The social behaviour of the hoary marmot (Marmota caligata)

The social behaviour of four colonies of hoary marmots (Marmota caligata) was studied in Glacier National Park, Montana, during the summer of 1970. Colony structure involved a dominant male with a few females (3 years or older), 2-year-olds, yearlings and pups. Patterns of burrow use, greetings, play, and aggressive chasing are described, indicating a closely-integrated social structure with reproductive patterns suggesting late dispersal and maturation. A close resemblance to the behaviour of the Olympic marmot (M. olympus) is proposed.     

Post-natal ontogeny of the mandible and ventral cranium in <Emphasis Type="Italic">Marmota</Emphasis> species (Rodentia,Sciuridae): allometry and phylogeny

Post-natal ontogenetic variation of the marmot mandible and ventral cranium is investigated in two species of the subgenus Petromarmota (M. caligata, M. flaviventris) and four species of the subgenus Marmota (M. caudata, M. himalayana, M. marmota, M. monax). Relationships between size and shape are analysed using geometric morphometric techniques. Sexual dimorphism is negligible, allometry explains the main changes in shape during growth, and males and females manifest similar allometric trajectories. Anatomical regions affected by size-related shape variation are similar in different species, but allometric trajectories are divergent. The largest modifications of the mandible and ventral cranium occur in regions directly involved in the mechanics of mastication. Relative to other anatomical regions, the size of areas of muscle insertion increases, while the size of sense organs, nerves and teeth generally decreases. Epigenetic factors, developmental constraints and size variation were found to be the major contributors in producing the observed allometric patterns. A phylogenetic signal was not evident in the comparison of allometric trajectories, but traits that allow discrimination of the Palaearctic marmots from the Nearctic species of Petromarmota are present early in development and are conserved during post-natal ontogeny.     

Spatial distribution of <Emphasis Type="Italic">Marmota baibacina</Emphasis> and <Emphasis Type="Italic">M. sibirica</Emphasis> (<Emphasis Type="Italic">Marmota</Emphasis>, Sciuridae,Rodentia) in a zone of sympatry in Mongolian Altai: Bioacoustic analysis

The spatial distribution of two marmot species Marmota baibacina and M. sibirica in a zone of coexistence was studied by using their alarm call as a diagnostic trait. It was found that M. baibacina prefers to inhabit bouldery screes, whereas M. sibirica inhabits all suitable biotopes. The difference in biotopic distribution of these species could be explained by M. sibirica forcing M. baibacina out of optimum habitats. Cases of coexistence of both species in one family group sites were registered, which might contribute to the appearance of hybrids.     

Isolation and characterization of microsatellite markers in hoary marmots (Marmota caligata)

Microsatellite loci were developed from hoary marmots (Marmota caligata) to aid in the investigation of the social structure and mating system of this species. Seven of the microsatellite loci developed were found to be moderately polymorphic with between two and seven alleles per locus. In addition to the microsatellites developed in hoary marmots we also tested markers developed for other scuirids, namely European alpine marmots (M. marmota), Columbian ground squirrels (Spermophilus columbianus) and European ground squirrels (S. citellus). Of these markers, 13 were polymorphic when amplified in hoary marmots with between two and nine alleles per locus.     

Winter weather versus group thermoregulation: what determines survival in hibernating mammals?

For socially hibernating mammals, the effectiveness of huddling as a means of energy conservation should increase with group size. However, group size has only been linked to increased survival in a few hibernating species, and the relative importance of social structure versus winter conditions during hibernation remains uncertain. We studied the influence of winter weather conditions, social group composition, age-structure, and other environmental factors and individual attributes on the overwinter survival of hoary marmots (Marmota caligata) in the Yukon Territory, Canada. Juvenile hoary marmot survival was negatively correlated with the mean winter (November to May) Pacific Decadal Oscillation (PDO) index. Survival in older age-classes was negatively correlated with PDO lagged by 1 year. Social group size and structure were weakly correlated with survival in comparison to PDO. The relationship between winter PDO and survival was most likely due to the importance of snowpack as insulation during hibernation. The apparent response of hoary marmots to changing winter conditions contrasted sharply with those of other marmot species and other mammalian alpine herbivores. In conclusion, the severity of winter weather may constrain the effectiveness of group thermoregulation in socially hibernating mammals.     

Freezing in a warming climate: Marked declines of a subnivean hibernator after a snow drought

Recent snow droughts associated with unusually warm winters are predicted to increase in frequency and affect species dependent upon snowpack for winter survival. Changes in populations of some cold‐adapted species have been attributed to heat stress or indirect effects on habitat from unusually warm summers, but little is known about the importance of winter weather to population dynamics and how responses to snow drought vary among sympatric species. We evaluated changes in abundance of hoary marmots (Marmota caligata) over a period that included a year of record‐low snowpack to identify mechanisms associated with weather and snowpack. To consider interspecies comparisons, our analysis used the same a priori model set as a concurrent study that evaluated responses of American pikas (Ochotona princeps) to weather and snowpack in the same study area of North Cascades National Park, Washington, USA. We hypothesized that marmot abundance reflected mechanisms related to heat stress, cold stress, cold exposure without an insulating snowpack, snowpack duration, atmospheric moisture, growing‐season precipitation, or select combinations of these mechanisms. Changes in marmot abundances included a 74% decline from 2007 to 2016 and were best explained by an interaction of chronic dryness with exposure to acute cold without snowpack in winter. Physiological stress during hibernation from exposure to cold, dry air appeared to be the most likely mechanism of change in marmot abundance. Alternative mechanisms associated with changes to winter weather, including early emergence from hibernation or altered vegetation dynamics, had less support. A post hoc assessment of vegetative phenology and productivity did not support vegetation dynamics as a primary driver of marmot abundance across years. Although marmot and pika abundances were explained by strikingly similar models over periods of many years, details of the mechanisms involved likely differ between species because pika abundances increased in areas where marmots declined. Such differences may lead to diverging geographic distributions of these species as global change continues.     

Inter- and Intraspecific Variation in the Acoustic Habitats of Three Marmot Species

Closely related species often have remarkably different vocalizations. Some of the variation in acoustic structure may result from species adapting their calls to maximize transmission through their acoustic environments. We document the relative magnitude of inter- and intraspecific variation in acoustic transmission properties of the habitats of three closely related marmot species to study the relative importance that the acoustic environment may have played in selecting for species-specific marmot alarm calls. We used spectrogram correlation to quantify the degree to which pure tones and alarm calls changed as they were broadcast through marmot home ranges to describe the acoustic habitats of golden (M. candata aurea), yellow-bellied (M. flaviventris), and alpine (M. marmota L.) marmots. Species lived in quantifiably different acoustic habitats. One analysis partitioned variation between species and between marmot social groups (nested within species). We found significant interspecific variation in the acoustic transmission fidelity of the three species' habitats and insignificant intraspecific variation between social groups. Further analysis of a larger sample of alarm calls broadcast through golden marmot social groups found significant intraspecific variation. Interspecific variation greater than intraspecific variation suggests that variable acoustic habitats may be responsible for at least some of the interspecific variation in alarm call structure. This is the first study to use spectrogram correlation to describe habitat acoustics. We discuss aspects of the method that may be useful for others seeking to quantify habitat acoustics.     

Beiträge zur Kenntnis der europäischen Raupenfliegen (Dipt. Tachinidae)

Summary In this revision of the European species of the genusMyxexoristops t. t. (parasites of sawflies) six species, including a new one (abietis n. sp., parasite ofCephalcia), are described by their distinguishing characters. Separate keys for the determination of males and females are given. For five species, hosts are recorded on the basis of bred material examined by the author himself.Zenillia nox hall, described from Japan is identical to the European speciesM. stolida stein (nov. syn.).      

Restudy and reassignment ofDentalium antiquum Goldfuss, 1841 (Middle Devonian)

Dentalium antiquum is one of two moderately well-known Devonian “scaphopods” in the German literature. Examination of the type material and a few specimens in other institutions indicates more individual variability than is to be expected in species of the molluscan class Scaphopoda. The species is transferred with question toColeolus Hall, a fossil presumed to be a calcareous “worm” tube.      

The species ofAphelinus Dalman, 1820 [Hymenoptera: Aphelinidae] from India

An account of the Indian species of the genusAphelinus Dalman is given Two new species (A. kashmiriensis sp. n.,A. desantisi sp.n.) are described. Four species (A. nikolskajae Jasnosh,A. flavipes (Foerster),A. abdominalis (Dalman),A. asychis Walker) are reported for the first time from India. A key for the separation of the Indian species ofAphelinus is presented.

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Résumé Deux nouvelles espèces (A. kashmiriensis, A. desantisi) sont décrites. Quatre espèces (A. nikolskajae Janosh,A. flavipes (Foerster),A. abdominalis (Dalman),A. asychis Walker) sont signalées pour la première fois de l’Inde. Une clé de détermination des espèces indiennes deAphelinus est présentée.

     

Habitat preferences in gray marmots (Marmota baibacina)

We examined habitat preferences of the Southern Altai subspecies of gray marmots (Marmota baibacina baibacina) both at the small and large scale. Considerable differences in habitat use among the gray marmot (sub)species complex have been described; Marmota kastschenkoi possibly represents the only forest-dwelling Palearctic marmot. Our results show that habitat use in Southern Altai marmots is determined mainly by vegetation type. The Altai marmots preferred grasslands and shrublands and their distribution was limited to the alpine zone above timberline. Marmots clearly avoided woodlands, even the forest edges and forest-steppe areas with a tree cover greater than 10 %. Gray marmots occur rarely in habitats occupied by alpine pikas, whereas presence of ground squirrels had no effect on marmot distribution. Altai marmots preferred mesic habitats with permeable subsoil layers. Livestock grazing and human disturbance did not affect marmot occurrence. Habitat requirements of examined Altai subspecies M. baibacina baibacina differ from the forest-steppe M. kastschenkoi; nevertheless, the ecological factors to which the forest-dwelling species responds remain to be analyzed. A recent speciation process in gray marmot complex was followed by the evolution of ecological requirements resulting in adaptation to forest dwelling.     

Tempo and mode of evolutionary divergence in modern and Holocene Vancouver Island marmots (Marmota vancouverensis) (Mammalia, Rodentia)

Marmota vancouverensis is the only insular species among the 14 species of marmots. The evolutionary history of this species is unresolved. Although M. vancouverensis is strongly differentiated in osteological and other morphological characters, its low genetic divergence suggests recent evolution from an ancestral continental species. We used geometric morphometric techniques to assess the morphology of hemimandibles from 239 modern M. vancouverensis , Marmota caligata , Marmota flaviventris , Marmota olympus and 30 Holocene (9435–735 cal. yr bp) subfossil M. vancouverensis . Our results confirm that the mandible of M. vancouverensis is strongly differentiated in shape from continental marmot species, but similar in size to its mainland sister species M. caligata . Temporal variation in size and shape over the past 2500 years among allochronic samples of M. vancouverensis was minimal suggesting that the morphological divergence of this species occurred in a period of rapid change following its isolation from mainland populations in the late Pleistocene. Selection pressures associated with environmental changes and founder effects and genetic drift resulting from population bottlenecks created by population declines and habitat fragmentation are hypothesized as factors contributing to the morphological divergence of this species.     

The Vegetation of Karachi

Summary The vegetation of Greater Karachi can be divided into three edaphic types.The coastal vegetation consists of three main associations. In the protected creeks facing the mouth of the rivers in shallow water is found mangrove vegetation consisting of mainly Avicennia alba Blume. In the muddy coastal swamps Arthroenemum indicum Moq is the main species. On the coastal sand dunes the main species consist of Suaeda monoica Forsk, Ipomaea pes-caprae Roth, Aerua pseudo-tomentosa Blatt and Hall, Calotropis procera Br. and Tamarix troupii, Hole.The vegetation of the calcarious rocks consists of mainly Commiphora mukul Engl., Grewia villosa Willd., Grewia tenax (Forsk) Boiss., Euphorbia caudicifolia Haines and Acacia senegal Willd.In the valleys between the hills where alluvium has been deposited over the basic rock by various rivers, the vegetation consists of Capparis decidua (Forsk) Edgew, Prosopis spicigera L. and Salvadora oleoides Dcne.

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Résumé La végétation de la région de Karachi peut être divisée en trois types trés différents au point de vue édaphique.La végétation littorale se compose de trois associations principales. Dans les criques protégées, en face des embouchures des fleuves, la végétation de la mangrove s'avance dans l'eau peu profonde. Elle consiste principalement d'Avicennia alba Blume. Dans les marais tourbeux du littoral, Arthrocnemum indicum Moq. occupe la première place. Sur les dunes littorales, les espèces principales sont Suaeda monoica Forsk, Ipomaea pes-caprae Roth., Aerua pseudo-tomentosa Blatt et Hall, Calotropis procera Br. et Tamarix troupii Hole.La végétation des rochers calcaires se compose principalement de Commiphora mukul Engl., Grewia villosa Willd., Grewia tenax (Forsk) Boiss., Euphorbia caudicifolia Haines et Acacia senegal Willd.Sur les alluvions des fleuves on note une végétation comprenant Capparis decidua (Forsk) Edgew, Prosopis spicigera L. et Salvadora oleoides Dcne.La végétation climax de la région est dominée par Salvadora oleoides Dcne et Prosopis spicigera L.

     

Effectiveness of recruitment behavior in stingless bees (Apidae,Meliponini)

Summary We examined the ability of stingless bees to recruit nest mates to a food source (i) in group foraging species laying pheromone trails from the food to the nest (Trigona recursa Smith, T. hypogea Silvestri, Scaptotrigona depilis Moure), (ii) in solitary foraging species with possible but still doubtful communication of food location inside the nest (Melipona seminigra Friese, M. favosa orbignyi Guérin), and (iii) in species with a less precise (Nannotrigona testaceicornis Lep., Tetragona clavipes Fab.) or no communication (Frieseomelitta varia Lep.). The bees were allowed to collect food (sugar solution or liver in the necrophageous species) ad libitum and the forager number to accumulate, as it would do under normal unrestrained conditions. The median number of bees collecting differed considerably among the species (1.0–1436.5). It was highest in the species employing scent trails. The time course of recruitment was characteristic for most of the species and largely independent of the number of foragers involved. The two Melipona species recruited other bees significantly faster than T. recursa, S. depilis, and N. testaceicornis during the first 10 to 30 minutes of an experiment. In species laying a scent trail to guide nestmates to a food source the first recruits appeared with a delay of several minutes followed by a quick increase in forager number. The median time required to recruit all foragers available differed among the species between 95.0 and 240.0 min. These differences can at least partly be explained by differences in the recruitment mechanisms and do not simply follow from differences in colony biomass.     

The successful introduction of the alpine marmot Marmota marmota in the Pyrenees,Iberian Peninsula,Western Europe

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Mallomonas alphaphora (Chrysophyceae), a new species from Western Australia

A new species ofMallomonas, M. alphaphora (Chrysophyceae), was found in freshwater ponds in the Perth region, Western Australia. It is distinguished from other species ofMallomonas by its very distinctive scale and bristle morphology and is placed in a new section,Alphaphorae, of the genusMallomonas. Dedicated to Prof. DrL. Geitler on the occasion of the 90th anniversary of his birthday.     

Delineations of forest fungi

Summary Several forest fungi, primarily species that occur in Mississippi, are discussed, and three species are described as new. These includeBotryobasidium (subgenusBrevibasidium)croceum Lentz,Tharoopama mississippiensis Lentz, andHarpographium zonatum Lentz.Dactylium leptosporum (Sacc.)Lentz is recognized as a distinct species, rather than as a subspecies ofD. dendroides Fr. Allescheriella crocea (Mont.)Hughes,D. leptosporum andMelanographium cookei M. B. Ellis are reported from Mississippi for the first time. Attention is called to the fact thatM. citri (Fragoso &Ciferri)M. B. Ellis apparently has not previously been reported from the United States, although a specimen from Florida is in the National Fungus Collections.B. croceum evidently represents the basidiophorous stage ofA. crocea.     

Key to palaearctic species of the genusPsyllaephagus [Hym.:Encyrtidae]

The article contains a key to 42 species of the genusPsyllaephagus Ashmead, 1900—parasites ofPsylloidea, mainly from southern regions of Palaearctics.Psyllaephagus tobiasi Trjapitzin, 1967 is synonymized withP. belanensis (Hoffer, 1963).

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Résumé Il est fourni la clé de 42 espèces du genrePsyllaephagus Ashmead, 1990, parasites de psylles, principalement des régions méridionales de la zone paléarctique.Psyllaephagus tobiasi Trjapitzin, 1967 est mis en synonymie avecP. belanensis (Hoffer, 1963).