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1.
Dioon argenteum sp. nov. (Zamiaceae) is described from northern Oaxaca, México. Flat leaves, and persistently tomentose, slightly imbricate leaflets with marginal prickles characterize this species. The specific epithet argenteum was chosen to describe the silver appearance of the persistent tomentum covering the new leaves. D. argenteum appears to have affinities with D. purpusii and D. califanoi.   © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 471–476.  相似文献   

2.
Ceratozamia becerrae sp. nov. is described and illustrated. This species from Tabasco and Chiapas has affinity with C. miqueliana H. Wendl. from Veracruz and Chiapas, but differs in morphology and habit of leaves, leaflets, male and female strobili and trunk. Ceratozamia becerrae is considered part of the C. miqueliana species complex that includes C. miqueliana, C. euryphyllidia Vázq.Torres, Sabato & Stevenson and C. zoquorum Pérez-Farrera, Vovides & Iglesias. The geographical range of this species complex is southern Veracruz, Tabasco and northern Chiapas in tropical rain forests.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 123–128.  相似文献   

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Phylogenetic relationships between Encephalartos altensteinii Lehmann, E. arenarius R.A. Dyer, E. horridus (Jacquin) Lehmann, E. latifrons Lehmann, E. lehmannii Lehmann, E. longifolius (Jacquin) Lehmann, E. princeps R.A. Dyer and E. trispinosus (Hooker) R.A. Dyer were studied, using E. ferox Bertoloni f. as outgroup. Three continuous and one discontinuous buffer systems were used and gene products of 14 enzyme coding loci were examined by horizontal starch gel-electrophoresis. Genetic variation was studied in a cultivated population of E. lehmannii and the average heterozygosity value for this population is 13.5%, which falls within the range reported for other cycad species. Fixed allele differences between the species studied was not found at any of the loci studied, which suggest that these species are closely related. DNA sequence analysis of rbcL and ITS 1 & 2 genes (1428 and 895 basepairs, respectively) confirmed the close genetic relationships between these taxa. According to ITS and rbcL sequences E. altensteinii and E. princeps are sibling taxa which form a sister group to E. arenarius, E. horridus, E. latifrons, E. lehmannii, E. longifolius, and E. trispinosus. The genetic distances between both groups were 0.12-0.47% for ITS and 0.08-0.16% for rbcL DNA. The results indicate recent (probably pleistocenic) speciation for this group of cycads, and the relationships are discussed with reference to affinities based on morphology and distribution.  相似文献   

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Ten microsatellite loci isolated from Zamia integrifolia are described. All 10 are polymorphic, with three to 10 alleles across 36 members of a single population from South Florida. Heterozygosities ranged from 0.139 to 0.889. Two loci depart significantly from Hardy–Weinberg equilibrium, and exhibit heterozygote deficiency. One locus pair exhibits significant linkage disequilibrium. The primers have also successfully amplified loci from Zamia portoricensis and Zamia ambliphyllidia. These loci will be utilized for population studies in the Caribbean Zamia pumila complex.  相似文献   

9.
Paracyclops longispina n. sp. and Paracyclops altissimus n. sp. are described. New characters derived from detailed examination of body and limb ornamentation are used to differentiate them from other Paracyclops species. Paracyclops longispina n. sp. resembles Paracyclops fimbriatus (Fischer, 1853) and Paracyclops imminutus Kiefer, 1929. It differs from the former by the presence of a well-developed spinular row near the base of the inner setae on the antennal coxobasis in both sexes, and from the latter in the structure of the seminal receptacle and the position of the mid-distal spinular row on the posterior surface of the coxa of leg 1. Paracyclops altissimus n. sp. can be distinguished from other members of genus mainly by the structure of the seminal receptacle and leg 5. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

10.
A new species of Cryptolepis is described from Kenya and Tanzania. It is a tropical forest climber and its unique second corona whorl of deeply cleft lobes distinguishes it from all other Cryptolepis species.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 343–346.  相似文献   

11.
Ceratozamia zoquorum sp. nov. from the northern mountains of Chiapas, Mexico, is described and illustrated. It has affinities with C. miqueliana Wendl. from Veracruz, but differs in leaf, male female cone and trunk morphology.  相似文献   

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Ceratozamia norstogii sp. nov. from Chiapas, Mexico is described. This species is distinct from all others in the genus in that it has a straight rachis with very narrow leaflets (3–10 mm wide) which are strongly curved and almost round in cross section when dried. It is known only from Chiapas, Mexico and in cultivation.  相似文献   

14.
As a result of recent fieldwork in north-east Morocco, a new woody Malvaceae species, Lavatera valdesii Molero & J.M. Monts., is described here. The morphological characters that link it to other species in Sect. Olbia (Medik.) DC. are discussed, as are those traditionally used in defining the species that make up this section. A recently described species of this group, Lavatera plazzae Atzei, is established here as a synonym of L. stenopetala Coss. & Durieu ex Batt., a species previously considered as an endemic of east Algeria. On the basis of morphological characters, we propose the exclusion of both L. thuringiaca and L. cashmiriana Cambess. from Sect. Olbia.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 445–454.  相似文献   

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Tropodiaptomus turkanae sp. nov. is described from Lake Turkana (formerly Lake Rudolph), Kenya. After years of confusion with T. banforanus , the identity of this taxon as an endemic of Lake Turkana is established. The species is described, and its relationship with other Tropodiaptomus species discussed.  相似文献   

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The examination of material representing one of Lake Tanganyika's six previously recognized endemic catfish lineages, has revealed the presence of an additional genus of clariid, described here as Pseudotanganikallabes new genus. This genus is represented by a single species, Pseudotanganikallabes prognatha sp. nov., which is distinguished from all other clariids by its lack of an infraorbital series, the presence of multiple osseous connections between the swim bladder capsules and elements of the neurocranium, the absence of an ethmoid notch, the presence of a very large, egg‐shaped occipital fontanelle and the extension of the lower lip beyond the margin of the upper jaw. A combination of additional external and molecular characters serves to further distinguish this taxon from all currently recognized clariid species. Phylogenetic analysis of mitochondrial (cytb) and nuclear (18S‐ITS1‐5.8S‐ITS2‐28S) sequence data supports the creation of a new genus for this species, as it appears to represent an independent, monophyletic lineage within the family Clariidae.  相似文献   

19.
Gazza squamiventralis sp. nov. is described as the fifth species of the genus, based on the holotype and eight paratypes, 42–96 mm in standard length, collected along the east coast of Africa, from Kenya to Mozambique. The species is similar to other congeners in general appearance, differing clearly from them in having the ventrolateral surface of the body scaled anterior to a line from the pectoral fin base to the pelvic fin origin (vs naked) and a smooth supraorbital ridge (vs finely serrated). Additionally, the species differs from G. dentex, G. rhombea, and G. achlamys in having the dorsolateral surface of the body scaled anterior to a vertical through the tip of the posterior branch of the supratemporal canal (vs corresponding region naked), and from G. minuta in having the first dorsal fin pterygiophore narrowly expanded anteriorly, with a concave margin (vs broadly expanded, with a convex or linear margin), and a short antrorse extension of the first anal fin pterygiophore (vs long). A key to the five species of the genus Gazza is provided. Received: May 30, 2000 / Revised: September 16, 2000 / Accepted: January 16, 2001  相似文献   

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RAHMAN, M. A. & WILCOCK, C. C, 1992. A new species of Periploca (Periplocaceae) from Bangladesh. A new species of Periploca is described from Bangladesh. This is the only representative of the genus occurring in the flora of Bangladesh. It resembles P. graeca but may be distinguished by having shorter peduncles, glabrous calyx lobes, hairy coronal scales, broader and horizontally spreading follicles.  相似文献   

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