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1.
Nesting by multiple females in sweat bees raises the question of the benefits associated with grouping. Adult numbers of the
sweat bee, Lasioglossum (Evylaeus) baleicum, exhibited variation within a nest population. The effects of adult number and nest position on larval survival were analyzed
in a nest aggregation. Both variables independently affected larval survival, with the presence of multiple adults in a nest
markedly improving survival rate. Nests located near the periphery of the aggregation of nests suffered high larval mortalities.
Increased frequency of cell-inspection in multiple-female nests seems to be associated with a concomitant increase in larval
cell protection from external predation. Such predation pressure was assumed, given the existence of an underground ant colony
that employs a recruitment system while foraging in the study area. 相似文献
2.
We have investigated the floral ontogeny of Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis (of the eucalypt group, Myrtaceae) using scanning electron microscopy and light microscopy. Several critical characters for establishing relationships between these genera and to the eucalypts have been determined. The absence of compound petaline primordia in Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis excludes these taxa from the eucalypt clade. Post-anthesis circumscissile abscission of the hypanthium above the ovary in Stockwellia, Eucalyptopsis and Allosyncarpia is evidence that these three taxa form a monophyletic group; undifferentiated perianth parts and elongated fusiform buds are characters that unite Stockwellia and Eucalyptopsis as sister taxa. No floral characters clearly associate Arillastrum with either the eucalypt clade or the clade of Stockwellia, Eucalyptopsis and Allosyncarpia.We gratefully acknowledge Clyde Dunlop and Bob Harwood (Northern Territory Herbarium) for collecting specimens of Allosyncarpia, and Bruce Gray (Atherton) for collecting specimens of Stockwellia. The Australian National Herbarium (CANB) kindly lent herbarium specimens of Eucalyptopsis for examination. This research was supported by a University of Melbourne Research Development Grant to Andrew Drinnan. 相似文献
3.
Carreras-Aubets M Repullés-Albelda A Kostadinova A Carrassón M 《Systematic parasitology》2011,79(2):145-159
The status of the trematode Aponurus laguncula Looss, 1907 in the western Mediterranean is re-assessed by means of a comparative morphological study and rDNA sequences
based on newly collected material. A. laguncula (sensu stricto) is redescribed from Trachinus draco L. and a new cryptic species of the ‘A. laguncula complex’, Aponurus mulli n. sp., is described on the basis of abundant material from Mullus barbatus L. (type-host) and M.
surmuletus L. off the Spanish Mediterranean coasts. The new species is differentiated from A. laguncula (sensu stricto) by its: significantly larger, elongate body, with maximum width at the level of the ventral sucker; shorter forebody; distinctly
larger sinus-sac, seminal receptacle and seminal vesicle, with the latter also being more elongate; vesicular pars prostatica;
more anteriorly located vitellarium, which consists of eight globular follicles; and distinctly smaller eggs, which are also
smaller in relation to body size and have both their opercular and anopercular poles rounded. The variability and the allometric
growth of the morphological characters in the new species were studied in detail, resulting in additional distinguishing features.
Sequences of the large subunit rRNA (28S) gene (domains D1–D3) and ITS2 rRNA gene region for the new species have been submitted
to GenBank in order to enhance future studies on species differentiation within the ‘A. laguncula complex’. 相似文献
4.
A new trematode genus, Grammatorcynicola n. g. (Bucephalidae: Dolichoenterinae), and two new species, G. brayi n. sp. and G. nolani n. sp. from the intestines of the scombrids, Grammatorcynus bicarinatus and Gr. bilineatus respectively, are reported from the Great Barrier Reef, Australia. Grammatorcynicola n. g. is placed in the Dolichoenterinae, as the pharynx is in the anterior quarter of the body, the caecum is tube-like and extends to the posterior quarter of the body, the cirrus-sac is small relative to the size of the worm when compared with other bucephalids and the pars prostatica is curved. Grammatorcynicola n. g. differs from other dolichoenterine genera in having a simple sucker-like rhynchus, the ovary anterior to the testes and by not having a particularly thick cirrus-sac wall. 相似文献
5.
Mahinda Martínez Luis Hernández-Sandoval Lilia Carrillo 《Plant Systematics and Evolution》2014,300(10):2249-2258
Beaucarnea (Nolinaceae) is a Mexican and Guatemalan genus that inhabits dry tropical areas. Most of the species are endangered under the Mexican legislation because they have a high horticultural demand and are threatened by habitat destruction. Species are difficult to recognize, since their differences are a mixture of trunk, inflorescence and fruit characters frequently absent in herbarium specimens. The aim of this work is to describe the foliar anatomy of the 11 species of Beaucarnea in search of characters with taxonomic value to sustain the generic subdivision, and to provide a key for specimens determination based on leaf and growth form. We found that four species (B. compacta, B. gracilis, B. purpusii and B. stricta) have a grooved leaf outline in transverse section, whereas the rest of the species are undulated. Other characters, such as epicuticular waxes, stomatal distribution and density, marginal teeth length and leaf apex provide valuable characters for species determination. 相似文献
6.
Proctocaecum gairhei n. sp. is described from the gharial Gavialis gangeticus (Gmelin) in Nepal. The new taxon can be distinguished from all other species of Proctocaecum Baugh, 1957 by the combination of the following morphological characters: a single row of 23 cephalic spines, lateral anal pores opening at uneven levels, a forebody accounting for 16% of the total body length (TBL), an oral to ventral sucker width ratio of 1:0.7, an oral sucker to pharynx width ratio of 1:0.6 and uterine loops that occupy 59-67% of the TBL. While sharing some morphological characteristics with Acanthostomum slusarskii Kalyankar, 1977 from Crocodylus palustris (Lesson) in India, P. gairhei n. sp. is distinguished from the latter by possessing the solid muscular gonotyl diagnostic for Proctocaecum, by the number of cephalic spines, position of the anal pores and egg size. The existing cladogram for Proctocaecum was expanded using the character information of P. gairhei n. sp. The host range of Proctocaecum is now known to include all three families of the order Crocodylia. 相似文献
7.
8.
Johnius (Johnius) majan sp. nov. is described on the basis of 8 specimens (117–158 mm in standard length) from Oman, Indian Ocean. The new species
is distinguished from its congeners by the following combination of characters: black axillary spot on upper pectoral fin
base; dorsal soft rays 29–32; anal soft rays 8; scales above lateral line 6, below 11; eye diameter 22.9–28.9% HL; interorbital
width 32.0–38.0% HL; gill rakers 5–6 + 15–18 = 21–24; no mental barbel; last well developed pleural rib on 7th vertebra; swim
bladder appendages 11; vertebrae 10 + 14 = 24. 相似文献
9.
10.
Four species of monocotylid monogeneans were found on a spotted eagle ray Aetobatus cf. narinari caught off Noumea, New Caledonia, South Pacific. The host is illustrated for future possible identification, because it belongs to a currently unresolved species complex. Decacotyle octona (Young, 1967) Chisholm & Whittington, 1998, from the secondary gill lamellae, is figured and previously unreported details of the reproductive system are described. D. elpora n. sp. is described from numerous specimens found between the secondary gill lamellae. The new species, 780-1650 microm in body length, is smaller than D. octona, but has a longer sclerotised male copulatory organ. It is characterised by two dorsal haptoral accessory structures, each with three bumps, and a 9-shaped sclerotised male copulatory organ 240-290 microm in length. D. octona and Clemacotyle australis Young, 1967, both from the branchial cavity, and Thaumatocotyle pseudodasybatis Hargis, 1955, from the nasal tissue, are new geographical records for New Caledonia. It is suggested that differences in the monocotylid fauna between the Atlantic and Indo-Pacific forms of Aetobatus cf. narinari could be of interest for the systematic status of the ray, but the sporadic nature of the sampling probably casts doubt on the usefulness of the currently available data. 相似文献
11.
Species delimitation in the genus Geopora (Pyronemataceae) is complicated because of small number of differentiating characters, values of which tend to overlap among
the species. Current classification relies mainly on size and shape of ascospores and fruit-bodies, position of the apothecia
in the ground and length of excipular hairs. We measured ascospores in ca. 90 Geopora specimens. Sequences of internal transcribed spacer (ITS) rDNA gene were obtained to investigate phylogenetic relationships
in the genus. Maximum parsimony (MP) and Bayesian analyses reveal that the well-supported clades detected often do not correspond
to the species concepts based on morphological characters. Nine out of the ten lineages include specimens which were initially
identified as belonging to different species. The dimensions of ascospores vary to great extent within the lineages. The size
and shape of fruit-bodies, length of excipular hair and hymenium colour are mostly homogenous within each clade; however,
these characters coincide to a great extent among the lineages and the latter can be assessed only from fresh fruit-bodies.
Nuclear DNA content, and accordingly, ploidy level do not provide evidence for species distinction. Geopora arenicola, G. tenuis and G. sepulta were recognized as monophyletic species. Geopora foliacea and G. cervina could not be explicitly delimited and the G. cervina complex comprising three clades was introduced. 相似文献
12.
Ana Nunes dos Santos Allan Rodrigo de Oliveira Rodrigues Fábio José dos Santos Rocha Jeannie Nascimento dos Santos Cynthya Elizabeth González Francisco Tiago de Vasconcelos Melo 《Systematic parasitology》2018,95(2-3):293-300
Neocosmocercella fisherae n. sp. is the first nematode species found parasitising Phyllomedusa bicolor from the Brazilian Amazon Region. The new species has a triangular oral opening, with bi-lobed lips, and is distinguished from N. bakeri (triangular oral opening with simple lips), and from N. paraguayensis (hexagonal oral opening with bi-lobed lips). Additionally, the new species has ciliated cephalic papillae, which are absent in the other species of the genus. The reduced uterine sac and the presence of a single egg in the uterus in females are the main morphological characters that differentiate the new species from its congeners N. bakeri (8–10 eggs) and N. paraguayensis (10 eggs, based on the allotype). Additionally, the new species differs from the other two species of the genus by morphometric characters such as the size of spicules and gubernaculum in males and the vagina in females. Until now, phyllomedusid anurans are the only known hosts for the nematodes of this genus. The present work describes the third species of the genus and the first species of nematode parasitising P. bicolor. 相似文献
13.
Cetorhinicola acanthocapax Beveridge & Campbell, 1988 is redescribed based on adult specimens collected from a basking shark Cetorhinus maximus (Gunnerus) off the east coast of New Zealand. Both the mature and gravid segments are described for the first time, and the first scanning electron micrographs of the armature and scolex microtriches are provided. Novel features include the opening of the vagina anterior to the cirrus-sac and the extension of the vagina anterior to the cirrus-sac. Pectinate microtriches are present on the anterior quarter of the pars pedunculus scolecis scattered between filiform microtriches; the bothrial margins are covered with tridigitate microtriches, while the adherent surface of the bothria have pectinate microtriches. The additional morphological features described are consistent with a close association between Cetorhinicola Beveridge & Campbell, 1988 and the Eutetrarhynchoidea Guiart, 1927. 相似文献
14.
Based on light and scanning electron microscopical observations, Typhlophoros kwenae n. sp. (Heterocheilidae), a new nematode parasite, is described from the stomach of the Nile crocodile Crocodylus niloticus Laurenti in South Africa. In having three lips with well-developed posterior prolongations and prominent interlabial longitudinal cuticular ridges, four pairs of precloacal papillae and complex spicules divided into handle and broad alate blade in males, as well as the position of the vulva near mid-body in females, the specimens conform to the generic diagnosis of Typhlophoros von Linstow, 1906. They can, however, be distinguished from the two previously described congeners, T. lamellaris von Linstow, 1906 and T. spratti Sprent, 1999, by the number of complete interlabial ridges, the length of spicules in males and the position of the vulva as well as the length of the tail in females. This is the first record of the genus Typhlophoros from the Afrotropical Realm. 相似文献
15.
Petasiger islandicus n. sp. is described and figured from a demographically isolated population of the horned grebe Podiceps auritus auritus (L.) in Lake Myvatn (Iceland). This new species belongs to the group of species with 19 collar spines which possess a large elongate-oval cirrus-sac, well-developed pars prostatica and massive bulb-like cirrus. Within this group, P. islandicus appears most similar to P. oschmarini Kostadinova & Gibson, 1998, a form with similar body dimensions described from the same host, but differs in having a larger head collar, collar spines, oral sucker, pharynx, testes and sucker-width ratio, and a smaller cirrus-sac, cirrus and eggs. Two Nearctic species resemble P. islandicus in general morphology but differ as follows: P. pseudoneocomense Bravo-Hollis, 1969 has a larger body and collar width, notably shorter collar spines, smaller testes and sucker-width ratio, and a shorter but much wider cirrus-sac which is also smaller relative to the ventral sucker and almost entirely anterior to it; and P. caribbensis Nassi, 1980 has a smaller body, shorter collar spines and a seminal vesicle which is small in relation to the cirrus-sac, vitelline fields reaching anteriorly to the level of the genital pore and the intestinal bifurcation is located more anteriorly. 相似文献
16.
A new species of Notocotylus was found parasiting a freshwater pulmonate snail, Biomphalaria peregrina. Naturally infected snails were collected from two temporary ponds in the Nahuel Huapí National Park in Patagonia. The characteristics of the larval stages are presented. Experimental adults were recovered from the intestinal caeca of ducks and chicks. Adults of Notocotylus biomphalariae n. sp. exhibit an aspinose tegument, two lateral rows of 11 ventral glands and a median row of four, a uterus with 12–16 coils of which 2–4 are previtelline, a metraterm equivalent in size to 65–68% of the cirrus-sac length, a previtelline field which extends to the middle of the body, a lobed testis and a genital pore closely posterior to the intestinal bifurcation. The rediae have one to three cercariae. The cercariae, when shed, are trioculate and have a long tail; they encyst in the environment and become infective 12 days after encystment. 相似文献
17.
A multivariate analysis has been performed in order to study the polymorphisms of the three species ofPotentilla sect.Recta (Th. Wolf)Juzepchuk represented in the Iberian Peninsula:P. asturica
Rothm.,P. hirta L. andP. recta L. The variability of 20 characters (quantitative, binary and qualitative) has been evaluated in 76 collections mostly from
the Iberian Peninsula and from other European territories, but also from North America, and North Africa. The analyses performed
provide support for the recognition of the three species. The most discriminant among the quantitative characters is the width
of the long trichomes on the stem, and then the width of the long trichomes on the leaves and the maximum length of the long
trichomes. The interval of number of carpels, presence or absence of short eglandular trichomes and the abundance of long
eglandular trichomes (>3 mm) are the most discriminant ones among the qualitative ones. The taxonomical position ofP. asturica, which has been previously subordinated as a subspecies within the other two taxa, is discussed. Our results support a good
delimitation of this taxon which, on the basis of the morphological characters studied by us, seems to be morphologically
more close toP. hirta than toP. recta, but differs significantly from both. A key to the three species is provided. 相似文献
18.
Nafiseh Sanjarani Vahed Hamid Reza Esmaeili Mojtaba Masoudi Bettina Reichenbacher 《Environmental Biology of Fishes》2018,101(9):1309-1317
Otolith morphology in the tooth-carp/killifish genus Aphanius is a source of informative taxonomic characters at both the species and population level. Most work on otoliths has focused on adult specimens, while evidence of ontogenetic variation is rarely provided. In this study we describe the development of otolith morphology during the early life stages of an endangered and endemic species, the Fars tooth-carp Aphanius farsicus from southern Iran. The study material comprises 34 larvae and early juveniles representing nine different developmental stages (0–120 days post hatching), all reared under the same laboratory conditions. The results reveal (i) a significant correlation between standard length and otolith size (length) in larval and early juvenile stages, (ii) clear differences in otolith morphology between larvae/early juveniles and adults, and (iii) a temporal link between the appearance of the sulcus on the otolith’s inner face and the emergence of the dorsal and anal fins. Our results indicate that otoliths of Aphanius can be recognized as originating from larval or early juvenile fish based on their short rostrum and antirostrum lengths and wide excisura, in addition to their small size. These immature otoliths are, however, not diagnostic at the species level in A. farsicus, nor most probably in other species of tooth-carp. The outcome of our study is also of interest to palaeontologists working with fossil killifish otoliths, as it can help avoid misinterpretation of ancient species diversity. 相似文献
19.
Chelidoperca tosaensis is described as a new species based on 84 specimens from Japan and the Philippines taken from depths of 60–302 m. The species can be distinguished from all known congeners by having the following combination of characters: scale rows between lateral line and base of spinous dorsal fin 3; pored lateral-line scales 37–42 (modally 39); scale rows in longitudinal series 39–43 (modally 40); no longitudinal dark stripe or row of dark blotches on body side. The new species is additionally characterized by having a combination of numerous, scattered, yellow spots on dorsal and anal fins with red streak or cluster of reddish spots over bases of about 4–6th dorsal-fin spines; large ocellated red spot with pinkish white border present on membrane between opercular spines; pelvic fin with middle area yellow with whitish spine, and whitish first, second and fifth soft rays; caudal fin with about three transverse rows of yellow spots centrally and posteriorly, two fan-shaped rows of red blotches on basal third, and a pair of white blotches with a pair of yellow blotches between white blotches on the base. Diagnostic characters of Chelidoperca stella, previously known only from its type locality in the Andaman Sea, are updated based on 12 specimens from Taiwan, the Gulf of Tonkin, Vietnam and the Philippines. These specimens represent the first records of the species from the Pacific Ocean. 相似文献