Implications of a comparison of the airbourne vocalizations and some aspects of teh behaviuo of the two Australian fur seals, Arctocephalus spp., on the evolution and present taxonomy of the genus

1971 ◽  
Vol 19 (3) ◽  
pp. 227 ◽  
Author(s):  
I Stirling ◽  
RM Warneke

The structure and number of airborne vocalizations of Arctocephalus pusillus doriferus and A. forsteri were studied. Four types of calls were compared: the pupattraction call given by adult females; the female-attraction call given by pups; the high-intensity guttural threat given by adult males; and, the repetitive barking call given by adult males. Male A. fovsteri gave two additional threat calls not present in A. p. doriferus. The structure and number of the calls given by the two species are substantially different. They here then compared to the calls of other members of the genus for which data were available and it became evident there were two vocal types within the genus Arctocephalus. We believe this is the first time such a situation has been reported in mammals. In addition to vocalizations, data on behaviour and morphology are presented to show the enigmatic taxonomic position, between the fur seals and the sea lions, occupied by A. pusillus.

Zootaxa ◽  
2011 ◽  
Vol 2983 (1) ◽  
pp. 39 ◽  
Author(s):  
IVAN L. F. MAGALHÃES ◽  
ADALBERTO J. SANTOS

In this paper, M. yanomami n. sp., from Brazilian Amazonia, Chaetacis bandeirante n. sp., from Central Brazil, and the males of M. gaujoni Simon, 1897 and M. ruschii (Mello-Leitão, 1945) n. comb. , respectively from Ecuador and Brazil, are described and illustrated for the first time. An ontogenetic series of the last development stages of both sexes of Micrathena excavata (C. L. Koch, 1836) is illustrated and briefly described. Adult females are larger and have longer legs and larger abdomens than adult males. Probably females undergo at least one additional moult before adulthood, compared to males. Micrathena ornata Mello-Leitão, 1932 is considered a junior synonym of M. plana (C. L. Koch, 1836), and M. mastonota Mello-Leitão 1940 is synonymized with M. horrida (Taczanowski, 1873). Acrosoma ruschii Mello-Leitão, 1945 is revalidated, transferred to Micrathena and considered a senior synonym of M. cicuta Gonzaga & Santos, 2004. Chaetacis necopinata (Chickering, 1960) is recorded for Brazil for the first time. Chaetacis incisa (Walckenaer, 1841) is considered a nomen dubium.


2015 ◽  
Vol 72 (2) ◽  
pp. 175-185 ◽  
Author(s):  
Kathryn L. Sweeney ◽  
Kyle W. Shertzer ◽  
Lowell W. Fritz ◽  
Andrew J. Read

We utilized aerial images and employed photogrammetric methodologies to collect standardized lengths of Steller sea lions (Eumetopias jubatus) terrestrially hauled out. We conducted comparisons among all site types and separately for rookery and haulout site-types between the two distinct population segments (DPSs; eastern and western) and two broad regions within the western DPS experiencing contrasting population abundance trends. An observed adult female index was created from measurements of reproductive females — in the presence of a pup or juvenile — and was applied as a model constraint for “adult females”. We fitted a finite mixture distribution model to the length-frequency data to estimate the proportion population for three delineated age–sex classes (juveniles, adult females, and adult males) and mean length for juveniles and adult males. Estimated proportions reflected what we expected; however, the broad region within the western DPS exhibiting substantial population declines had greater proportion of all age–sex classes on rookery sites than increasing broad region. Adult sea lions were significantly shorter in the eastern DPS than the western area, providing further evidence of morphological differences between the DPSs. We also introduce a less resource-demanding method for estimating population demographics, and potentially vital rates, for pinnipeds across a vast geographic range.


1993 ◽  
Vol 71 (9) ◽  
pp. 1908-1911 ◽  
Author(s):  
Robert Harcourt

Southern sea lions (Otaria byronia) were observed to prey on juvenile and adult female South American fur seals (Arctocephalus australis) at Punta San Juan, Peru (15°22′S, 75°12′W) between October 1987 and December 1988. Over the course of the study there were 165 attacks on fur seals with 33 seals killed. While both adult male and subadult male sea lions captured and killed fur seals, adult female and juvenile sea lions never acted aggressively towards fur seals. Adult males attacked fur seals on 82.4% of the occasions when they were present at the rookery, subadults on 52% of occasions. Distinctive pelage characteristics allowed some of the male sea lions to be individually identified, and differences in hunting success were observed between adults and subadults, and between five identifiable adults who hunted on at least five occasions. Motivation for attacks differed for subadults and adults, with subadult males using captured fur seals as female sea lion substitutes, guarding them from others and copulating with them, whilst adult sea lions hunted fur seals as food. However, only a small proportion of adult sea lions hunted fur seals, and with differing rates of success.


Check List ◽  
2018 ◽  
Vol 14 (4) ◽  
pp. 657-663
Author(s):  
Scott A. Grubbs ◽  
Mwenda M. Singai

New and prior valid records of the endemic eastern Nearctic species Rasvena terna (Frison, 1942) were compiled and a dot distribution map is provided. Rasvena terna is reported from Canada (Quebec) for the first time. External reproductive morphology of adult males and adult females were studied across this species range. Scanning electron microscopy images of reproductive structures and the larval mandible are presented for the first time.


1979 ◽  
Vol 57 (1) ◽  
pp. 140-148 ◽  
Author(s):  
E. H. Miller ◽  
D. J. Boness

Adult males of the grey seal, Halichoerus grypus (Fab.) (Phocidae), display the large snout conspicuously in threats. The male's snout has probably evolved through sexual selection as a visual display organ, as in some other extant phocids: the hooded seal, Cystophora cristata (Nilsson) and the two species of elephant seals, Mirounga (Gray). This may also be true of the extinct desmatophocid Allodesmus Kellogg. Cephalic display organs in the form of long tusks have also evolved twice in the Odobenidae (walruses). Comparable display structures do not occur in the Otariidae (fur seals and sea lions). However, the massive neck of adult male otariids is important in undirected static-optical threat displays, especially at long range, and in some kinds of short-range threats. Also, adult otariids show sexual dimorphism in facial appearance, which varies interspecifically.Pinniped species in which large mature males have prominent, constant-growing cephalic display structures show fluid spacing among rutting males, and much agonistic communication at the water surface and on land or ice. This correlation may reflect selective pressures on males to affirm social status repeatedly, through displays which communicate their age (hence strength and experience), and their resource-accruing abilities.


Zoosymposia ◽  
2012 ◽  
Vol 8 (1) ◽  
pp. 56-68 ◽  
Author(s):  
HIROKO OKAWACHI ◽  
DAISUKE UYENO ◽  
KOTARO OGINO ◽  
KAZUYA NAGASAWA

Infections with the pennellid Peniculus minuticaudae Shiino, 1956 occurred on three species of marine fishes, the unicorn leatherjacket filefish, Aluterus monoceros (L.), the hairfinned leatherjacket, Paramonacanthus japonicus (Tilesius), and the brown-banded butterflyfish, Roa modesta (Temminck & Schlegel), held at a public aquarium in Kagoshima, Japan. Using specimens from the aquarium and type material, the postmetamorphic and premetamorphic adult females of P. minuticaudae are redescribed. The adult male, copepodid I, and late chalimus stages are described for the first time. The three fish species represent new host records for P. minuticaudae. Fishes were found heavily infected with P. minuticaudae, and extensive lesions associated with infections were found on the skin and around the fin rays of R. modesta. While pennellids usually use two hosts during their life cycle, it is very likely that P. minuticaudae completes its life cycle using one host, as suggested by copepodids, chalimi, adult males, premetamorphic adult females, and postmetamorphic adult females of the parasite all being found on a single fish.


2018 ◽  
Vol 52 (3) ◽  
pp. 181-192 ◽  
Author(s):  
O. I. Lisitsyna ◽  
O. Kudlai ◽  
T. R. Spraker ◽  
T. A. Kuzmina

Abstract To increase the currently limited knowledge addressing acanthocephalans parasitizing California sea lions (Zalophus californianus), 33 animals including pups, juvenile and adult males and females from the Marine Mammal Center (TMMC), Sausalito, California, USA were examined. Totally, 2,268 specimens of acanthocephalans representing five species from the genera Andracantha (A. phalacrocoracis and Andracantha sp.), Corynosoma (C. strumosum and C. obtuscens) and Profilicollis (P. altmani) were found. Profilicollis altmani and A. phalacrocoracis, predominantly parasitize fish-eating birds; they were registered in Z. californianus for the first time. Prevalence and intensity of California sea lion infection and transmission of acanthocephalans in these hosts of different age groups were analyzed and discussed. We provide brief morphological descriptions of the five species of acanthocephalan found in California sea lions.


2013 ◽  
Vol 47 ◽  
pp. 68-73
Author(s):  
S. V. Volobuev

The corticioid basidiomycete Jaapia ochroleuca (Bres.) Nannf. et J. Erikss. is recorded for the first time in the European Russia from the «Bryansky Les» Nature Reserve (Bryansk Region). The taxonomic position of the species is defined briefly. Its morphological description and data on distribution and ecology are provided. The details of microscopic structure of the collected specimen are illustrated.


Biology ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 420
Author(s):  
Gabriel Biffi ◽  
Simone Policena Rosa ◽  
Robin Kundrata

Jurasaidae are a family of neotenic elateroid beetles which was described recently from the Brazilian Atlantic Forest biodiversity hotspot based on three species in two genera. All life stages live in the soil, including the larviform females, and only adult males are able to fly. Here, we report the discovery of two new species, Jurasai miraculum sp. nov. and J. vanini sp. nov., and a new, morphologically remarkable population of J. digitusdei Rosa et al., 2020. Our discovery sheds further light on the diversity and biogeography of the group. Most species of Jurasaidae are known from the rainforest remnants of the Atlantic Forest, but here for the first time we report a jurasaid species from the relatively drier Atlantic Forest/Caatinga transitional zone. Considering our recent findings, minute body size and cryptic lifestyle of all jurasaids, together with potentially high numbers of yet undescribed species of this family from the Atlantic Forest and possibly also other surrounding ecoregions, we call for both field research in potentially suitable localities as well as for a detailed investigation of a massive amount of already collected but still unprocessed materials deposited in a number of Brazilian institutes, laboratories and collections.


1994 ◽  
Vol 72 (7) ◽  
pp. 1314-1324 ◽  
Author(s):  
D. G. Reid ◽  
T. E. Code ◽  
A. C. H. Reid ◽  
S. M. Herrero

Seasonal spacing patterns, home ranges, and movements of river otters (Lontra canadensis) were studied in boreal Alberta by means of radiotelemetry. Adult males occupied significantly larger annual home ranges than adult females. Males' ranges overlapped those of females and also each other's. In winter, home ranges of males shrank and showed less overlap. Otters often associated in groups, the core members typically being adult females with young, or adult males. Otters tended to be more solitary in winter. In winter, movement rates of all sex and age classes were similar, and much reduced for males compared with those in other seasons. These data indicated a strong limiting effect of winter ice on behaviour and dispersion. We tested the hypothesis that otters select water bodies in winter on the basis of the suitability of shoreline substrate and morphology for dens with access both to air and to water under ice. Intensity of selection was greatest in winter, with avoidance of gradually sloping shorelines of sand or gravel. Adults selected bog lakes with banked shores containing semi-aquatic mammal burrows, and lakes with beaver lodges. Subadults selected beaver-impounded streams. Apart from human harvest, winter habitats and food availability in such habitats are likely the two factors most strongly limiting otter density in boreal Alberta.


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