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1.
ABSTRACT

Ophiocordyceps is a genus comprised by entomopathogenic fungi known to infect ten orders of insects, including Hymenoptera. Amongst the nearly 250 species described in the genus, few are known to manipulate their hosts, which are most notably ants. These species cause their hosts to die in an exposed position high above the ground while grabbing and/or biting the abaxial surface of leaves or branches, which in turn optimizes the fungus spore production and dispersal. Herein, we report on 14 social wasp species belonging to four genera (Agelaia, Mischocyttarus Polybia, and Pseudopolybia) infected by Ophiocordyceps humbertii, a common wasp pathogen. This study broadens the geographic and host range for O. humbertii and provides the first record of its ability to manipulate its host.  相似文献   

2.
Didymodon kunlunensis D.P.Zhao, S.Mamtimin & S.He is described as a new species found in Xinjiang, China. The new species is characterised by a combination of the following characters: ovate leaves with laminal cells always smooth, red colour in KOH, recurved leaf margins from base to apex, a percurrent costa without dorsal and ventral stereid bands in cross section, a distinct stem central strand and the presence of gemmae in the leaf axils. Light microscope photographs of the significant characters are provided and its distinctions from closely related taxa are discussed. A key to Chinese Didymodon species with smooth laminal cell is provided.  相似文献   

3.
Photoinhibition in differently coloured juvenile leaves of Syzygium species   总被引:1,自引:0,他引:1  
Photoinhibition, as measured by the dark-adapted chlorophyll a fluorescence ratio Fv/Fm, was assessed in Syzygium moorei, a species with dark green juvenile leaves, Syzygium corynanthum, which has light green juvenile leaves, and two species with pink-red juvenile leaves (Syzygium wilsonii and Syzygium luehmannii). All plants were glasshouse-grown (maximum PPFD 1500 mol m-2 s-1) under optimum nutrition and water.When measured at midday, dark-adapted Fv/Fm ratios of juvenile leaves gradually increased in all species as percentage of full leaf expansion (% FLE) increased. Fluorescence measurement 3h after sunset or pre-dawn also showed a developmental effect on Fv/Fm, with juvenile leaves of S. luehmannii and S. wilsonii showing much lower Fv/Fm at all stages of development. Dark-adapted Fv/Fm, values in both juvenile and mature leaves generally never exceeded 0.8 at any stage in any of the species.Courses of Fv/Fm on sunny days showed greater diurnal photoinhibition in green juvenile (c. 50% FLE) leaves of S. moorei (24%) and S. corynanthum (36%) than in mature leaves of the previous flush in these species (<10%). Diurnal photoinhibition was statistically similar (18-24%) in pink-red juvenile and green mature leaves of S. luehmannii and S. wilsonii. Re-positioning juvenile leaves of S. wilsonii horizontally increased diurnal photoinhibition.Exposure of leaves to a standard mild photoinhibitory light treatment (30 min at 1000 mol m-2s-1) showed that juvenile leaves of all species had a lower percentage of high energy state quenching (qE) and a higher percentage of photoinhibitory quenching (qI) than mature leaves.  相似文献   

4.
A new species of Cercestis (Araceae), C. hepperi Jongkind from Liberia is described and illustrated. It is characterised by comparatively long pedunculate inflorescences, very dark green leaf blade with a conspicuous yellow margin and short basal lobes and by abundant stolons with persistent scaly leaves (cataphylls). Cercestis sagittatus Engler, another species from Liberia, that was synonymised with C. dinklagei Engler by Ntépé‐Nyamè, is resurrected. A key to the species of Cercestis known from Liberia is provided.  相似文献   

5.
A new species of Plagiomnium (Mniaceae), P. guizhouense Y.-J.Yi & S.He from Guizhou, China is described and illustrated. The new species is similar to P. affine in having spinosely serrate leaf margins with teeth consisting of up to 4 or more cells, a broadly elliptic leaf shape, and a decurrent leaf base, but is distinguished from the latter species by having a cuspidate leaf apex, broader marginal differentiation with borders consisting of 4–5 rows of linear, thick-walled cells, strongly ciliate marginal teeth that are sometimes branched and up to 7 cells long in upper fertile stem leaves and perichaetial leaves, and a much shorter leaf costa that ends just above mid-leaf in the lower leaves.  相似文献   

6.
Steinernema weiseri n. sp. is described from a roadside with apple trees near Ceské Budejovice, Czech Republic. The species is also widely distributed in Germany and Slovakia, from where it had previously been reported as Steinernema spec. F. The British Steinernema sp. D1 is considered conspecific with S. weiseri n. sp. Males of the new species are mainly characterised by light brown, slightly curved spicules with a long manubrium and the presence of a short tail mucron in the second generation. Third-stage infective juveniles are characterised by a `medium size' body and tail length, short hyaline tail portion (mostly around 1/3 of tail length), the excretory pore situated in the mid-pharynx region, lip region slightly offset, angular and flattened, and the lateral field having nine equally developed lines separated by eight distinct ridges. S. weiseri n. sp. is most similar to S. feltiae, with which it did not hybridise. RFLP analysis of the ITS region of the rDNA repeat shows S. weiseri n. sp. to be distinct from 50 other Steinernema species and isolates. The new species was found in a wide range of habitats and is readily maintained on Galleria mellonella larvae.  相似文献   

7.
During a recent soil sample survey in Heidelberg at the Suikerbosrand Nature Reserve near Johannesburg in South Africa, a new entomopathogenic nematode species, collected from the grassland was discovered. Oscheius basothovii was isolated from soil samples using the Galleria mellonella bait method. Amplification and Sanger sequencing of the 18S ribosomal DNA placed the nematode in genus Oscheius. Morphological studies with light and scanning electron microscopy confirmed its anatomical affinities with the genus. The new species is characterised by various traits including its original 18S rDNA sequence, six lips, and amphidelphic reproduction. Males were characterised by the presence of spicules towards their posterior end and short blunt tails. Females had a body with irregular ridges, a vulva opening, and long pointed tails. The infective juveniles of this new species are able to invade Galleria mellonela and Tenebrio molitor larvae and cause mortality within 24–72?h after inoculation under laboratory conditions.  相似文献   

8.
Saussurea xinjiangensis Y. S. Chen, a new species from Xinjiang, China, is described and illustrated. It was first found during a field expedition by the author in 2014. It belongs to S. subgen. Saussurea sect. Laguranthera because its root and caudex split fibrously and it has numerous capitula in a corymbiform synflorescence. The new species is similar to S. mucronulata in its habit, strongly fibrous rootstock and caudex, sessile linear leaves and capitula shortly pedunculated in a corymbiform synflorescence. However, it differs from S. mucronulata by its usually branched stems (versus usually simple or apically few-branched), lower leaf blade 8–12 cm long and 0.5–1.8 cm wide (versus 3–5 cm long and 0.2–0.5 cm wide), leaves abaxially sparsely arachnoid tomentose (versus densely arachnoid tomentose), phyllary white arachnoid tomentose and green to brown (versus glabrous and blackish purple).  相似文献   

9.
A new species of Rubiaceae, Spiradiclis glabra, is described and illustrated from China. The species is most similar to S. fusca, but differs by having 5–7 pairs of adaxially unconspicuous secondary veins in the leaves, stipules 2–5 mm long, calyx lobes ovate‐triangular, corollas slightly purple–reddish, tubes 13–15 mm long, inside with a pubescent ring of long hairs at the throat, and stamens near the base in long‐styled form. The conservation status of this new species was assessed as ‘Vulnerable’ (VU) according to IUCN.  相似文献   

10.
Two Sargassum species (S. baccularia and S. polycystum) collected from Teluk Kemang and Cape Rachado, Port Dickson, Negeri Sembilan, Malaysia, which are alike in morphology except for the rhizoidal system and vesicles, were characterised using random amplified polymorphism DNA (RAPD). The genomic DNA of both species was isolated from the leaves using a modified CTAB method. Four random primers, that is, OPA2, OPA3, OPA4 and OPA13, successfully amplified the DNA. The polymorphisms generated by these four primers were analysed using the Dice Coefficient of Similarity and cluster analysis was carried out using GelCompar II Version 2.0 (Applied Maths, Kortrijk, Belgium) based on UPGMA. DNA analysis showed that three primers were able to differentiate the two species. Morphological analysis using Principal Components Analysis (PCA) and discriminant function analysis supported the molecular data. Both species are characterised by heavily muricate main branches, oblong-lanceolate leaves with dentate margins and discoid holdfasts and spherical vesicles; both are dioecious. The only difference is that S. polycystum has secondary holdfasts transformed into stolons. This last characteristic is therefore a very important criterion and may contribute to the difference shown by DNA analysis.  相似文献   

11.
A new species of Aerobryum Dozy & Molk. (Brachytheciaceae), A. brevicuspis S.He from Lao Cai Province, northern Vietnam is described and illustrated. The new species resembles epiphytic A. speciosum Dozy & Molk. in the presence of pendent, sparsely branched stems, similar shape of leaves and areolation, but differs by its apiculate to cuspidate leaf apices, a single, faint or sometimes double costae in branch leaves, rather differentiated alar cells, the presence of a central strand in the stems, and numerous clustered axillary hairs that are often 5-8(-10) cells long.  相似文献   

12.
A new species of Capparaceae, Capparis longgangensis X. L. Mo & X. S. Lee ex Y. S. Huang is described and illustrated. The new species is similar to C. micracantha DC., but differs from it by the following characteristics: twigs, gynophore, outer surface of sepals and persistent style densely yellow–brown pannose, leaves densely yellow–brown pannose on both surfaces when young, abaxial surface thinly yellow–brown pannose when mature, petal thinly yellow–brown pannose, fruit 5–7 mm long, ca 6 mm in diameter, apical persistent style 3–4 mm long.  相似文献   

13.
《Journal of bryology》2013,35(1):56-68
Abstract

A new species of Pseudocrossidium R.S.Williams, P. exiguum M.J.Cano &; J.A.Jiménez, is described from South America (Argentina, Brazil and Peru). The species is distinguished morphologically by its lingulate to oblong-ovate leaves, leaf marginal cells not or scarcely differentiated from inner, costa ending below apex or percurrent, and semicircular to elliptical in cross-section with two guide cells, scarcely differentiated perichaetial leaves and peristome of short and straight teeth. Drawings and light microscope photographs of the new species are provided. The principal distinctive characters that separate it from the nearest species of Pseudocrossidium and related genera are discussed.  相似文献   

14.
The new species Spiradiclis jingxiensis R. J. Wang is described here. It is similar to S. danxiashanensis with respect to its prostrate habit, small leaves, and terminal inflorescence with 1–3 salverform flowers, but is readily distinguished by pinkish flowers, and included stamens and stigmas in long‐ and short‐styled flowers. The conservation status of the new species was preliminarily assessed as ‘EN’ according to IUCN categories and criteria.  相似文献   

15.
Onosma maculata Ranjbar & Almasi, a new Boraginaceae species endemic to Iran, is described and illustrated. The new species belongs to Onosma sect. Onosma subsect. Onosma. It is closely related to O. nervosa Riedl, but is easily distinguished by its spotted stem and peduncle (vs no spots), leaves 14–23 cm long (vs leaves 4–12 cm long), pedicel 5–15 mm long (vs pedicel 3–5 mm long), higher density of hairs, and glabrous nutlet (vs villous). Moreover, meiotic chromosome number and behavior were studied in two populations of the new species and it was found to be diploid with 2n = 2x = 16.  相似文献   

16.
New palm leaves from the Oligocene Ningming Formation are placed into the morphogenus Sabalites because of their costapalmate leaf shape. Four taxa are described on the basis of leaf compressions with cuticular structure. S. guanxiensis sp. nov. is characterised by hypostomatic leaf blades with a stout costa and a symmetrical base. Sabalites cf. asymmetricus has amphistomatic leaf blades with a long, delicate costa and an asymmetrical base. Sabalites sp. 1 has amphistomatic leaf blades with a long, massive costa and wide segments. Sabalites sp. 2 is characterized by hypostomatic leaf blades with a prominent costa and an asymmetrical base. The four new palm taxa expand our understanding of the floristic elements and features of the Oligocene Ningming flora. Together with the other three palm taxa that were previously reported from the Ningming Formation, our material indicates that the Oligocene Ningming flora had a rich diversity of costapalmate palms. The relatively high species diversity of palms and other plants corroborate that the Oligocene Ningming flora represents a warm and humid climate.  相似文献   

17.
A new species of Dryophthorus and two new species of Stenommatus (Coleoptera: Dryophthoridae) are described from Dominican amber. Dryophthorus microtremus n. sp. is characterised by monochrome dorsal scales, nearly parallel sides of the pronotum, wide elytral intervals and the elytral apex only slightly narrowed. Stenommatus tanyrhinus n. sp. is characterised by an elongate rostrum 4.5 times as long as wide in the middle. S. leptorhinus is characterised by small body size, a thin rostrum 3.0 times as long as wide in the middle, wide striae and a narrow prosternal process. This brings the total number of species of Dryophthorini in Dominican amber to five, which is more than half the number of extant species.http://www.zoobank.org/urn:lsid:zoobank.org:pub:4329D0DA-57BD-4CEA-9464-ABD5D1577FC9  相似文献   

18.
A new crystal compound 2,5-diacetoxy-2-benzyl-4,4,6,6-tetramethyl-1,3-cyclohexanedione was isolated from the leaves of Syzygium lineare. The insecticidal activity of the compound was assessed against fourth instar larvae of Spodoptera litura. Its activity was better than the positive control azadirachtin. The compound was responsible for growth inhibition on S. litura. It induced larval, pupal and adult deformities even at low concentration. The compound may be useful as a botanical pesticide.  相似文献   

19.
《Journal of bryology》2013,35(4):387-400
Abstract

Lejeunea brenanii sp. nov. and Microlejeunea ankasica sp. nov. are described. Lejeunea autoica Schuster and Pycnolejeunea contigua (Nees) Grolle are described and recorded as new to Africa. Lejeunea longirostris (Steph.) E.W. Jones, nom. inval., is a synonym of L. grossecristata (Steph.) E.W. Jones. Critical notes and/or new localities are provided for Colura digitalis (Mitt.) Steph., C. dusenii Steph., C. humbertii S. Jovet-Ast, C. sp. ad inornata Jovet-Ast, Marchesinia moelleriana Pearson.  相似文献   

20.
Two new species of Centaurea L. sect. Cynaroides Boiss. ex Walp. (Asteraceae), C. shahuensis Ranjbar and Negaresh and C. ravansarensis Ranjbar and Negaresh are described and illustrated from Kermanshah Province, west Iran. They are closely related to C. regia Boiss. subsp. regia. However, C. shahuensis differs from it by median stem leaves broadly oblanceolate or subpandurate, phyllaries densely lanate‐tomentose, appendages small, concealing a minor part of phyllaries, and also median appendage margin entire sometimes with 1–2 cilia, 1.2–3.0 mm long on each side. Centaurea ravansarensis is distinguished by upper stem leaves loosely arachnoid, phyllaries loosely floccose‐tomentose, inner appendages deep brown to blackish, and spine 4.5–6.0 mm long. Habitat, conservation status and the geographical distribution of the new species are given.  相似文献   

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