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1.
Yeon-Shim  Keum  Lee  In Kyu 《Hydrobiologia》1993,260(1):97-104
The vegetative and reproductive morphology of two epiphytic Herpochondria species, H. corallinae (Martens) Falkenberg (the type species) and H. elegans (Okamura) Itono from Korea were investigated. They are bilaterally compressed and alternate-distichously branched, and lateral branches are produced by oblique divisions of the apical cell. Procarps are restricted to the first periaxial cell of the branches. Spermatangial mother cells produce one or two spermatangia. H. corallinae forms tetrasporangia on six periaxial cells, whereas H. elegans has them on only the two lateral periaxial cells. The prostrate habit, the production of six periaxial cells in opposite pairs, and tetrasporangial stichidia are confirmed as diagnostic characters of the genus Herpochondria.  相似文献   

2.
Observations are made on the occurrence and distribution of the red algal genus Hypoglossum Kützing (Delesseriaceae, Ceramiales) in the tropical western Atlantic. In addition to the type of the genus, H. hypoglossoides (Stackh.) Coll. & Herv., three other species are reported: H. anomalum sp. nov., H. involvens (Harv.) J. Ag., and H. tenuifolium (Harv.) J. Ag. A key is presented to distinguish these four species. The newly described species, H. anomalum, is like other species in the genus in that its branches arise endogenously from the primary axial row but it is unique in that the branches emerge from the parent blade at some point between the midline and the margin of the blade. The new species is reported from Puerto Rico and Florida.  相似文献   

3.
Three species of Antithamnion Naegeli were previously known from Natal, all reported since 1984. A more thorough collection of the flora in recent months has revealed that there are nine species in Natal, four of which are newly described. Vegetative characteristics are emphasized in this study of the taxonomy of Antithamnion, the most important being (1) size of axial cells, (2) form of whorl-branchlets, (3) size of whorl-branchlet basal cells, (4) size and shape of whorl-branchlet terminal cells, (5) size and position of gland cells, (6) primary or secondary derivation of indeterminate lateral branches, and (7) the relationship of primary indeterminate branches, if present, to normal arrangement of whorl-branchlets. Two closely related species, A. diminuatum Wollaston and A. eliseae sp. nov. have been grown in laboratory culture allowing for testing of stability and reliability of vegetative characteristics for use in taxonomic studies. Conclusions are that these criteria can be effectively used for these purposes. In addition to A. eliseae, A. nematocladellum, A. pterocladellum and A. adenocladellum also are described as new species. A tropical species previously known from the Caribbean and Red Seas, A. lherminieri Nasr, a species previously recorded from Japan, A. secundum Itono, a species previously known from California and Japan, A hubbsii Dawson, and two species from Australia, A. diminuatum Wollaston and A. divergens (J. Agardh) J. Agardh, are also described from Natal.  相似文献   

4.
Antithamnion makroklonion sp. nov. is described from Elat, Gulf of Aqaba (Gulf of Elat) in the Red Sea, where vegetative, spermatangial, and tetrasporangial specimens were found growing in the upper sublittoral zone. The new alga belongs to a group of Antithamnion species characterized by distichous-alternate ramification of branches, sessile tetrasporangia, and decussately arranged laterals along the bearing axis. It shows a unique combination of distinctive features, including the proximal development of gland cells on elongate branchlets that overtop the parent branch. In addition to the characteristic position, and in contrast to congeners, gland cells of A. makroklonion often have a large and prominent cytoplasmic band and one or two vacuoles. Morphological features of A. makroklonion and eight related species are tabulated and the characteristics of the new species are discussed.  相似文献   

5.
Rubia austrozhejiangensis Z. P. Lei, Y. Y. Zhou & R. W. Wang, a new species of Rubiaceae from China, is described and illustrated. The new species is similar to R. ovatifolia Z. Ying Zhang and R. argyi (H. Lév. & Vaniot) H. Hara ex Lauener, but differs from the former in having stems and branches cylindrical, not quadrate‐angled, long‐ovate to ovate‐lanceolate leaf blades, many‐flowered inflorescence, and smaller mericarps, 3–4 mm in diameter. In R. ovatifolia, stems and branches are quadrate‐angled, leaf blades ovate, ovate‐cordate to rounded cordate, and the inflorescences are sparsely flowered. Compared to R. argyi, the new species has cylindrical, not quadrate‐angled stems and branches, leaf blades that are long‐ovate to ovate‐lanceolate, 3–5‐veined, and slightly reflexed corolla lobes. In R. argyi, stems and branches are quadrate‐angled or winged, the corolla lobes are spreading, and the mericarps are 5–7 mm in diameter.  相似文献   

6.
Three species of Antithamnion Naegeli were previously known from Natal, all reported since 1984. A more thorough collection of the flora in recent months has revealed that there are nine species in Natal, four of which are newly described. Vegetative characteristics are emphasized in this study of the taxonomy of Antithamnion, the most important being (1) size of axial cells, (2) form of whorl-branchlets, (3) size of whorl-branchlet basal cells, (4) size and shape of whorl-branchlet terminal cells, (5) size and position of gland cells, (6) primary or secondary derivation of indeterminate lateral branches, and (7) the relationship of primary indeterminate branches, if present, to normal arrangement of whorl-branchlets. Two closely related species, A. diminuatum Wollaston and A. eliseae sp. nov. have been grown in laboratory culture allowing for testing of stability and reliability of vegetative characteristics for use in taxonomic studies. Conclusions are that these criteria can be effectively used for these purposes. In addition to A. eliseae, A. nematocladellum, A. pterocladellum and A. adenocladellum also are described as new species. A tropical species previously known from the Caribbean and Red Seas, A. Iherminieri Nasr, a species previously recorded from Japan, A. secundum Itono, a species previously known from California and Japan, A hubbsii Dawson, and two species from Australia, A. diminuatum Wollaston and A. divergens (J. Agardh) J. Agardh, are also described from Natal.  相似文献   

7.
A new species of Dudresnaya is described from Puerto Rico and Georgia. Gametophytes have cylindrical axes, exserted apical cells, rectangular to hexagonal crystals in the axial cells, ellipsoidal outer assimilatory cells, spermatangial mother cells which are terminal or subterminal cells of the subdichotomously branched outer assimilatory branches and auxiliary cells which are indistinguishable in appearance from adjacent, large, deeply staining cells of the auxiliary cell branch. Tetrasporophytes are unknown.  相似文献   

8.
In the course of a revision of species of Haemonchus Cobb, 1898 (Nematoda), commonly referred to as large stomach worms and significant pathogens of ruminants, a new species was discovered in the grey rhebuck Pelea capreolus, and the bontebok Damaliscus pygarthus, in South Africa. The new species, Haemonchus horaki, was previously reported as a long-spicule form of H. contortus (Rudolphi, 1803) Ransom, 1911. The new species, compared with H. contortus, can be distinguished by significantly longer spicules (555-615 microm vs. 383-475 microm); a synlophe with fewer ridges (26 vs. 30 in the region of the posterior part of the esophagus) that extend more posteriorly (within 1 mm of the copulatory bursa in males and postvulvar in females, vs. 2/3 to 3/4 of prebursal and prevulvar lengths); and an asymmetrical dorsal lobe with a long dorsal ray divided for more than half of its length, forming 2 branches of unequal length (vs. a dorsal ray divided for less than half of its length and forming 2 equal branches in H. contortus).  相似文献   

9.
10.
Two new species of Heligmonellidae from Madagascar are described, Heligmonina madagascariensis n. sp. in Nesomys rufus and Heligmonina tanala n. sp. in Eliurus tanala. Both species belong to the Heligmonina species with a pattern of type 1-3-1 for the right lobe of the caudal bursa and 1-4 for the left lobe. In H. madagascariensis, H. dupuisi (Desset, 1964) and H. praomyos Baylis, 1928, left ray 6 arises before ray 3 from the common trunk to rays 3 to 6 while in H. tanala and the other species, it arises at the same level. H. madagascariensis is differentiated from H. dupuisi and H. praomyos by the symmetry of the branches of the dorsal ray. H. tanala is differentiated from H. malacomys Sakka & Durette-Desset, 1988, the closely related species by a different pattern of the cuticular ridges at mid-body, by the sharpness of the tips of the spicules and by the ratio of the length of the spicules on the length of the body (6.9, 8.8% versus 25-27.8%). Heligmonina chippauxi (Desset, 1964) a parasite of Oenomys hypoxanthus from the Republic of Central Africa is considered a valid species.  相似文献   

11.
A new red alga, Dasya enomotoi, is described from Japan. This species is characterized by having a large thallus consisting of an elongated axis and many, radially arranged, polysiphonous branches both of which are heavily corticated and densely covered with numerous, soft monosiphonous filaments. It is distinguished from several similar species by the combination of the following: (i) indistinct pericentral cells in transverse sections except near the apices, (ii) the presence of enlarged, inner cortical cells, (iii) radially arranged adventitious monosiphonous filaments, (iv) three‐celled carpogonial branches, (v) six (sometimes five) tetrasporangia in each fertile segment of the stichidia, and (vi) three tetrasporangial cover cells that are not elongated longitudinally and usually not divided transversely. This species may have been identified as D. villosa Harvey by previous investigators in Japan.  相似文献   

12.
Saprolegnia oliviae sp. nov. is described from litter (floating dead twigs, leaves and roots) in the Olivia River, Ushuaia Department, Tierra del Fuego Province (Argentina). The new species is illustrated and compared with other species of the genus. Distinguishing characteristics of S. oliviae are the production of smooth oogonia (with some lateral or terminal projections) and the absence of antheridial branches on the majority of the oogonia, but when present, they are mostly diclinous, at times oogonia are supplied with androgynous and monoclinous antheridial branches. The oogonial stalks are predominantly short and straight or long and bent, curved or many times coiled; oospores are distinctive subcentric, (1-) 15-50 (-70) per oogonium. Morphological details of the new species and its comparison with other described species are discussed here.  相似文献   

13.
Predation by Halmus chalybeus (steelblue ladybird) on two species of wax scale was studied on citrus orchards in Northland, New Zealand. Field experiments using an exclusion technique of enclosing citrus branches in bags, found that larval and adult H. chalybeus preyed on first and second instars of both Ceroplastes destructor (white wax scale) and C. sinensis (Chinese wax scale), but not third instar C. destructor. Third instar C. sinensis and adults of both species were not tested but are rarely, if ever, attacked by H. chalybeus. The sampling of scale and ladybird populations and field experiments showed that few scales of either species survived past the second instar stage where H. chalybeus was numerous. The feeding rate of H. chalybeus on settled first and second instar scales was estimated inside bagged branches. Adults consumed on average 15.6 C. destructor and 13.3 C. sinensis per day per ladybird, while larvae ate 9.7 C. destructor per day. These feeding rates accounted for the experimental reduction of scale populations. H. chalybeus is a useful natural enemy for the control of C. destructor and C. sinensis when its activity is not disrupted by pesticides.  相似文献   

14.
The present paper includes a morphological, ecological and biological updating of the three gorgonian associated species of Haplosyllis (Polychaeta, Syllidae) known to date: H. chamaeleon (symbiont with Paramuricea clavata in the Mediterranean), H. anthogorgicola (symbiont with Anthogorgia bocki in the Japanese seas) and H. villogorgicola , a new species living symbiotically with Villogorgia bebrycoides which is only known from Tenerife (Canary Islands, Eastern Central Atlantic). The new species is described on the basis of ecological, morphological, morphometric and statistical analysis of relevant characteristics. Each host colony harboured about 15 pale-yellowish worms, whose cryptic colouration mimicked that of the host. They occurred either on the host branches or partly hidden inside cavities formed by the fusion of two branches. The new species is characterized by the presence of simple chaetae with clearly bidentate tips all along the body, the presence of gland pore aggregates distributed in two lateral rows and two ventral patches on each palp and the absence of ciliary tufts on the pharyngeal papillae. H. villogorgicola sp. nov. is closely related to H. chamaeleon . Thus, it is compared with two populations of this species collected in the north-west and south-west Mediterranean. Stolons of H. chamaeleon are re-described as tetracerous and a peculiar posterior end regeneration process occurring in adult worms during the stolon formation is described. H. anthogorgicola is also re-described, with particular emphasis on its appendage and chaetal arrangements. The main features of the three associations are discussed in light of the current knowledge on symbiotic polychaetes, particularly cnidarian-associated syllids.  © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 77 , 455–477.  相似文献   

15.
Franti?ek Hindák 《Biologia》2012,67(6):1075-1079
The formation of hormogonia in the nostocalean cyanophytes/cyanobacteria Hapalosiphon fontinalis (C. Agardh) Bornet and Fischerella sp. was studied in natural populations collected from the Klin peatbog, northern Slovakia. Hormogonia were produced terminally in lateral branches of filaments (both species), or also directly on the main branches (Fischerella sp.). In contrast to vegetative filaments, hormogonia were not ramified, lacked heterocytes, were embedded in mucilaginous envelopes, were able to move, and their cells contained aerotopes. They were released by gliding through an opening in the sheath at the end of lateral branches of filaments. Released hormogonia of H. fontinalis were solitary or agglomerated into common fascicles morphologically resembling planktic colonies of Aphanizomenon flos-aquae (L.) Ralfs ex Bornet et Flahault or Dolichospermum affine (Lemmermann) Wacklin, Hoffmann et Komárek (syn. Anabaena affinis Lemmermann). Occasionally, lateral or sessile Nostochopsis-like heterocytes and apical spherical monocytes were formed on the main filaments. Hormogonia of Fischerella sp. were formed not only in apical part of lateral trichomes, but also directly on the main trichomes. Their cells were markedly larger than the vegetative cells and possessed well-developed aerotopes. Released hormogonia remained solitary, and were not agglomerated into fascicles. Apical hormogonia were released by gliding through an opening in the sheath at the end of lateral branches of filaments, and basal hormogonia were released by breaking off the main axis. In contrast to filaments of H. fontinalis which were very common and represented the dominant species of the cyanophyte communities in the locality, filaments of Fischerella sp. were observed only in one sample and for a limited period. This is the first record of a representative of the genus Fischerella in Slovakia.  相似文献   

16.
Two new species of Schizostachyum Nees (Poaceae: Bambusoideae): S. yalyense N. H. Xia, V. T. Tran et H. N. Nguyen and Schizostachyum ninhthuanense N. H. Xia, V. T. Tran et H. N. Nguyen (Poaceae: Bambusoideae) are described and illustrated from Vietnam. Schizostachyum yalyense is similar to S. lima (Blanco) Merrill, but differs by culm sheaths with a concave apex 4–5 cm wide and 1.0–1.5 cm deep, pseudospikelets clustered on the wholly leafless flowering branches, possession of 2 bracts and lodicules. Schizostachyum ninhthuanense is related to S. hainanense Merrill ex McClure, but differs by culm sheaths covered with white hairs and having white–brown hairs at the apex, ligule margin densely pale‐ciliate, pseudospikelets clustered on wholly leafless flowering branches, presence of 3 lodicules, two stigmas apically on the style and the third stigma branching off from one of the two other stigmas.  相似文献   

17.
东亚特有属——小勾儿茶属的研究   总被引:2,自引:0,他引:2  
钱宏 《植物研究》1988,8(4):119-128
本文对东亚特有属——鼠李科小勾儿茶属(Berchemiella)进行了比较系统地研究, 对该属的建属历史, 形态特征、木材解剖、分类及分布进行了论述。根据该属的木材构造和花粉形态等, 作者赞同中井猛之进将Berchemiella独立为属的观点。该属共有3种1变种, 在我国有2种1变种。毛柄小勾儿茶(B.wilsonii var.pubipetiolata H.Qian, 新变种)为首次描述。  相似文献   

18.
The modification of core histone proteins in mouse 10T1/2 cells and human lung epitheloid (A549) cells by B(a)PDE in vivo and in vitro was found to be similar. Only histones H2A and H3 were extensively modified. Also other proteins, possibly A24 protein and the minor histone H1 species seem to be binding relatively high levels of this ultimate carcinogen. Butyrate treatment which causes hyperacetylation of the core histones, did not change the specificity of B(a)PDE binding to core histones, nor did it affect the initial level of DNA modification. The acetylated species of histone H3 were all accessible to B(a)PDE, suggesting that these epsilon-amino-groups of the lysine residues are not the targets of the B(a)PDE. The rate of removal of B(a)P-DNA adducts was not affected by butyrate treatment in either normal human or XP fibroblasts. Furthermore the B(a)P-core histones were not preferentially removed from normal human fibroblast chromatin during a 24 h post-treatment incubation.  相似文献   

19.
This is the first comparative study of floral structure of the recently established new family Picrodendraceae (part of Euphorbiaceae s.l.) in Malpighiales. Nine species of eight (out of ca. 28) genera were studied. Female flowers are mainly completely trimerous, and in such flowers the perianth consists of one or two whorls of sepals. A floral disc (which probably functions as a nectary) is mostly present. The free parts of the carpels are simple (unbranched) in all ten species studied. Each carpel contains two crassinucellar, anatropous or hemitropous, epitropous (antitropous) ovules, which are covered by a large obturator. The inner integument is thicker than the outer (equally thick in two species studied), and commonly both integuments form the micropyle. In mature ovules the vascular bundle commonly branches in the chalaza, with the branches extending to the base of the inner integument but not entering it. A nucellar cap and, less often, a nucellar beak is formed. Floral structure supports the close relationship of Picrodendraceae with Phyllanthaceae and Euphorbiaceae s.str. within Malpighiales, as suggested (but not yet strongly supported) by some recent published molecular analyses. These three families share a unique combination of characters, including (1) unisexual, apetalous trimerous flowers, (2) crassinucellar ovules with a nucellar beak, (3) a large obturator, and (4) explosive fruits with carunculate seeds.  相似文献   

20.
Four new species of blackflies (Diptera: Simuliidae) are described. Helodon rezidentsii Yankovsky, sp. n., Khabarovsk Territory, differs from all known species of the genus with morphology of eyes consisting only of microommatidii in male; from related species H. kamtshaticus (Rubzov, 1940) with large triangular posteromedial lobes of branches of genital fork in female; with number of rays of primary fan of premandibles (20-22, when in H. kamtshaticus 30-32) in larva. Helodon submulticaulis Yankovsky, sp. n., Transbaikalia, differs from related species H. multicaulis (Popov, 1968) with number of rays of primary fan of mandibles (36-40, when in H. multicaulis 26-28), narrow anterior branches of anal sclerite, number of rows of hooks in posterior attachment organ (88-92, when in H. multicaulis 78-80) in larva; with morphology of respiratory organ, consisting of 5-8 lobes bearing 40-60 tune filaments (in H. multicaulis 3-4 lobes bearing more than 150 filaments) in pupa. Sch. samarkandica Yankovsky, sp. n., Uzbekistan, differs from related species Sch. pseudopusilla Rubzov, 1956 with 3 (not 2 as in Sch. pseudopusilla) hooks in parameres, bifurcated lateral branches of X sternite, long projection of gonostyles in male. Schoenbaueria ivdelensis Yankovsky, sp. n., Middle Ural, differs from related species Sch. rangiferina (Rubzov, 1956) with prolonged gonostyles bearing narrow projection in male; with number of rays of secondary fan of premandibles (20-28, when in Sch. rangiferina 44-48), deep ventral groove of cephalic capsule, number of rows of hooks in posterior attachment organ (80-82, when in Sch. rangiferina 70-72) in larva; with morphology of respiratory organ (very long stems of 2 and 3 pairs of filaments) in pupa.  相似文献   

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