofO. obscura is higher than the dorsal fin fold, but the two folds are equal in height inO. platycephala. O. obscura has a well-developed air bladder and swims high in the water at the feeding stage.O. platycephala has a poorly developed air bladder and swims on the bottom. Xanthophores are observed at an earlier stage and more strongly developed inO. obscura than inO. platycephala. Growth rate is faster inO. obscura than inO. platycephala. O. obscura spawns at a smaller body size thanO. platycephala. InO. o. obscura, the arrangement of cephalic pit organs is completed at 14 mm SL. InO. o. interrupta, this arrangement is completed at the same time or a little later than inO. o. obscura. The infraorbital and verticalantorbital pit lines ofO. platycephala, which are separated in the adults, are connected until the juveniles measure about 30 mm SL. These pit lines are connected even in the adults ofO. o. obscura andinterrupta. InO. platycephala, the sensory canals are first formed behind the eyes, then dorso-anterior to the eyes, then at the posterior edge of the preopercles and finally anterior to the eyes. Postocular canals begin to form in individuals more than 20 mm SL. All individuals ofO. o. interrupta more than 70 mm SL have postocular canals.O. o. obscura has no sensory canals throughout life. The differences in growth rate, body size at spawning, and the time of completion of the cephalic lateral line system suggest paedomorphosis in the three taxa studied here.     

Prolagus italicus n. sp. (Ochotonidae, Lagomorpha), a new Pliocene species of peninsular Italy

Prolagus italicus n. sp., a new endemic Pliocene species of peninsular Italy, is described here, adding new details to the knowledge of this widespread and long-lasting ochotonid genus. Several dental morphodimensional characters suggest a close relationship between P. italicus and P. sorbinii (evaporitic and postevaporitic Messinian, central Italy). On the other hand, P. italicus shares with other Plio-Pleistocene Prolagus species of continental Europe a large size and some peculiar characters of dental occlusal surface. Actually, an evolutionary trend can be detected in Plio-Pleistocene species of the genus Prolagus. The value of P. italicus in biochronology is quite consistent, as this species seems to mark MN17 in central Italy. Moreover, some morphodimensional differences between P. italicus populations have been identified: this can help to infer relative chronological positions to the fossil sites in which P. italicus is present. Some morphological characters present in one of the two available P. italicus populations are apparently related to ecological more than to evolutionary factors: this may be a starting point for in-depth palaeoecological studies related to the genus Prolagus. The presence of P. italicus in the Italian peninsula may have prevented the entrance of other species of western European affinity.     

New discoveries on the giant hedgehog Deinogalerix from the Miocene of Gargano (Apulia,Italy)

During the Miocene, the Abruzzo/Apulia region (Italy), isolated from the continent, was the theatre of the evolution of a vertebrate ecosystem in insular context. During the Late Miocene, the protagonists of this ecosystem called “Mikrotia fauna” show a high endemic speciation level, presenting spectacular giant and dwarf species of mammals and birds. Deinogalerix is one of the most uncommon forms of this peculiar fauna. It is the largest Galericinae that ever lived. From Gargano (Apulia, Italy) deposits (also called “Terre Rosse”), Deinogalerix has been, since its discovery in the 1970s’, the subject of two publications in which various morphotypes were described. Its presence is also attested at Scontrone (Abruzzo, Italy). In 2005, the new Miocene fissure “Mikrotia 013” (M013) was found in the Gargano area at Cava Dell’Erba by a team of the Università degli studi di Torino. The study of the micromammals, and in particular the presence of an archaic form of Mikrotia, attests that M013 is the oldest fissure known to date. All the Deinogalerix remains come from the smallest morphotype ever found. The morphological features (other than size) allow us to describe the new species Deinogalerix masinii. It presents a large variability of dental and mandibular features expressed in mosaic patterns within the material: the robustness of the upper and lower P3 and P4, and the characteristic trigonid of m1 of the genus; the archaic morphology of the maxilla and the mandible; the abrading pattern of the teeth are unique for Deinogalerix. These new remains allow us to update the knowledge of Deinogalerix. The suit of characters testified that D. masinii nov. sp. is an archaic form on the evolutionary trend toward the most derived representatives of the genus. The affinities of Deinogalerix with the Parasorex group are confirmed, but the time of immigration in Gargano remains debated.     

Nouvelles espèces de dasycladales du crétacé inférieur de provence (S.E. France)

In the Lower Cretaceous of Provence Cylindroporella faronensis n. sp. and Cylindroporella massiliana n. sp. represent small size species with a limited number of branches. The former ranges from the Middle (or Lower p.p. ?) Berriasian to the Lower Valanginian, the latter is found in the Lower Hauterivian, but could appear earlier in other regions. Clypeina isabellae n. sp. is also a small size form with a fibrous, yellowish microstructure, close to Clypeina sulcata, it is restricted to the Middle (or Lower p.p. ?) and Upper Berriasian. Besides their biostratigraphic and palaeobiogeographic potential value this material from Provence is also interesting from an evolutionary point of view. At generic levels it shows distinctive patterns relatively to the “Cope law”.     

Patch size drives colonization by aquatic insects,with minor priority effects of a cohabitant

Patch size is one of the most important factors affecting the distribution and abundance of species, and recent research has shown that patch size is an important niche dimension affecting community structure in aquatic insects. Building on this result, we examined the impact of patch size in conjunction with presence of larval anurans on colonization by aquatic insects. Hyla chrysoscelis (Cope''s gray treefrog) larvae are abundant and early colonists in fishless lentic habitats, and these larvae can fill multiple ecological roles. By establishing larvae in mesocosms prior to colonization, we were able to assess whether H. chrysoscelis larvae have priority effects on aquatic insect assemblages. We conducted a series of three experiments in naturally colonized experimental landscapes to test whether (1) H. chrysoscelis larval density affects insect colonization, (2) variation in patch size affects insect colonization, and (3) the presence and larval density of H. chrysoscelis shift colonization of insects between patches of different size. Larval density independently had almost no effect on colonization, while patch size had species‐specific effects consistent with prior work. When larvae and patch size were tested in conjunction, patch size had numerous, often strong, species‐specific effects on colonization; larval density had effects largely limited to the assemblages of colonizing beetles and water bugs, with few effects on individual species. Higher larval densities in large mesocosms shifted some insect colonization to smaller patches, resulting in higher beta diversity among small patches in proximity to high density large mesocosms. This indicates establishing H. chrysoscelis larvae prior to insect colonization can likely create priority effects that slightly shape insect communities. Our results support the importance of patch size in studying species abundances and distributions and also indicate that colonization order plays an important role in determining the communities found within habitat patches.     

Studies on protozoan parasites of Australian fishes. Notes on coccidian parasites with description of three new species

In 1990 several species of the generaEimeria andGoussia were found during the examination of some marine and freshwater fishes in New South Wales for protozoan parasites. In freshwater hosts,Goussia carpelli (Léger & Stankovitch, 1921) was found inCarassius auratus from a fish farm andEimeria anguillae Léger & Hollande, 1922 inAnguilla australis from feral eels. A new species,G. piekarskii n. sp., is described from the small intestine of feralGambusia holbrooki. Spherical or subspherical oöcysts average 9.2 μm in diameter, the average size of sporocysts being 7.6 × 4.2 μm. From coastal marine fishes,Goussia thelohani labbé, 1896 was identified in the liver parenchyma ofAcanthopagrus australis andRhabdosargus sarda. G. cruciata (Thélohan, 1892) Labbé, 1896 was found in the liver parenchyma ofPseudocaranx dentex. Both species were found for the first time outside the European area and in completely different hosts.Eimeria sillaginis Molnár & Rohde, 1988 is redescribed from the intestine ofSillago ciliata, and includes a new structure on its sporocyst wall.E. nesowai n. sp. is described from the pyloric caeca and intestine ofGerres ovatus. Subspherical oöcysts average 12.9 μm in diameter, the average size of sporocysts being 7 × 4.2 μm.E. rohdei n. sp. was found to infect the pyloric caeca ofMonacanthus chinensis. The average sizes of oöcysts and sporocysts are 7.5 μm diameter and 5.1 × 3 μm, respectively.     

Ossicaulis lachnopus (Agaricales, Lyophyllaceae), a species similar to O. lignatilis, is verified by morphological and molecular methods

Identity of Ossicaulis lachnopus and O. lignatilis was studied using both classical and molecular methods. While O. lignatilis is a well-known species, O. lachnopus is almost unknown, having been resurrected to modern mycology by M. Contu in 2000. Based on collections from six European countries, both classical and molecular methods independently proved that the species really represent two separate entities. They form two well-supported clades that correlate to morphologically separable groups. The most important distinguishing characters are the size of spores, especially their length, and a pileus colour. O. lachnopus has small spores and a grey or beige-grey tinged pileus, whereas O. lignatilis has larger spores and a whitish to cream pileus, with a slight beige-greyish tinge at most. In this paper, we discuss taxonomy, ecology and distribution of both species and propose a preliminary key for their identification.     

Some observations on mating behaviour of several cranes in captivity

Responding to the actions of the mate and taking somewhat fixed patterns,Grus japonensis, G. vipio, G. antigone, Anthropoides paradisea andBalearica regulorum pairs are finally led to copulation by a sequence of mating behaviours. There are slight differences in pre-copulatory behaviour patterns between the species and the female's ‘wing-spreading’, being the soliciting and key posture for copulation, differs between the genera; The female's wings are spread wide inGrus, fairly wide inAnthropoides, and are almost folded inBalearica. Post-copulatory behaviours, however, have definite species-specific characters. They usually consist of ‘head-down’ (bowing) or ‘warping’, ‘arching’, etc. immediately following the dismounting of the male inGrus. But a pair ofBalearica first keep their heads high, or gaze at each other for a while, and then show remarkable ‘ruffle-bowing’. These characteristic post-copulatory behaviours are obviously correlated with the threat displays, evolved under agonistic situations, typical to each species.     

Diversity of Phytophthora Species from Declining Mediterranean Maquis Vegetation,including Two New Species,Phytophthora crassamura and P. ornamentata sp. nov.

The Mediterranean basin is recognized as a global biodiversity hotspot accounting for more than 25,000 plant species that represent almost 10% of the world’s vascular flora. In particular, the maquis vegetation on Mediterranean islands and archipelagos constitutes an important resource of the Mediterranean plant diversity due to its high rate of endemism. Since 2009, a severe and widespread dieback and mortality of Quercus ilex trees and several other plant species of the Mediterranean maquis has been observed in the National Park of La Maddalena archipelago (northeast Sardinia, Italy). Infected plants showed severe decline symptoms and a significant reduction of natural regeneration. First studies revealed the involvement of the highly invasive wide-host range pathogen Phytophthora cinnamomi and several fungal pathogens. Subsequent detailed research led to a better understanding of these epidemics showing that multiple Phytophthora spp. were involved, some of them unknown to science. In total, nine Phytophthora species were isolated from rhizosphere soil samples collected from around symptomatic trees and shrubs including Asparagus albus, Cistus sp., Juniperus phoenicea, J. oxycedrus, Pistacia lentiscus and Rhamnus alaternus. Based on morphological characters, growth-temperature relations and sequence analysis of the ITS and cox1 gene regions, the isolates were identified as Phytophthora asparagi, P. bilorbang, P. cinnamomi, P. cryptogea, P. gonapodyides, P. melonis, P. syringae and two new Clade 6 taxa which are here described as P. crassamura sp. nov. and P. ornamentata sp. nov. Pathogenicity tests supported their possible involvement in the severe decline that is currently threatening the Mediterranean maquis vegetation in the La Maddalena archipelago.     

New species of sub-fossil weevils (Coleoptera,Curculionidae) in Madagascar copal

Two new species of the subfamily Cossoninae are described from Madagascar copal. Pentarthrum inclusus sp. nov. is similar to P. alpinum Hustache, 1933 but differs in the smaller body size, almost straight rostrum, almost flat eyes, temples with smooth punctures, and the shorter 3rd antennomere. Cossonus shevnini sp. nov. is similar to C. suturalis Boheman, 1838, differing in the unicolorous body, uniformly punctured pronotum, and more convex eyes.     

Multiple oviposition and larval feeding strategies in Euphydryas maturna (Linné, 1758) (Nymphalidae) at two disjoint European sites

Globally, Euphydryas maturna is a polyphagous butterfly species. At our study sites in Italy and Germany however, the plant used for egg-laying was almost exclusively Fraxinus excelsior. Nevertheless, in Germany, two egg-batches were found on Ligustrum vulgare and one on Viburnum opulus. Females lay their egg-batches at low heights and mostly on small trees (but not <1 m). At the end of the flight season, small egg-batches are laid and we conclude that these are late batches laid by “old females”. Egg-batches and pre-diapause larval webs are often clustered on certain trees and even leaves. This was shown to be a result of female behaviour and not of habitat quality, since the trees chosen were different in subsequent years. Individual females may return for laying further egg-batches to the place of the first egg-deposition and other females follow, since the survival of pre-diapause larvae is higher when more larval webs are on one tree. A further possible advantage during hibernation is discussed. In Italy, post-hibernation larvae form two distinct cohorts: larvae feeding on herbaceous plants (Plantago major, P. minor, Veronica hederifolia), and larvae feeding on Fraxinus excelsior. Although the latter group starts feeding later and pupates later, it reaches the same pupation weight. At our German site, post-hibernation larvae were found almost exclusively on F. excelsior. In fact, we observed larvae searching for food on F. excelsior while the buds of this tree were still closed. We also found larvae searching for food in the herbal layer without finding suitable plants. In some areas, larvae have to wait for the buds of the ash tree to open. Our data suggest that conservation strategies for E. maturna must be site specific according to food plant use of pre- and post-hibernation larvae and habitat type.     

Speciation and paraphyly in western mediterranean hares (Lepus castroviejoi,L. europaeus,L. granatensis,andL. capensis) revealed by mitochondrial DNA phylogeny

Mitochondrial DNA (mtDNA) variation among specimens of the northwestern African hare (Lepus capensis schlumbergeri) and three European hares sampled in Spain (L. castroviejoi andL. granatensis, which are endemic to the Iberian Peninsula, andL. europaeus) was analyzed using seven restriction endonucleases. Fourteen haplotypes were found among the 34 animals examined. Restriction site maps were constructed and the phylogeny of the haplotypes was inferred. mtDNA ofL. capensis was the most divergent, which is consistent with its allopatric African distribution and with an African origin of European hares. We estimated that mtDNA in hares diverges at a rate of 1.5–1.8% per MY assuming that the European and African populations separated 5–6 MYBP. Maximum intraspecies nucleotide divergences were 1.3% inL. capensis, 2.7% inL. castroviejoi, and 2.3% inL. granatensis but 13.0% inL. europaeus. The latter species contained two main mtDNA lineages, one on the branch leading toL. castroviejoi and the other on that leading toL. granatensis. The separation of these two lineages from theL. castroviejoi orL. granatensis lineages appears to be much older than the first paleontological record ofL. europaeus in the Iberian peninsula. This suggests that the apparent polyphyly ofL. europaeus is due not to secondary introgression, but to the retention of ancestral polymorphism inL. europaeus. The results suggest thatL. europaeus either has evolved as a very large population for a long time or has been fractionated. Such a pattern of persistence of very divergent lineages has also been reported in other species of highly mobile terrestrial mammals. As far as mtDNA is concerned,L. europaeus appears to be the common phylogenetic trunk which has diversified during dispersion over the European continent and from whichL. castroviejoi andL. granatensis speciated separately in southwest Europe.     

Biochemical research on oogenesis. The storage particles of the teleost fish Tinca tinca

Oocytes ofTinca tinca and other Teleosts accumulate small and large molecules of RNA in noncoordinate fashion. Previtellogenic oocytes synthesize far less 28 S and 18 S RNA than tRNA and 5 S RNA, so that the latter molecules make up 50 to 90% of total RNA in these cells. As inXenopus laevis, tRNA and 5 S RNA made in excess by small oocytes ofT. tinca are stored in two kinds of nucleoprotein particles, sedimenting at 7 S and 42 S. In this paper we describe the biochemical and physical properties of the storage particles ofT. tinca. The 7 S particles are made up of one 5 S RNA and one 32,000 M_r protein (c). The molecular weight of this protein is lower by 8,000 than itsX. laevis counterpart. In contrast, the 42 S particles have the same size and composition inT. tinca andX. laevis. The 42 S particles of both species are made up of four subunits, each of which contains three molecules of tRNA, one molecule of 5 S RNA, two molecules of a 50,000-M_r protein (a), and one molecule of a 40,000-M_r protein (b). We present evidence showing that in the 42 S particles protein a is associated with tRNA, whereas protein b is associated with 5 S RNA, and suggesting that protein c is a cleavage product of protein b.     

Genetic and phenotypic variation for flight ability in the cactophilicDrosophila species,D. aldrichi andD. buzzatii

The flight ability ofDrosophila aldrichi (Patterson & Crow) andD. buzzatii (Patterson & Wheeler) using tethered flights, was measured with respect to age-related changes, genetic variation and adult body size variation induced by rearing at different larval densities.Drosophila buzzatii flew for much longer thanD. aldrichi, especially females, but age-related changes in flight duration were significant only forD. aldrichi. Effects of body size on flight ability were significant inD. buzzatii, but not inD. aldrichi. InD. buzzatii, there was a significant genotype-environment interaction (larval density × line) for flight duration, with short and average flight duration isofemale lines showing longer flights, but a long flight duration line shorter flights as body size decreased (i.e., as larval density increased). Heritability estimates for flight duration were similar in the two species, but flight duration showed no significant genetic correlations with developmental time, body size or wing dimensions (except for one wing dimension inD. buzzatii). Although not significantly different between the species, heritabilities for life-history traits (adult size and developmental time) showed contrasting patterns — with higher heritability for body size (body weight and thorax length) inD. buzzatii, and higher for developmental time inD. aldrichi. In agreement with limited previous field evidence,D. buzzatii is better adapted for colonization than isD. aldrichi.     

Sexual dimorphism of craniological characters in Eurasian badgers, Meles spp. (Carnivora, Mustelidae)

An analysis of 30 craniological characters of Eurasian badgers (Meles spp.) revealed different levels of sexual size dimorphism (SSD) and geographic variation in the three different species. SSD is displayed mostly in the general size of the skull (condylobasal length, zygomatic width, width of rostrum, and cranial height) and mandible (height of the vertical mandibular ramus, total length of the mandible, and length between the angular process and infradentale), and in some dental characters (length of the upper molar M¹). The most stable size dimorphism is manifested in the size of the canines, which is pronounced in all studied samples. SSD is not apparent in the length of the auditory bulla, the postorbital width, the minimum palatal width, the length of the lower molar M₂, and the talonid length of the lower carnassial tooth M₁.In both the European badgers, Meles meles, and the Asian badgers, Meles leucurus, two geographic forms that differ in the degree of SSD have been found. The most pronounced SSD of cranial characters is found in the Transcaucasian form of Meles meles and the Far-Eastern form of Meles leucurus. In the large European form of Meles meles, SSD is less pronounced in both absolute and relative criteria than in the smaller Transcaucasian form. An analogous situation is observed in the larger Siberian and smaller Far-Eastern forms of Meles leucurus. In the Japanese badgers, Meles anakuma, a downsizing of the skull is accompanied by a decrease in SSD (except in canine size) in comparison to the continental species. The significant differences in the manifestation of SSD in the Eurasian badgers support an earlier hypothesis (Abramov, 2001. Proc. Zool. Inst. Russ. Acad. Sci. 288, 221-233; Abramov, 2002. Russ. J. Theriol. 1 (1), 57-60; Abramov, 2003. Small Carnivore Conserv. 29, 5-7) that Meles meles, Meles leucurus, and Meles anakuma are separate species. The differences in the level of SSD among and within these three species of badgers may be attributed not to differences in the diet or social structure, but to the history of speciation events and formation of intraspecific distribution ranges.     

New records of fish parasitic isopods of the gill-attaching genus Mothocya Costa,in Hope, 1851 from the Virgin Islands,Caribbean, with description of a new species

Two species of Mothocya Costa, in Hope, 1851 are reported from the Virgin Islands. Mothocya xenobranchia Bruce, 1986 was collected from St. John Island from the gills of the Atlantic needlefish, Strongylura marina, which is a new locality record and also confirms a previously uncertain host identity. Mothocya bertlucy sp. n. is described from St. Thomas, St John and Guana Islands, from the gills of the redlip blenny, Ophioblennius macclurei, the first record of a blenny as host for any Mothocya. The distinguishing characters of Mothocya bertlucy sp. n. include its small size (< 9 mm) and eyes, the slender pleotelson with a narrowly rounded caudomedial point, extended uropod peduncle and uropods which do not extend past the pleotelson posterior margin, and the narrow pleon which is only slightly overlapped by pereonite 7.     

Tabanidae (Diptera) of Amaz?nia XXI. Descriptions of Elephantotus gen. n. and E. tracuateuensis sp. n. (Diachlorini) from the Brazilian coast

Elephantotus, a new genus of Tabanidae from the Amazon coast, Brazil, is described based on a new species E. tracuateuensis. Five females were collected in Pará State, and a male in Maranhão State. Arguments are presented for separating the new genus from Dasybasis, as well as the possibility of its occurrence being related to the nesting sites of coastal birds. The new species is characterized by its large size (x = 2.15 cm, n = 5 females), glabrous eyes, reddish-brown tegument, light brown frontal callus not touching the edges of the eyes, extending up to the vertex that has traces of ocelli, basal plate of the antennal flagellum with obtuse angle, without a tooth or spine, wings hyaline, with brown basal cells, without appendix in the fork of vein R₄₊₅, and genital furca wide with extended flaps.     

Swarming Behavior, Sexual Dimorphism, and Female Reproductive Status in the Sex Role-Reversed Dance Fly Species Rhamphomyia marginata

Dance flies are predaceous insects which often form male mating swarms. In many species males prior to swarming catch an insect prey, which is presented to the female at mating. In Rhamphomyia marginata, females in contrast to males gather to swarm, while males carrying a prey visit swarms for mating. Here I describe the swarming and courtship behavior in R. marginata and provide data on sexual dimorphism and swarming female reproductive status. Females swarm in small clearings in the forests. There was no specific swarm-maker. The swarming period lasted for 2–3 h and peaked around sunset. Identical swarm sites were used each evening and for several years. The mean number of females in swarms (swarm sites with at least one female) was 9.9 ± 9.1 (range, 1–40; n = 107) in 1993 and 7.1 ± 7.0 (range, 1–35; n = 68) in 1994. No obvious competition between females in swarms was observed. The operational sex ratio in swarms was extremely female biased (all swarms, 0.04). Less than one-third of male visits to swarms resulted in mating and males were found more often in larger swarms. Nuptial prey consisted of male midges. Females seem to mate more than once. Swarming females had undeveloped eggs, whereas mated females in swarms had further developed eggs than unmated females. Amount of sperm in the spermatheca was correlated with egg size. Amount of sperm and egg size did not correlate with wet weight, wing length, or wing load, except for egg size and weight. The wing coloration pattern and shape in R. marginata females are unique among dance flies, being greatly enlarged (1.6 times larger than that of males) and bicolored (gray part, 60% of wing area). When females, instead of males, possess extravagant secondary sexual characters, it is predicted from sexual selection theory that females should compete for males and that males should be selective in their choice of partner. A sex-role reversal will evolve when assess to males limit female reproductive success. The dance fly species R. marginata, like Empis borealis, another dance fly species studied earlier and discussed here, seems to fit these predictions.     

Scanning electron microscopic observations on the head morphology of seven different leptocephali belonging to six eel families (Anguilliformes)

Scanning electron microscopy observation was carried out on head morphology, number and construction of teeth, nostril position and the presence of neuromasts of seven species of leptocephali from six families of the Anguilliformes. The number and form of the teeth vary within the different families, from 76 teeth inGnathophis sp. (Congridae) to 32 teeth inAnarchias yoshiae (Muraenidae). In most of the genera the number of teeth on upper and lower jaws is almost equal, except inGnathophis sp.,Anguilla anguilla andKaupichthys hyoproroides. The unusual size and form of the leptocephali's teeth led us to speculate on the feeding behaviour of these larvae. Tentatively we suggest that the tooth formation of the leptocephali may act as a filtering system, rather than as a predatory apparatus, as its vicious appearance might suggest. Given the largely passive nature of a filtering system, the larvae would be able to concentrate on their migration. Of all the investigated leptocephali, onlyNemichthys scolopaceus shows one olfactory opening on each side of the head, whilst all the other species show two openings. The data obtained from these investigations suggest that teeth form as well as form and position of the nostrils are characteristics of the genera, and possibly also of the species.