Preliminary survey of Cacajao melanocephalus melanocephalus in Southern Venezuela

We conducted a survey of Cacajao melanocephalus melanocephalusin southern Amazonas, Venezuela, to update information on their distribution and to select a site for a longitudinal study. We surveyed along the Rio Negro, Brazo Casiquiare, Rio Pasimoni, and Rio Baria and interviewed local people. We observed C. m. melanocephalusfour times along the Rio Pasimoni (N =2)and the Rio Baria (N =2).Group size ranged from 3 to 20 individuals. They ate immature seeds from heavily armored fruit of the chicletree (Manilkara bidentataor Manilkara zapota)and Mauritia flexuosa.Local people reported hunting primates, particularly C. m. melanocephalus,once per week. Mercury residue from illegal gold mining may be poisoning local ecosystems. Hunting pressures may have eliminated C. m. melanocephalusfrom much of its range in southern Amazonas. Urgent steps must be taken toward the conservation of C. m. melanocephalus irathis region.     

Southern expansion of the geographical distribution ofCacajao melanocephalus melanocephalus

Cacajao melanocephalus melanocephalus, a subspecies of black uakari, was thought to be restricted to southern Venezuela. Observations of two groups of them in Pico da Neblina National Park, Brazil, suggest that its distribution should be extended to the Brazilian territory.     

Arthropod Predation by a Specialist Seed Predator, the Golden-backed Uacari (Cacajao melanocephalus ouakary, Pitheciidae) in Brazilian Amazonia

Morphological adaptations related to food processing generally reflect those elements of the diet that represent the greatest biomechanical challenge or that numerically dominate the diet. However, in periods of the annual cycle when the availability of such foods is low, items to which a species has low apparent morphological adaptation may be included in the diet. Here we test the responses of a diet-specialist primate to limitations in the supply of the resource it is specialized to exploit. Uacaris are primarily predators of immature seeds, in seasonally flooded forests in Amazonian Brazil, and have dental specializations to open hard-shelled fruits. We investigated the importance of arthropods in the diet of golden-backed uacaris (Cacajao melanocephalus ouakary), examining their seasonal importance in the uacari diet, and the ways C. m. ouakary used to access them. Using scan and ad libitum sampling of feeding and phenology from botanical study plots to assess fruit availability, we conducted an 18-mo study in Jaú National Park, Amazonas State, Brazil. We recorded arthropod predation 298 times, with Cacajao melanocephalus ouakary feeding on 26 invertebrate taxa in ≥11 families and 9 different orders. Uacaris extracted wood-boring beetles dentally from rotting wood and smaller larvae from twigs, stems, and petioles, but this food class did not predominate. This food class (encapsulated foods) constituted 23.4 % of the arthropod records. The majority of arthropod food items were either manually removed from substrates (ants, beetle larvae, caterpillars, fulgorid bugs, grasshoppers, mayflies, spiders, termites, wasps, and a whip-scorpion) or plucked from the air (volant Lepidoptera). Uacaris appeared to avoid toxic caterpillars. Insectivory was most frequent when fruit and seeds were least available. Arthropods seem to be seasonally important to this primate, supplementing or making up for shortfalls in the hard fruits and immature seeds for which uacaris have highly developed dental, and possibly intestinal, adaptations.     

Modeling the Geographical Distribution and Fundamental Niches of <Emphasis Type="Italic">Cacajao</Emphasis> spp. and <Emphasis Type="Italic">Chiropotes israelita</Emphasis> in Northwestern Amazonia via a Maximum Entropy Algorithm

We modeled the geographical distribution of 4 pithecine primate species: brown-backed bearded sakis (Chiropotes israelita) and 3 black uakaris (Cacajao melanocephalus, C. hosomi, and C. ayresi) that inhabit remote regions of western Amazonas, Brazil. We applied a maximum entropy algorithm modeling program (MAXENT) to field data Boubli collected from 1991 to 2007. We used 23 environmental coverage variables to model the distribution of the primates. The layers were related to precipitation, temperature, topography, and ecological bioregions or Ecoregions. The predicted distribution for Cacajao hosomi was strongly associated with the Negro-Branco Moist Forest and Guianan Highlands Moist Forests Ecoregions, and the Worldclim variables Bio3 (isothermality), Bio4 (temperature seasonality) and Bio17 (precipitation of the driest quarter). Cacajao melanocephalus was strongly associated with Japurá/ Solimões-Negro Moist Forests, Caquetá Moist Forests, Purús Várzea Flooded Forests, Rio Negro Campinaranas, and Cordillera Oriental Montane Forests, Ecoregions. Cacajao ayresi was strongly associated with Negro-Branco Moist Forest and Rio Negro Campinarana Ecoregions as well as Worldclim Bio3 (isothermality). Chiropotes israelita was also strongly associated with Worldclim Bio3 (isothermality) followed by the Negro Branco Moist Forests and Guianan Piedmont and Lowland Moist Forests Ecoregion, and to the Guianan Highland moist forests. These results show a great overlap between the bearded saki and 2 black uakaris, Cacajao hosomi and C. ayresi. Given that one cannot attribute the separation between the species in the Rio Negro-Rio Branco interfluvium to the existence of geographical barriers such as rivers, we suggest that the present geographical boundaries and thus coexistence of the 3 pithecines north of the Rio Negro is maintained by competitive exclusion or stochastic events. Until more surveys are conducted, the present geographical distributions of the pithecines and the mechanism maintaining their boundaries in the Rio Negro-Rio Branco interfluvium will remain uncertain. One important contribution of our model is to identify areas of higher probability of occurrence that might be helpful in guiding future survey expeditions and choices of areas for future conservation of pithecines.     

Propagation of the loud “tchó” call of golden-backed uakaris, Cacajao melanocephalus, in the black-swamp forests of the upper Amazon

Arboreal primates use loud vocalisations to transmit information in densely vegetated habitats. These vocalisations are likely to show adaptations to increase their propagation and to transmit information. Golden-backed uakaris, Cacajao melanocephalus, emit a loud vocalization termed the “tchó” call, which seems to function as a contact call and encodes information on the individual signaler and behavioural context. Because the call is often used for communication over relatively large distances, we were interested in its propagation in the wild. The aim of the present study was to investigate the degradation patterns of the tchó call in the flooded igapó forest. We examined via playback experiments how the acoustic parameters of this call changed with increasing distance from the playback speaker. We broadcast 12 tchó calls and rerecorded them along a transect at distances of 10, 20, 40, 80 and 160?m from the speaker in two igapó forest patches in Jaú National Park, Amazonas, Brazil. At 160?m from the speaker, the tchó call degraded in both patches and was barely recordable. Up to a distance of 80?m, the bandwidth and number of harmonics in the call decreased with increasing distance, while the lowest frequency increased. The highest frequency (HF) did not gradually decrease with increasing distance. However, when we compared the HF at distances of 10 and 80?m, we could see a clear decrease in this parameter. Call duration increased compared with the broadcast signal up to 40?m because of reverberation, but decreased at 80?m as the weaker echoes of the call attenuated. These changes may reveal information about the signaler’s distance during signal transmission. The frequency of maximum energy (FME) of the tchó call decreased significantly when comparing recordings made at 10 and 80?m. Nevertheless, it did not show a consistent and gradual decrease with increasing rerecording distance (at least up to 80?m). FME remained relatively stable (±50?Hz on average, at least up to 80?m) when compared to the other call parameters, suggesting that the tchó call may be adapted to transmit information with some efficiency throughout the igapó forest.     

Seasonal aspects of life cycles in Calathus melanocephalus and C. micropterus (Coleoptera, Carabidae) in the northern taiga

The seasonal dynamics of the activity and the demographic structure of Calathus melanocephalus and C. micropterus populations were studied in the northern taiga of Arkhangelsk Province. The period of adult activity lasts from early June to mid-or late September with the maximum surface activity observed in the middle of summer. In C. melanocephalus, mature individuals are recorded from early June to early September, and in C. micropterus, during the entire season. The data on seasonal changes of the demographic structure of the population demonstrate that in the northern taiga, these species probably possess a biennial life cycle with summer reproduction. The geographical variability of the demographic structure of populations and of life cycles of two species of the genus Calathus was demonstrated. Northwards from the south, the period of activity decreases and the period of reproduction increases and shifts from autumn to the middle of summer. A hypothesis was formulated, according to which in the species studied the annual life cycle in the central part of the range is replaced by the biennial cycle in the north.     

A new breeding population of Mediterranean Gulls Larus melanocephalus in the species' main wintering area maintains independent spatial dynamics

We studied a newly established breeding population of the range‐expanding Mediterranean Gull Larus melanocephalus in eastern Spain, situated in close proximity to the species' main wintering area. By investigating the origin, population composition and wintering area of the new breeders, we found that recruitment from locally wintering birds was unlikely and that the emerging colonies were probably attracting birds from populations wintering 700–1200 km away in Portugal and southern Spain. Our findings reveal that expanding populations may follow their own dynamics, independently of other populations of the same species, and may consist of different individuals altogether.     

Potential benefits of iridoid glycoside sequestration in Longitarsus melanocephalus (Coleoptera,Chrysomelidae)

Whenever potentially noxious plant compounds are taken up and recycled by herbivorous insects, a protective function of these sequestered compounds is assumed. The flea beetle Longitarsus melanocephalus sequesters iridoid glycosides from its host plant up to a concentration of 2% DW, yet so far it remained unknown whether the insects gain protection from natural enemies by sequestering plant compounds at these comparatively low concentrations. Here we tested whether iridoid glycosides might deter or inhibit various soil and litter-dwelling potential enemies and pathogens. In choice experiments presenting L. melanocephalus pupae together with Tribolium castaneum pupae, the predator Lithobius forficatus was deterred by the iridoid glycoside containing pupae, while Forficula auricularia as well as the nematode Heterorhabditis bacteriophora were not deterred. L. forficatus also avoided artificial baits doted with 2% iridoid glycosides while F. auricularia showed no aversion to iridoid glycosides at these concentrations and H. bacteriophora did not suffer any toxic effect. Of the pathogens tested, the entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae were not inhibited in their growth by iridoid glycosides ranging up to 2%. However, an inhibitory effect could be observed against the entomopathogenic bacterium Bacillus thuringiensis, even at the relatively small concentrations that are common in L. melanocephalus. The antibacterial effect might thus be another important selective value of iridoid glycoside sequestration in this species.     

Spatial patterns of host exploitation in a larval parasitoid of the predatory dusky large blue Maculinea nausithous

The foraging behaviour of the parasitoid wasp Neotypus melanocephalus and factors affecting parasitism at the population level were studied. This specialised parasitoid attacks caterpillars of the butterfly Maculinea nausithous, which sequentially feed on the plant Sanguisorba officinalis and specific red Myrmica ants. Among M. nausithous populations, there is considerable variation in caterpillar densities. At low M. nausithous densities, foraging might be time consuming for N. melanocephalus. High host densities may not always be advantageous to foraging parasitoids due to the caterpillars’ frequent overexploitation of ant resources and subsequent density-dependent mortality. In order to disperse progeny, we hypothesised that N. melanocephalus should search in a non-random way at the level of the micro-habitat, i.e., single flower heads of S. officinalis. Our analysis of 32 natural populations in the Upper Rhine valley in Germany did not show a density-dependent relationship between M. nausithous caterpillars and parasitism. Furthermore, habitat parameters like patch size and density of the host's food plant did not affect the parasitism rate. Foraging N. melanocephalus females preferred to search on large flower heads. They probed host-occupied flower heads only, visiting non-host-exploited flower heads only briefly. Time spent on a flower head was independent of the number of caterpillars per flower head. This study indicates that N. melanocephalus increases its foraging efficiency by preferring large flower heads that were previously shown to contain more host caterpillars than small flower heads. Furthermore, oviposition increases the likelihood of continuing to search on a flower head, which is an adaptive strategy for parasitoids foraging for aggregated hosts. However, many host-occupied flower heads were not probed by N. melanocephalus. We discuss the possibility that temporal host refuges of M. nausithous caterpillars might contribute to heterogeneity of parasitism, and why spreading offspring might constitute a suitable strategy for a parasitoid of an ant-parasitic butterfly.     

Fecundity in relation to wing-morph of three closely related species of the melanocephalus group of the genus Calathus (Coleoptera: Carabidae)

Summary In two successive years the fecundity of the carabid beetles Calathus (Neocalathus) cinctus, C. (N.) melanocephalus and C. (N.) mollis was studied in relation to wing-morph and temperature. Differences were found between the three species in both egg production and timing and length of the oviposition period. In all species the fecundity of laboratory bred beetles was significantly higher than that of females collected in the field. Long-winged females of both cinctus and melanocephalus had significantly higher egg production than short-winged females, and they also tended to produce eggs over a longer period. In mollis only the fecundity of the long-winged morph was established. The observed lower relative fitness of the short-winged morph in both cinctus and melanocephalus contradicts the supposed increase of the frequency of this morph in ageing, more or less isolated, populations of these species. The loss of long-winged genotypes, resulting from flight activities, is considered the most plausible cause of the increase of short-winged beetles in ageing populations. The higher fecundity of macropterous females makes them especially suited for (re)establishing populations.Communication No. 429 of the Biological Station WijsterPresent address and address for offprint requests: Kortenburg 31, NL-6871 ND Rentum     

Helminth community structure of the Mediterranean gull (Ichthyaetus melanocephalus) in Southern Italy

The helminth community of the Mediterranean gull (Ichthyaetus melanocephalus) from the Calabria region in southern Italy was examined. Ten species of helminths, including 2 cestodes (Alcataenia larina and Tetrabothrius cylindraceus), 4 digeneans ( Aporchis massiliensis , Brachylaima fuscatum, Cardiocephaloides longicollis, and Ornithobilharzia canaliculata), and 4 nematodes (Eucoleus contortus, Capillaria sp., Cosmocephalus obvelatus, and Paracuaria adunca), were found. The Mediterranean gull represents new host records for A. larina, A. massiliensis, B. fuscatum, and E. contortus; all species, except C. longicollis and O. canaliculata, constitute new locality records. The gastrointestinal helminth community of I. melanocephalus consisted of 9 species but, at the infracommunity level, species richness, diversity, and total helminth abundance are among the lowest reported from any gull species. Two cestode species accounted for 81% of all helminth specimens found.     

The evolutionary significance of wing dimorphism in carabid beetles (Coleoptera: Carabidae)

A review of data on the background of wing dimorphism in carabid beetles (Coleoptera: Carabidae) and especially of the closely relatedCalathus cinctus andC. melanocephalus is given. In bothCalathus species wing dimorphism is inherited in a simple Mendelian fashion with the brachypterous condition dominant, but inC. melanocephalus the expression of the long winged genotype is under environmental control as well. The development of long winged phenotypes in the latter species is favoured by relatively favourable environmental conditions, such as high temperatures and a high food-supply. The higher fecundity of the larger and heavier long winged females of both species may compensate for losses of long winged phenotypes by flight activities. The evolutionary significance of both types of inheritance is discussed in relation to dispersal. The ‘fixed type’ as found inC. cinctus is considered an opportunistic short term ‘between sites strategy’, whereas the ‘dynamic type’ ofC. melanocephalus represents a flexible long term ‘within sites strategy’.     

Moenkhausia celibela: a new species from the Amazon basin,Brazil (Characiformes: Characidae)

A new species of Characidae, Moenkhausia celibela, is described from the Rio Amazonas at Santarém, Rio Maraú, several localities in the Rio Tapajós, Rio Curuá‐Una, Rio Xingu and Rio Jari, all from the Amazon basin, Brazil. The new species is distinguished from its congeners, except species included in Géry's 1992 Moenkhausia lepidura group, by presenting a dark blotch on the upper caudal‐fin lobe, and the lower lobe is hyaline or light grey. Moenkhausia celibela is distinguished from the species of the M. lepidura group by the absence of a humeral spot and the presence of a roughly triangular and dark spot at the caudal‐fin base, extending posteriorly along the middle caudal‐fin rays, and distinctly separate from the spot on the upper caudal‐fin lobe.     

Euplectrus melanocephalus Girault (Hymenoptera: Eulophidae), an ectoparasitoid of larvae of fruit-piercing moths (Lepidoptera: Noctuidae: Catocalinae) from northern Queensland

Euplectrus melanocephalus is a gregarious, primary ectoparasitoid of larvae of the fruit-piercing moth genus Eudocima Billberg (Noctuidae: Catocalinae). In northern Queensland, E. melanocephalus parasitised second- and third-instar larvae of Eud. aurantia (Moore), Eud. cocalus (Cramer) , Eud. fullonia (Clerck), Eud. iridescens (Lucas), Eud. jordani (Holland) and Eud. materna (L.). In the laboratory, E. melanocephalus also parasitised Eud. salaminia (Cramer) but failed to oviposit on larvae of two other noctuids, Erebus terminitincta (Gaede) (Catocalinae) and Spodoptera litura (F.) (Amphipyrinae). When parasitising Eud. materna , eggs of E. melanocephalus were deposited dorsolaterally on one of the first five abdominal segments of second- and third-instar larvae. Fourth instars were occasionally parasitised when the density of parasitoids was increased, but successful development to adults was markedly reduced. Pupation took place between the leaf substrate and host. Female parasitoids provided with honey survived 21 days (range = 1–42) and deposited 112 eggs (range = 11–196), while development from egg to adult occupied 12–13 days at 25°C. The minimum temperature threshold for oviposition was 17.5°C, while minimum and maximum development thresholds for larvae were 18.5°C and 30°C, respectively. Studies on the parasitoid/host interactions of E. melanocephalus indicate that it is adapted principally to the larvae of Eudocima spp.     

The time of divergence between the two species of uacari monkeys: Cacajao calvus and Cacajao melanocephalus

It has been suggested in the literature that primates of the genus Cacajao have been restricted to flooded-forest habitats of western Amazonia since their split from the Chiropotes line in the Tertiary. It has been proposed further that the differentiation of the two species of this genus, Cacajao melanocephalus and Cacajao calvus, occurred during the Pleistocene period as a result of the fragmentation of the Amazon forest and the isolation of populations in these forest fragments or refuges. However, recent evidence has shown that at least C. melanocephalus is not dependent on flooded-forest habitats, and molecular analysis of mitochondrial DNA shows that the two species had already differentiated during the Pliocene, thus Pleistocene glaciations do not explain the speciation in Cacajao. Considering that C. melanocephalus and its closest relative, Chiropotes, inhabit terra firme forests, it is suggested that preference for flooded-forest habitats may be an apomorphy in C. calvus.     

Feeding Ecology of Black-headed Uacaris (Cacajao melanocephalus melanocephalus) in Pico da Neblina National Park,Brazil

From June 1994 to October 1995, I conducted a study of the feeding ecology of one group of black-headed uacaris (Cacajao melanocephalus melanocephalus) in Pico da Neblina National Park, Brazil, near the Venezuelan border (01°10N to 00°26S, 65°03W to 66°52W). Of a total of 429 feeding records, 89% corresponded to fruits from which black-headed uacaris ate ripe and unripe seeds, mesocarps and arils. Seeds were the single most important food item year-around, corresponding to 81% of the feeding records for fruits. Black-headed uacaris used 120 different plant species in 32 families as food. The 3 most important plant species in their diet, Micrandra spruceana, Eperua leucantha, and Hevea braziliensis (all trees), accounted for 38% of the feeding records for fruits. These species produced fruits that were protected by very hard green husks, were barochorous, did not have fleshy mesocarps, and were slow to mature, thus being available as unripe fruits for long periods. The second and third most important species in the diet of black uacaris, Eperua leucantha and Hevea braziliensis, were dominant in the forest: approximately 30% of trees 10 cm dbh sampled in a 2-ha botanical transect at the study site. I discuss the formation of large social groups of black-headed uacaris in Pico da Neblina National Park in light of the peculiar floristic composition of the study site.     

Range extension of the vulnerable dwarf marmoset, Callibella humilis (Roosmalen et al. 1998), and first analysis of its long call structure

We present two new records for the vulnerable dwarf marmoset, Callibella humilis. The first record, based on observed and photographed individuals, is from a campinarana area on the left (west) bank of the Rio Madeirinha, a left (west)-bank tributary of the Rio Roosevelt in the state of Amazonas, municipality of Novo Aripuanã and extends the distribution of the species ~270 km southwards, to the left (west) bank of the rio Roosevelt. The second record is based on an individual collected from the mouth of the Rio Roosevelt, at less than 10 km from the type locality of Mico marcai. This indicates that the species occurs sympatrically with M. marcai and probably Mico melanurus. We also present the first sonogram analysis of its long call structure, which shows some similarities, in the note duration and frequency, with Cebuella pygmaea and Mico argentatus.     

Nine polymorphic microsatellite loci for the parasitic wasp Neotypus melanocephalus (Hymenoptera: Ichneumonidae)

Nine polymorphic microsatellite loci were isolated from Neotypus melanocephalus (Gmelin), a parasitoid of the parasitic large blue butterfly Maculinea nausithous. Allelic diversity and heterozygosity were quantified in samples from the Upper Rhine valley in Southwest Germany.     

Observations onChiropotes albinasus from the Rio dos Marmelos,Amazonas, Brazil

Notes are presented on the body size, behaviour, diet, and gut morphology ofChiropotes albinasus from the Rio dos Marmelos in southeastern Amazonas state, Brazil. Findings include a new upper limit of body weight for the species, gut proportions consistent with its relatively high quality diet and evidence of geophagy.