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1.
Psidium acutangulum has been previously understood as a widespread and variable species. Here, it is proposed that populations east of the Andes should be divided into two species: P. acutangulum and P. acidum based on characters of the leaves, anthers, fruits and seeds. The new combination Psidium acidum is made here and the species is described, illustrated and contrasted with P. acutangulum and P. friedrichsthalianum. Psidium acutangulum as now understood remains variable and seems to be related to a mainly Amazonian group of species. Populations from western Ecuador, once thought to belong to P. acutangulum are now considered a new species.  相似文献   

2.
The metric traits of shrubs, leaves, seeds, and flower parts have been studied in 19 Siberian populations of Nitraria sibirica Pall. and N. schoberi L. According to the obtained data, N. schoberi is characterized by larger shrubs (150–179 cm in height), leaves (15–30 mm in length, 5.7–8.8 mm in width), and seeds (up to 10 mm in length) and has rather wide (~2.5 mm) corolla petals. The size of anthers exceeds that of N. sibirica 1.2–1.5 times. The height of N. sibirica shrubs does not exceed 80 cm; the length of lamina, seed, and petals of corolla is 8–10, 3.7–7.4, and ~3.5 mm, respectively; and the size of anthers is 0.5–1 mm. Irrespective of habitat conditions, the stability of metric traits typical for both species has been shown to be rather high. The only dependence on climatic parameters is observed for the height of N. sibirica, which forms creeping forms in continental regions, especially in the mountains of the Altai Republic. Vegetative organs (laminas and young shoots) of N. sibirica are always more pubescent than those of N. shoberi.  相似文献   

3.
Previous studies reported Psidium as one of the most difficult genera to delimit within the American Myrtaceae. Even though palynology has improved the taxonomy of Angiosperms, information about the usefulness of pollen morphology for taxonomic purposes in Myrtaceae remains contradictory. Here, we investigate the significance of pollen morphology for Psidium taxonomy with specific focus on its usefulness for determining species groups of taxonomic significance. Pollen traits observed by light and scanning electron microscopy were quantified and examined using cluster and ordination analyses. Average size of pollen grains was visualized by boxplots. Pollen grains of Psidium are isopolar, oblate, peroblate or oblate-spheroidal, 3-syncolporate or 4-syncolporate. The sexine ornamentation is rugulate, granulate or spinulose-granulate and differs between the mesocolpium and apocolpium. Cluster analysis revealed four distinct groups: Psidium cauliflorum (G1) and Psidium oligospermum (G3) as single-species groups; Psidium brownianum, P. oblongatum, P. ovale, P. sartorianum, P. guajava, Psidium sp. 1, Psidium sp. 2 (G2), and Psidium cattleianum, P. longipetiolatum, P. guineense, P. myrtoides (G4). Supported by ordination analysis, three traits better explained these groups: type of exine ornamentation, size of P-EV and pollen shape. The used approach efficiently distinguished related species, as well as explained species groups of taxonomic significance suggesting pollen morphology to be a significant source of information for taxonomic studies in Psidium.  相似文献   

4.
A taxonomic review of the clingfish genus Kopua (Gobiesocidae: Trachelochisminae) in Japan recognizes three species: K. japonica Moore, Hutchins and Okamoto 2012, K. vermiculata Shinohara and Katayama 2015 and K. yoko sp. nov. Kopua japonica and K. vermiculata are redescribed with revised diagnoses on the basis of 20 specimens (10.4–30.4 mm standard length; SL) and the holotype, respectively. Kopua japonica is similar to K. vermiculata in head sensory pore characters (normally single nasal and postocular canal pores). However, the former differs distinctly from the latter as follows: 6–8 (modally 7) gill rakers (vs. 4 or 6); 31–33 (33) vertebrae (vs. 35); anus slightly closer to posterior margin of disc than to anal-fin origin (vs. much closer to posterior margin of disc); snout length 5.3–8.7 (mean 7.0) % SL (vs. 9.2 % SL); disc length 21.2–24.0 (22.8) % SL (vs. 18.8 % SL); pre-dorsal- and anal-fin lengths 72.9–78.4 (75.2) and 78.1–82.8 (80.1) % SL, respectively (vs. 67.5 and 73.6 % SL); and two stripes on cheek (vs. a triangular blotch). Kopua yoko sp. nov., based on 14 specimens (17.7–28.8 mm SL) from the Pacific coast of southern Japan, Sea of Japan and the East China Sea, is characterized by the following combination of characters: 6 or 7 (modally 6) dorsal-fin rays; 4–6 (5) anal-fin rays; 21 or 22 (21) pectoral-fin rays; 4–6 (5 or 6) gill rakers; 31–33 (31) vertebrae; a single (rarely two) nasal canal pores; two lacrimal and preopercular canal pores; snout length 6.5–7.9 (mean 7.1) % SL; gill opening depth 5.8–7.1 (6.5) % SL; least interorbital width 2.0–3.7 (2.6) % SL; disc length 20.3–25.0 (23.1) % SL, disc region D without flattened papillae; caudal-peduncle depth 8.1–10.2 (9.2) % SL; anus slightly closer to posterior margin of disc than to anal-fin origin; pre-dorsal- and anal-fin lengths 71.6–77.1 (73.9) and 77.0–83.7 (80.4) % SL, respectively; post-dorsal-caudal length 12.6–15.0 (13.8) % SL; arch-shaped blotches on lateral aspect of body; and two reddish-orange stripes on cheek. Morphological changes with growth in K. japonica and K. yoko sp. nov. are also described.  相似文献   

5.
Phylloporia is a monophyletic genus within the Hymenochaetaceae as recovered by nuclear large subunit ribosomal DNA (nLSU) sequences. According to the summarization of 38 species accepted in this genus, Phylloporia is characterized by an absence of setae and the presence of abundant thick-walled, colored and tiny basidiospores, although its other morphological characters are highly diverse. Nine herbarium specimens from China, fitting the morphological concept of Phylloporia, were morphologically and phylogenetically studied in detail. The phylogeny inferred from nLSU sequences shows that the nine specimens formed three terminal lineages within the Phylloporia clade. Two lineages being composed of four specimens from Hainan and three from Guizhou were newly described as Phylloporia minutipora and P. radiata, respectively. In Phylloporia, P. minutipora is distinct by a combination of annual, sessile and imbricate basidiocarps, distinctly concentrically sulcate pileal surface with obtuse margin, angular pores of 12–15 per mm, duplex context separated by a black zone, a dimitic hyphal system, and broadly ellipsoid basidiospores of 2.5–3?×?2–2.5 μm, while P. radiata is distinct by a combination of annual, sessile and imbricate basidiocarps, faintly sulcate and radially striate pileal surface, sharp pileal margin, angular pores of 8–10 per mm, duplex context separated by a black zone, a monomitic hyphal system, and broadly ellipsoid basidiospores of 2.5–3.5?×?2–2.5 μm. The third lineage, comprising two specimens from Hainan, was morphologically determined as Phylloporia pulla. This species was recently combined to Phylloporia based on only morphological characters, and the current study for the first time generated its molecular sequences for phylogenetic reference. A key to all 40 species of Phylloporia is provided.  相似文献   

6.
The fatty acid (FA) composition of storage lipids in the seed endosperms and embryos of two pine species, Pinus sibirica and P. sylvestris, and possible biosynthetic pathways of these acids were studied by the GLC method. Linoleic acid predominated in the embryo and endosperm lipids of both P. sibirica (43.5 and 42.6%) and P. sylvestris (44.8 and 46.8%); this was evidently determined by a high expression of the gene encoding stearoyl-Δ9 acyl-lipid desaturase and the fad2 gene encoding microsomal ω6 acyl-lipid desaturase. P. sibirica lipids of the embryo and endosperm contained more oleic acid (22.0 and 24.0%, respectively) than corresponding P. sylvestris lipids (18.7 and 14%). Storage lipids of conifer seeds contain Δ5-unsaturated FAs: taxoleic (18:2Δ5,9), ephedrenic (18:2Δ5,11), pinoleenic (18:3Δ5,9,12), skiadonic (18:3Δ5,11, 14), and coniferonic (18:4Δ5,9,12,15). In the endosperm and embryos of P. sylvestris, the content of pinolenic acid was higher (22.1 and 19.6%) than in P. sibirica seeds (19.1 and 18.6%).  相似文献   

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10.
Two new species of Coltricia, C. austrosinensis and C. minima, are described from southern China on the basis of morphological characters and molecular evidence. Phylogenetic analysis based on the internal transcribed spacer (ITS) regions and nuclear large subunit (nLSU) ribosomal RNA gene regions indicated that the two new species were nested within the Coltricia clade in Hymenochaetales. Coltricia austrosinensis is characterized by centrally stipitate basidiocarps, lobed pileal margin, distinctly swollen stipe tip, cinnamon pore surface, large pores (1–3 per mm), and broadly ellipsoid basidiospores measuring 8–10?×?5.5–6.5 μm, with a distribution to date in subtropical China. Coltricia minima is characterized by tiny, centrally stipitate basidiocarps, entire pileal margin, uniform stipe, pileus bearing distinct concentric zones and pore surface dark greyish blue when fresh, small pores (3–4 per mm), narrow tramal hyphae (3.5–4 μm), and broadly ellipsoid to subglobose basidiospores measuring 6–7?×?4–5 μm, and occur in mixed tropical forests.  相似文献   

11.
Primates inhabiting human-modified habitats often complement their diets with cultivated species. Although this flexible foraging behavior reduces feeding stress in animals inhabiting small or low-quality habitats, its potential economic costs may promote negative human–nonhuman primate interactions. It is critical to assess the importance of cultivated species to primate diets, the factors influencing their exploitation, and their associated economic costs to evaluate the conservation value of cultivated species and the impact of crop feeding on human–nonhuman primate coexistence. Based on a 30-months study of three groups of brown howlers (Alouatta guariba clamitans) inhabiting <10-ha forest fragments in Rio Grande do Sul State, southern Brazil, and semistructured interviews with landowners, we assessed 1) the cultivated species used as food sources, 2) the relationship between food availability and crop feeding, and 3) the potential economic costs of crop feeding and their impact on landowner–howler coexistence. Brown howlers exploited six cultivated species as fruit or seed sources. This exploitation was concentrated on ripe fruit of Psidium guajava, Citrus reticulata, Diospyros kaki, and Eriobotrya japonica, which together accounted for up to 32% of total feeding records during some months. Availability predicted fruit consumption for three of these species. The overall availability of cultivated fruit also predicted its consumption, whereas overall wild fruit availability did not. Despite potential economic costs of crop feeding (US$320–US$1141 per year), landowners reported no conflict with howlers arising from their behavior, an amicable response that supports the conservation value of cultivated plants in different landscape elements of the anthropogenic matrix.  相似文献   

12.
The relationships between the shell height of the predatory gastropod Cryptonatica janthostoma and the shell length of its typical prey, the bivalve Ruditapes philippinarum, and the diameter of the borehole on the prey shell resulting from a successful attack of the predator were experimentally found and assessed statistically. The shell height of C. janthostoma calculated retrospectively from the borehole diameter using the obtained relationships was 17–52 mm. The prey of C. janthostoma are burrowing bivalves, whose populations are affected by the predator to a varying degree. In populations of medium-sized mollusks (R. philippinarum, Protothaca euglypta, P. jedoensis, and others), C. janthostoma feeds on mollusks larger than 7–10 mm; in species with a shell length greater than 100 mm (Callista brevisiphonata, Saxidomus purpuratus), it eats specimens of 10–58 mm. C. janthostoma apparently has no effect on populations of small-sized mollusks (Anisocorbula venusta) and mollusks with an active avoidance response (Clinocardium californiense).  相似文献   

13.
The soybean pod gall midge, Asphondylia yushimai, is known to utilize Laurocerasus zippeliana (Rosaceae) and Osmanthus heterophyllus (Oleaceae) as autumn–spring hosts. In addition, ivy, Hedera rhombea (Araliaceae), was thought to be a candidate for an additional autumn–spring host. However, our genetic analysis indicated that no haplotypes of the ivy fruit gall midge, Asphondylia sp., were identical to any of the haplotypes of A. yushimai. Furthermore, the life-history traits of the ivy fruit gall midge, such as voltinism, host-plant range, lower development threshold temperature (LDT), and developmental speed, were clearly different from those of A. yushimai. Thus, the results from genetic analysis and life-history traits revealed that the ivy fruit gall midge was not identical to A. yushimai and that H. rhombea is not an additional autumn–spring host plant for A. yushimai. We also discovered through morphological observation and genetic analysis that A. yushimai is distributed in Hokkaido and South Korea, and that the ivy fruit gall midge exhibits host plant alternation, utilizing both the fruit of Phytolacca americana (Phytolaccaceae) and the flower buds of Paederia foetida (Rubiaceae) as spring–autumn hosts.  相似文献   

14.
Two new species of the feather mite genus Proctophyllodes Robin, 1868 (Analgoidea: Proctophyllodidae) are described from two passerine birds (Passeriformes) in Europe: Proctophyllodes markovetsi n. sp. from the tawny pipit Anthus campestris (L.) (Motacillidae) and P. loxiae n. sp. from the red crossbill Loxia curvirostra (L.) (Fringillidae). Males of P. markovetsi are most clearly distinguished from the closely related P. tchagrae Atyeo & Braasch, 1966 by having greater terminal lamellae (30–40 × 20–25 µm), the tips of genital arch curved medially, and the corolla of the anal sucker with 14–15 denticles; females of this species are characterised by the terminal appendages distinctly longer than the lobar region width. Males of P. loxiae differ from the closest species, P. fuchsi Mironov, 1997, by having smaller terminal lamellae (45–50 × 22–28 μm), the genital organ extending beyond the posterior margin of lamellae by half their length; females can be distinguished by having the terminal cleft noticeably wider than long (28–30 × 35–40 μm).  相似文献   

15.
The fate of hybrids and the temporal and spatial dynamics of hybrid zones depend on hybrid fitness in comparison to non-hybrids. We studied cross-pollination among Hancornia speciosa varieties and compared progeny fitness in a nursery to address whether hybrid fitness differed from non-hybrids and whether maternal and paternal taxa contribute differentially to offspring fitness. This species has edible fruit pulp that is used as a raw material for candies, ice cream, and juice by small- and medium-sized enterprises in Central-West and Northeast Brazil. We genotyped 258 adults from a germplasm collection and 320 seeds using seven microsatellite loci to estimate genetic parameters and determine pollen donors. Fitness components, days to shoot, growth rate (mm/day), leaf width (mm), leaf length (mm), stem diameter (mm), and plant height (cm) were analyzed in 200 individuals. Genetic diversity and polymorphism did not differ neither between adults and progeny arrays nor among the four varieties. Genetic differentiation among varieties (F CT?=?0.019, p?<?0.001) and among populations within varieties (F SC?=?0.053, p?<?0.001) was significant but low. We detected mating among the four varieties, and no self-pollination was observed in parentage analysis, confirming that H. speciosa is self-incompatible with a high outcrossing rate (t m?=?0.990, SE?=?0.007). No significant effect of heterosis or exogamic depression was detected for any fitness component, but maternal contribution significantly affected plant height.  相似文献   

16.
Two new species of Gentianella (Gentianaceae, Gentianeae, Swertiinae), G. grantii and G. wayqecha, are described from Departamento Cusco, Peru. These two species differ from other Peruvian species of Gentianella in a combination of stems 10–100 cm long; no rosette of basal leaves; cauline leaves 10–75 mm long; flowers in thyrses; and corollas 14–26 mm long, campanulate, and adaxially glabrous. The leaves of G. grantii consist of an appressed pseudopetiole and a spreading, narrowly elliptic-oblong to linear blade; the corollas are lavender; and the corolla lobes are 0.6–0.7× as long as the tube. Gentianella grantii is similar to G. lythroides, of Bolivia, but differs in having more closely spaced leaves and less deeply lobed corollas. The leaves of G. wayqecha are sessile, lanceolate to ovate; the corollas are rose-violet; and the corolla lobes are 0.75–1.35× as long as the tube. Gentianella wayqecha is similar to G. rapunculoides, of Colombia and Ecuador, and G. ruizii, of Peru, but differs from both in its adaxially glabrous corollas and from G. rapunculoides in its less deeply lobed corollas. Both G. grantii and G. wayqecha grow in moist habitats near tree line, and are known only from a area northeast of the city of Cusco.  相似文献   

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18.
To test the effects of invasion by strawberry guava trees (Psidium cattleianum) on the forest soil ecosystem, we compared soil properties between pairs of adjacent native and P. cattleianum stands. We set up six study sites that had developed under different mean annual precipitation levels in the Ko'olau Mountains on the island of O'ahu, Hawai'i. Accumulated litter mass and soil pH decreased with precipitation in the native stands. Invasion by P. cattleianum increased the amount of litter and reduced the differences in soil water content and pH among the sites. We compared the decomposition process using the Tea Bag Index, which is determined by the difference in dry mass of commercially available green and rooibos teas in nylon mesh bags before and after 90 days of burial. Psidium cattleianum increased the initial litter decomposition rate irrespective of precipitation and other soil properties. On the other hand, P. cattleianum increased the long-term litter stabilization factor of the Tea Bag Index in wetter sites. The accumulation of litter was likely caused by indirect effects of P. cattleianum through the alteration of soil moisture properties. In summary, this study shows that invasion by P. cattleianum could alter the soil properties in both wet and mesic sites, suggesting the possibility of change in composition and/or function of decomposers.  相似文献   

19.
Two new species of the genera Uroleucon Mordvilko, 1914 and Pleotrichophorus Börner, 1930 are described from Kazakhstan. Uroleucon dzhungaricum sp. n. feeding on Senecio nemorensis L. (Asteraceae) in the Dzhungar Ala Tau is closely related to U. minor (Börner, 1940). Both these species differ from the closely related U. solidaginis (Fabricius, 1794) in a smaller length ratio between the processus terminalis and the 3rd antennal segment (0.8–1.0 versus 1.0–1.5). The new species differs from U. minor (Born.) in a greater number of the secondary rhinaria on the 3rd antennal segment of the apterous viviparous females (21–37 versus 15–21), in a fewer number of hairs on the cauda (10–16 and 15–23), and in the host plant. Pleotrichophorus ugamicus Kadyrbekov, sp. n. feeding on Artemisia santolinifolia Turcz. is described from the Sairam-Ugam Natural Park (Southern Kazakhstan). The new species is similar to P. glandulosus (Kaltenbach, 1846) and P. achilleae Holman, 1965. Pleotrichophorus ugamicus sp. n. differs from these species in the length ratio of the processus terminalis to the base of the 6th antennal segment (4.1–5.0 versus 5.0–9.0 and 5.1–6.2), in that of the ultimate rostral segment to the 2nd segment of the hind tarsus (0.68–0.76 versus 0.80–0.97 and 0.80–0.90), and in the host plant. This species differs from P. glandulosus in the ratio of the length of dorsal hairs on tergites I–V to the basal diameter of the 3rd antennal segment (1.0–1.2 and 1.4–1.7). In addition, the new species differs from P. achilleae in the length ratio of the 3rd antennal segment to the 6th segment (0.56–0.66 versus 0.70–0.87) and to the processus terminalis (0.67-0.82 versus 1.39–1.80), as well as in the shape of the dorsal hairs. A key to the Palaearctic species of the genus Pleotrichophorus is presented.  相似文献   

20.
A new species of labrid fish Oxycheilinus samurai sp. nov. is described on the basis of five specimens from the Ryukyu Islands, Japan, and Panay Island, the Philippines. The new species is most similar to the Indo-West Pacific species Oxycheilinus orientalis in having a slender compressed body, 12 pectoral-fin rays, a blackish blotch around the anterior portion of the lateral-line anterior series, and a dark blotch basally on the membrane between the first and second dorsal-fin spines. However, O. samurai can be distinguished from O. orientalis by the following combination of characters: gill rakers 4 + 7–8; snout rounded with maximum circumference 49.8–63.5 % of standard length (SL); interorbital width 7.7–9.2 % of SL; caudal-peduncle depth 13.8–15.3 % of SL; posterior margin of caudal fin white; black or dark red area just before white posterior margin of caudal fin; poorly defined blackish blotches on inner surface of opercle in preserved specimens.  相似文献   

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