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211.
Lavatera assurgentiflora (Malvaceae) is one of four species of the genus Lavatera native to California and Baja California. Two geographically defined subspecies are recognized: L. a. assurgentiflora on the northern islands and L. a. glabra on the southern islands. We isolated nine polymorphic microsatellite loci that amplify in both subspecies of L. assurgentiflora. Substantial levels of polymorphism were observed at many of the loci. Four loci exhibited more than 10 alleles, polymorphism information content ranged from 0.4 to 0.8, and up to six alleles were found in some individuals, supporting reports that these taxa are hexaploid. All loci also amplified in Lavatera lindsayi from Guadalupe Island, and we anticipate that they will cross‐amplify in other California Lavatera species as well.  相似文献   
212.
Mariana Swiftlets (Aerodramus bartschi) are federally listed as endangered, with populations currently limited to just three islands in the Mariana Islands plus an introduced population on the Hawaiian island of O'ahu. Before efforts are made to reintroduce Mariana Swiftlets to other islands in the Mariana archipelago, additional information is needed concerning their breeding biology. Therefore, our objective was to examine the reproductive biology of Mariana Swiftlets over five annual cycles on the Hawaiian island of O'ahu. This introduced population used a human‐made tunnel for roosting and nesting, and was studied as a surrogate to negate interference with endangered populations in the Mariana Islands. Active nests (= 478) were observed in every month of the year, with peak nesting activity between May and September. All clutches consisted of one egg. Mean duration of incubation and nestling periods were 23.9 d (range = 18–30 d, = 233) and 55.0 d (range = 41–84 d, = 228), respectively. Estimated nest success was 63%. Over half (52%) of nest failures were attributed to eggs found on the tunnel floor. Predation by rats (Rattus spp.) was also an important cause of nest failure and often resulted in the loss of most active nests. However, Mariana Swiftlets did re‐nest after these predation events. Our results suggest that rat predation of both nests and adults may limit growth of the Mariana Swiftlet population on O'ahu, and could also affect the chances for successful establishment of relocated populations in the Mariana Islands. Another limiting factor on O'ahu is that only one nesting site is apparently available on the island. Current goals for downlisting Mariana Swiftlets from endangered to threatened include establishing populations on Guam, Rota, Aguiguan, and Saipan. To meet these goals, the population of Mariana Swiftlets on O'ahu can be important for testing reintroduction techniques, learning more about the natural history of these swiftlets, and providing individuals for reintroduction efforts in the Mariana Islands.  相似文献   
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214.
The genusScrophularia in the Iberian Peninsula and Balearic Islands comprises two sections,Scrophularia andCanina G. Don. Analyses were carried out on flower production, flower duration and their sexual phases, pollen and nectar production together with observations on their pollinators. Nectar production is correlated with corolla size and pollen production with anther size. The taxa of sect.Scrophularia show greater nectar and pollen production than those of sect.Canina. Also, those of the first section produce more ovules per ovary than those of the second group, production being correlated with the ovary size.Some observations on floral and reproductive biology in some species ofScrophularia from the Iberian Peninsula and the Balearic Islands. I.  相似文献   
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216.
A detailed uni‐ and multivariate analysis of within‐island geographical variation in scalation and body dimensions of the lacertid lizard, Gallotia atlantica, from Lanzarote (and two neighbouring offshore islets) was carried out. Two main morphological groupings were detected: four populations clustered within a putative malpaís group, i.e. from relatively recent volcanic lava fields (seven populations were sampled from these areas), while the other 19 populations (including the three remaining malpaís populations, and those from the offshore islets of Montaña Clara and Alegranza) also clustered together. Thus, while there is a tendency for occupation of malpaís areas to be related to morphological variation, this model does have some inconsistencies. The differentiated malpaís group comprises populations from two geographically isolated areas, one from the central‐western part of the island (Timanfaya) and the other from the north (Malpaís de la Corona). The divergence of these populations is considered to have arisen recently, rather than their being relicts of an ancient, formerly widespread, lineage. The morphological variation partially supports the previous use of two different subspecies to describe the within‐island variation. However, if such a scheme were applied then one of the subspecies would need to encompass populations from the geographically separated southern Timanfaya and Malpaís de la Corona areas, as opposed to just the latter. We reject previous observations that either malpaís individuals in general, or those corresponding to the north‐eastern subspecies, are larger than individuals from other areas. The pattern of morphological variation of G. atlantica within Lanzarote is less pronounced but shows some similarities with patterns of morphological variation in lizards from neighbouring islands. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society, 2005, 85 , 395–406.  相似文献   
217.
Six specimens of Dormitator latifrons caught in Laguna del Cementerio, Isabela Island, represent the first record of this species in the Galapagos Islands.  相似文献   
218.
Pseudoniphargus candelariae n. sp. is described from a ground-water-fed well in Tenerife (Canary Islands) and is compared with all species known from Macaronesia. The new species has one unique character (spination of palmar angle of gnathopod 1 sexually dimorphic) and presents furthermore a new combination of morphological features not found in other species of the genus in the area studied.  相似文献   
219.
Samples of the meadow brown butterfly, Maniola jurtina , were collected from all five of the Canary Islands where it occurs. The butterflies were scored for several spotting characters on both fore- and hindwings and assessed for damage from predators.
The analysis reveals considerable interisland heterogeneity for spotting characters and suggests that the populations fall into two relatively distinct, homogeneous groups, which inhabit the islands of Gran Canaria and La Gomera, on the one hand, and Tenerife, El Hierro and La Palma, on the other.
The main predators are lizards and insectivorous birds. Predator damage is non-random in the following respects: males are more damaged than females; high spot male phenotypes are more damaged than low ones early in the flight period (April-May); symmetrical damage, probably acquired while resting, is commoner in females, while asymmetrical damage is more characteristic of males. Damage generally increases in both sexes through the flight period.
Comparison of the bulked Canary Island samples with museum material from North Africa and Iberia suggests that the former area is the more likely source of the island populations. However, samples from two islands more resemble Iberian stock and it is suggested that the butterfly may have colonized the islands, either by introduction or immigration, on two occasions.  相似文献   
220.
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