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1.
A new species Dolichopteryx minuscula is described on the basis of three specimens [49.4–59.6 mm in standard length (SL)] collected from the Indo-West Pacific. The new species is characterized by pouchlike eyes with a small lens (lens diameter 2.2% SL), an adipose fin, the anal fin base originating posterior to the dorsal fin base, and 16–17 (= 5–6 + 1 + 10–11) gill rakers. Total fecundity was relatively low, only 658 ova being obtained from one specimen, despite the ovary being mature. Ovarian eggs were clearly subdivided into “undeveloped” (0.1–0.7 mm diameter classes, n = 561) and “developed” (1.0–1.3 mm classes, n = 97) groups, based on their frequency distribution. Such relatively low fecundity and frequency distributions of ovarian eggs suggest that Dolichopteryx species spawn iteratively during spawning season.  相似文献   

2.
Agave rzedowskiana is described and illustrated from the states of Sinaloa and Jalisco, Mexico. This species is a member of subgenusLittaea (Tagliabue) Baker “groupStriatae” of Baker. It is compared withA. petrophila García-Mend. & E. Martínez andA. dasylirioides Jacobi & Bouché.
Resumen  Se describe e ilustraAgave rzedowskiana de los estados de Sinaloa y Jalisco, México. La especie pertenece al subgéneroLittaea (Tagliabue) Baker “Grupo Striatae” de Baker. Se le compara conA. petrophila García-Mend. & E. Martínez yA. dasylirioides Jacobi & Bouché.
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3.
Traditional Knowledge and Management of Feijoa (Acca sellowiana) in Southern Brazil. This paper investigates traditional knowledge of the use and management of Acca sellowiana in southern Brazil. Fifty-six informants from three rural communities were assigned to one of four subgroups (“maintainers,” “managers,” “cultivators,” or “users”) based on their responses regarding management and use of A. sellowiana. Traditional knowledge related to use of this species is widespread among rural residents, but traditional knowledge related to management is fragmented depending on whether one uses, manages, or cultivates the species. Knowledge held in rural communities suggests that A. sellowiana could play an expanded role in local economies as well as biodiversity conservation. We suggest that participatory research could stimulate greater local use as well as on-farm conservation of A. sellowiana.  相似文献   

4.
5.
A new species, Dolichopteryx rostrata, is described on the basis of a single specimen (66.2 mm in standard length) collected west of the Hebrides Islands, eastern North Atlantic Ocean. The new species is characterized by an elongate snout and head, small pouchlike eyes, an adipose fin, short dorsal fin base, anal fin base originating under dorsal fin base, a clear longitudinal suborbital brownish band extending forward from behind posterior margin of orbit to snout tip, and 41 (=26 + 15) vertebrae. Total fecundity is low; the ovarian eggs number only 473, despite the ovary having developed ova. Ovarian eggs could be clearly subdivided into an “undeveloped group” (0.1–0.7 mm diameter classes, n = 405) and a “developed group” (0.9–1.3 mm classes, n = 68), based on their frequency distribution. Supplementary material to this paper is available in electronic format at http://dx.doi.org/10.1007/s10228-005-0306-2  相似文献   

6.
One new species and one new variety ofBauhinia subg.Phanera sect.Caulotretus are described. Both taxa are tendrilled lianas with woody fruit and both are apparently endemic to Southern Bahian moist forest.Bauhinia carvalhoi has the smallest entire leaves known in the section.Bauhinia angulosa var.bahiana apparently replaces, in “Mata higrófila sul Bahiana”, the typical variety from southeastern Brazil. A key to the three taxa of this section known from Bahia is provided.  相似文献   

7.
A new species of notothenioid fish, Pogonophryne bellingshausenensis n. sp., is described from the Bellingshausen Sea, Antarctica. The new species belongs to the dorsally-spotted “mentella” group of the genus and is characterized by having a short (about 13% SL) mental barbel with a short (about 16% of barbel length), narrow (barely wider than the stalk), and relatively inconspicuous terminal expansion composed of short, irregular, fingerlike processes. Compared to most other dorsally-spotted species of Pogonophryne (“barsukovi”, “marmorata”, and “mentella” groups), P. bellingshausenensis has a relatively wide (about 7% SL) interorbital region. An unspotted patch on the median dorsal surface of the head, posterior to the posttemporal ridges and anterior to the first dorsal fin, has not been observed previously in any dorsally-spotted species. The holotype was collected at 1,947 m, one of the deepest records for any species of Pogonophryne. A revised key to the ten species of the “mentella” group of Pogonophryne is also provided.  相似文献   

8.
Chirita luochengensis, a new species of Gesneriaceae from Guangxi, China, is described and illustrated. The new species is similar to C. linearifolia in leaf shape, but can be distinguished by the apex of leaf blade obtuse to round, corolla purplish, 3–4.2 cm long, corolla tube 2–2.5 cm long, 10–15 mm diameter at the mouth, staminodes 3, disc ca. 2.5 mm in height, pistil 2.5–3 cm long, stigma obtrapeziform, 4 mm long, and apex shallowly 2-lobed.  相似文献   

9.
A morphological analysis ofPhysalis and several closely related genera, with emphasis on a group of species known as “atypicalPhysalis,” showed that two of the atypical species are better treated as a distinct genus.Tzeltalia is described and two new combinations are made:T. amphitricha andT. calidaria. Restricted to the highlands of Chiapas, Mexico, and adjacent Guatemala,Tzeltalia is distinguished fromPhysalis by a combination of characters including shrubby habit; fasciculate flowers; lobed corolla; scabrate pollen; and non-invaginated, partially open, coriaceous, and reticulate-veined fruiting calyx.
Resumen  El análisis de un grupo de especies atípicas dePhysalis y otros géneros relacionados demostró que dos especies deben considerarse como otro género. Se describeTzeltalia, un género restringido a los altos de Chiapas, México, y Guatemala y se hacen dos nuevas combinaciones,T. amphitricha yT. calidaria.Tzeltalia se distingue dePhysalis por una combinación de caracteres que incluyen un habito arbustivo, flores fasciculadas, corola lobulada, polen escabroso, cáliz del fruto no invaginado, parcialmente abierto, coriáceo y con venación reticulada.
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10.
Remarkable ophidiid larva (Neobythitinae) from New Guinean waters   总被引:1,自引:1,他引:0  
A new type of ophidiid larva referred to the Neobythitinae is described on the basis of one specimen (22.5 mm in standard length: SL) found in the “Dana” flatfish larval collection from New Guinean waters. It is characterized by a very high body (ca. 48% SL), with a single elongate first dorsal-fin ray and protruding abdominal cavity with a long fleshy appendage at its posteroventral end. Generic and specific affinities of the larva are discussed. It is supposed that the larva belongs to one of the Pycnocraspedum species, probably to P. squamipinne.  相似文献   

11.
Sicyos lirae is described as a new species from Chiapas, Mexico, and Guatemala. It grows in zones with primary or secondary montane rain forest at elevations between 1400 and 3800 meters. In Guatemala the species is commonly called “güisquil de ratón.” It is similar toSicyos galeottii Cogn., from which it differs in blade consistency, shape of the stigma lobes, and several important ovary and fruit characters.  相似文献   

12.
Three genera of lagomorphs, Prolagus, Lagopsis, and “Amphilagus,” were identified during a revision of the lagomorph material from Sandelzhausen (MN5, Early/Middle Miocene boundary, southern Germany). Evidence of two morphological and dimensional classes were observed at some tooth positions in Prolagus (some p3 show an unmistakable P. oeningensis morphology, others closely resemble P. crusafonti), but not at other tooth positions (e.g., M1–2). Insufficient data from Sandelzhausen precludes identification of two different species of Prolagus from this locality, and to define the characteristics of the possible P. crusafonti-like species. Thus, all Prolagus specimens have been classified as P. aff. oeningensis. The genus Lagopsis is represented by L. cf. penai, whose presence is compatible with a MN5 age. The relative abundance of Lagopsis to Prolagus may indicate relatively cool and wet palaeoclimatic conditions. The largest primitive lagomorph species from continental Europe is present at Sandelzhausen. Morphological and dimensional comparisons with other European primitive lagomorphs exclude any affinity with the genera Eurolagus and Titanomys and with the species included in “Amphilagus ulmensis”. Some common features with “Amphilagus antiquus” were observed, although they are not sufficient for the attribution to this taxon. Until there is a general revision of European primitive lagomorphs, the Sandelzhausen giant lagomorph is classified as “Amphilagus” sp. Its origins, whether from evolution within Europe or migration from Asia, remain unknown.   相似文献   

13.
14.
Four flattened Gracilaria species have been reported from Taiwan: G. spinulosa, G. vieillardii, G. textorii and G. punctata, identified based on branching pattern, the presence or absence of spines, and characters that often vary seasonally. Gracilaria spinulosa was originally described from the type locality, Tainan. Species with toothed margins are usually referred to G. “vieillardii”; those with smooth margins to G. “textorii”, and those with smooth margins and dark spots scattered over the blade to G. “punctata”. Molecular analyses show that specimens with marginal teeth cluster in three different groups: a G. “vieillardii” clade, a G. spinulosa clade, and a clade sister to G. spinulosa. An undescribed species comprises the third clade, which is distinguished by its relatively large gonimoblast cells and weakly developed tubular nutritive cells. The three clades can be separated by the character of the tubular nutritive cells, the size of gonimoblast cells and certain vegetative features. Plants with entire margins form a single clade characterized by cystocarps with basal tubular nutritive cells and their absence in the cystocarp cavity. They are nested in the Hydropuntia complex and are referred to as Gracilaria “punctata” here. The records of G. textorii and G. punctata from Taiwan require reinvestigation in comparison with the Japanese species.  相似文献   

15.
The species ofChamaesyce classified by Boissier as the “Pleiadeniae” are revised in light of presently available collections. Six species are accepted and new combinations are proposed forC. nana, C. setosa, C. tamanduana, andC. viscoides. Although these herbaceous perennials of cerrado vegetation of Brazil, northern Argentina, and adjacent countries are distinctive ecologically and geographically, cladistic analysis does not support their recognition as a monophyletic group.  相似文献   

16.
A seaweed with the local name “endong” is a rare eucheumoid variety that has recently been farmed in Tawi-Tawi, southern Philippines. Local farmers describe it as “eel-like” because of its long, slender and smooth thalli. Being somewhat similar in appearance to the dominantly farmed seaweed “tambalang” (Kappaphycus alvarezii var. tambalangii), farmers mix their harvests of “endong” with those of “tambalang”. We analyzed the hydrocolloid extract from “endong” using spectroscopic and chemical techniques. The extract’s infrared and nuclear magnetic resonance (1H and 13C) spectra, and sulfate and 3,6-anhydrogalactose contents revealed carrageenan of the iota-type, similar to extracts from another farmed species, Eucheuma denticulatum. This result implies that “endong” carrageenan exhibits physico-chemical properties different from those of kappa-carrageenan of “tambalang”. The findings of this study are of significance to the seaweed industry, as carrageenan quality problems could potentially arise from a mixed harvest. Seaweed farmers are advised to separate their harvests of “endong” and “tambalang”. Presented at the 19th International Seaweed Symposium, Kobe, Japan  相似文献   

17.
Den sharing by conspecific spiny lobsters (aggregation) is modulated by chemical attraction but may confer several, not necessarily mutually exclusive, antipredator byproduct benefits: a “guide effect”, which only benefits the individual attracted to a sheltered conspecific; a “dilution effect”, which reduces per-capita risk of predation simply through aggregation; or active “group defense”. Each potential benefit has a different set of predictors (relationships between aggregation and conspecific or predator densities), but conflicting results could suggest the simultaneous operation of more than one benefit. These predictions were tested for coexisting Panulirus guttatus (a reef-obligate) and Panulirus argus (a temporary reef-dweller) using data collected during 11 surveys on fixed sites over a coral reef in Mexico. P. guttatus greatly outnumbered P. argus, but P. argus showed a greater tendency to aggregate. All three benefits of den sharing operated for the more social P. argus, with “group defense” being of the most benefit for larger individuals, and the “guide” and “dilution” effects for smaller individuals recently immigrating into the reef habitat and sharing dens with larger conspecifics. P. guttatus did not display “group defense” and its aggregations appeared to be modulated by the interplay between attraction and aggressive behaviors. This species relied more on solitary crypticity, especially at larger sizes, but appeared to benefit from a “guide effect” at high conspecific densities. In experimental tanks, each species tended to aggregate when tested separately, but when tested jointly, aggregation among P. guttatus was significantly reduced. The experimental results reflect the differential patterns of aggregation between the fore-reef, where P. guttatus dominated, and the back-reef, where coexistence of both species was greater.  相似文献   

18.
R. M. Beach  J. W. Todd 《BioControl》1986,31(3):237-242
Field grown foliage from the resistant soybean [Glycine max (L.) Merrill] breeding line GAT “81–327” and the susceptible cultivar “Ransom” was used to rear unparasitized larvae of the soybean looper (SBL),Pseudoplusia includens (Walker), and larvae parasitized byCopidosoma truncatellum (Dalman). SBL larvae, whether parasitized or not, consumed more foliage when fed “Ransom”. Unparasitized larvae reared on “81–327” had longer developmental times and suffered greater mortality than unparasitized larvae reared on “Ransom”. Parasitization of SBL larvae byC. truncatellum increased total foliage consumption of both soybean lines. Parasitized larvae reared on the resistant “81–327” weighed less and yielded fewer parasitoid adults.
Résumé Des larves dePseudoplusia includens (Walker) parasitées ou non parCopidosoma truncatellum (Dalman) ont été nourries des feuilles de deux lignées de soja [Glycine max (L.) Merrill] l'une, GAT “81–327” résistante et l'autre, “Ransom” sensible. Les larves deP. includens qu'elles soient parasitées ou non consommaient plus de feuillage lorsqu'elles étaient nourries de la lignée “Ransom”. Les larves non parasitées élevées sur “81–327” avaient un cycle de développement beaucoup plus long et un taux de mortalité beaucoup plus élevé que les larves non parasitées élevées comparativement sur feuilles de “Ransom”. Par contre, les larves parasitées manifestaient une consommation accrue du feuillage des deux lignées de soja. Les larves parasitées élevées sur les feuilles de la variété résistante GAT “81–327” pesaient moins et produisaient moins également de parasites adultes.
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19.
Dentalium antiquum is one of two moderately well-known Devonian “scaphopods” in the German literature. Examination of the type material and a few specimens in other institutions indicates more individual variability than is to be expected in species of the molluscan class Scaphopoda. The species is transferred with question toColeolus Hall, a fossil presumed to be a calcareous “worm” tube.   相似文献   

20.
The brook silverside, Labidesthes sicculus (Cope), is unique in Canadian waters, as it completes its life cycle in 1 year. Previous studies based on scale ageing had suggested the species was an “annual,” but we confirmed this for the first time by otolith analysis. Growth rates from both back-calculation, and the Gompertz model, indicated an asymptote near the end of the summer, and average summer growth rates of 0.77 and 0.70 mm/day, respectively. The Gompertz model gave the best fit (n = 201, r = 0.744) with an L∞ of 85.4 mm TL, and instantaneous growth rate, g, of 0.0264. Back-counting daily growth increments allowed us to show that broods of young fish were produced throughout the summer, from late May to mid August, with maximum hatch taking place in mid-July. The species is a “batch” (serial) spawner, with only a fraction of the eggs ripening in the ovary and being released at as yet undetermined intervals. Eggs of the larger immature fish in the first summer developed from 0.05 to 0.21 mm in diameter (preserved) by fall, and in mature fish of the following spring and summer, developed to 1.2 mm in diameter (preserved), 1.4 mm fresh, at spawning. Attached to each egg was a filament averaging 2.0 cm in length, adhesive in nature, and presumably for attachment to vegetation. The egg also had microscopic hairs on its surface. No evidence was found to support temperature-dependant sex determination, nor were embryos or sperm found in the ovaries of spawning females, unlike Labidesthes sicculus vanhyningi, (the southern subspecies) which has internal fertilization. The Canadian species possesses a genital papilla through which the eggs were released, and an apparently much smaller male genital papilla than the southern subspecies.  相似文献   

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