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Questions: Both species turnover and intraspecific trait variation can affect plant assemblage dynamics along environmental gradients. Here, we asked how community assemblage patterns in relation to species turnover and intraspecific variation differ between endemic and non-endemic species. We hypothesized that endemic species show lower intraspecific variation than non-endemic species because they tend to have high rates of in situ speciation, whereas non-endemic species are expected to have a larger gene pool and higher phenotypic plasticity.
Location: La Palma, Canary Islands.
Methods: We established 44 sampling sites along a directional gradient of precipitation, heat load, soil nitrogen, phosphorus and pH. Along this gradient, we estimated species abundances and measured three traits (plant height, leaf area and leaf thickness) on perennial endemic and non-endemic plant species. In total, we recorded traits for 1,223 plant individuals of 43 species. Subsequently, we calculated community-weighted mean traits to measure the relative contribution of species turnover, intraspecific variation and their covariation along the analysed gradient.
Results: The contribution of intraspecific variation to total variation was similar in endemic and non-endemic assemblages. For plant height, intraspecific variation explained roughly as much variation as species turnover. For leaf area and leaf thickness, intraspecific variation explained almost no variation. Species turnover effects mainly drove trait responses along the environmental gradient, but intraspecific variation was important for responses in leaf area to precipitation.
Conclusions: Despite their distinct evolutionary history, endemic and non-endemic plant assemblages show similar patterns in species turnover and intraspecific variation. Our results indicate that species turnover is the main component of trait variation in the underlying study system. However, intraspecific variation can increase individual species’ fitness in response to precipitation. Overall, our study challenges the theory that intraspecific trait variation is more important for the establishment of non-endemic species compared with endemic species.
Recently, it has been hypothesized that the wide distribution of A. fiuzai Salles & Lugo-Ortiz is due to a wide diagnosis and conflicting keys. The same arguments can be applied to A. kallawaya Nieto. In order to test this hypothesis, we revised the type material of A. fiuzai, literature of A. kallawaya, and part of the recorded specimens in Brazil. As a result, three new species from previous records are recognized: Apobaetis pasternakae sp. nov., former A. fiuzai in Amazonas, Roraima and Maranhão states; Apobaetis jaquelinae sp. nov., former A. fiuzai in Rondônia State; Apobaetis luanae sp. nov., former A. kallawaya in Rondônia State. The new data showed that A. fiuzai does not occur in the Amazon Biome and A. kallawaya does not occur in Brazil. Records of A. fiuzai that could not be reviewed in this study are treated as putative and should be evaluated in the light of the new evidence. We also studied the intraspecific variation in A. fiuzai and A. pasternakae sp. nov. The pigment pattern of the nymphs was not considered a robust characteristic for the species differentiation due to the wide variation in and between populations, and interspecific similarity of many features. On the other hand, classical morphological characters such as mouthparts, legs, spines of terga, paraproct and caudal filaments have minimal variation, stable and reliable for specific identification.
Three new species of the family Pyrgodesmidae Silvestri, 1896 from the Udzungwa Mountains are described: Cryptocorypha geminiramus sp. nov., Cryptocorypha cactifer sp. nov., and Cryptocorypha exovo sp. nov. Several additional, unidentifiable pyrgodesmids from the Udzungwa Mountains are recorded. Elythesmus enghoffi Hoffman, 1978 (Cryptodesmidae Karsch, 1880), is recorded from the East Usambara (type locality), West Usambara, Uluguru, Nguru (Kanga) and Udzungwa Mountains, and its variation in size and body ring numbers is analyzed. The surface sculpture of pro- and metazonites is discussed.
Ordovician ectocochleate cephalopods of the order Lituitida Starobogatov, 1983, mainly from erratics of the Orthoceratite Limestone embedded in Pleistocene glacio-fluvial sediments in Germany, Poland and the Kaliningrad Region of Russia are revised. In total, seven genera (Rhynchorthoceras, Ancistroceras, Angelinoceras, Holmiceras, Lituites, Trilacinoceras, Cyclolituites) and 28 species are identified. Eleven species are newly described: Rhynchorthoceras kranepuhlense sp. nov., R. rugium sp. nov., Holmiceras havelense sp. nov., Lituites baculus sp. nov., L. bottkei sp. nov., L. clavis sp. nov., L. dewitzi sp. nov., L. kruegeri sp. nov., L. nebeni sp. nov., Trilacinoceras filix sp. nov. and T. knoefleri sp. nov. The concept of several taxa described in the 19th century, including the ambiguous species L. lituus de Montfort, 1808 and L. perfectus Wahlenberg, 1818, is refined. Neotypes are proposed for the latter two species.
Macrophotographs in series taken by Alice Abela on sandy coastal dunes in Santa Barbara and San Luis Obispo Counties, CA in 2010–2021 supplement and enhance F. X. Williams (1928) study of the ecology and nesting behavior of the trapdoor spider-hunting spider wasp Aporus (Plectraporus) hirsutus (Banks) (Hymenoptera: Pompilidae: Aporini). Abela’s macrophotographs and observations provide new details of adult wasp feeding, functional morphology, hunting, digging and prey transport, and host spider trapdoor, entrance, burrow structure, host capture and escape activity. Newly reported host records from this study and online photographs expand A. hirsutus host selection in the large wafer-lid trapdoor spider genus Aptostichus Simon (Araneae: Mygalomorphae: Euctenizidae). The A. hirsutus California geographic distribution map by Wasbauer and Kimsey (1985) is updated, thereby providing a broader definition of intraspecific variation in this species.
Various mechanisms can facilitate the success of plant invasions simultaneously, but may be difficult to disentangle. In the present study, plants of the range-expanding species Bunias orientalis from native, invasive and naturalised, not yet invasive populations were compared in a field common garden over two years. Plants were grown under two nitrate-regimes and multiple traits regarding growth, defence, antagonist loads and reproduction were measured. A rank-based clustering approach was used to assign correlated traits to distinct suites. These suites were analysed for "syndromes" that are expressed as a function of population origin and/or fertilisation treatment and might represent different invasion mechanisms. Indeed, distinct suites of traits were differentially affected by these factors. The results suggest that several preadaptation properties, such as certain growth characteristics and intraspecific chemical variation, as well as post-introduction adaptations to antagonists and resource availability in novel habitats, are candidate mechanisms that facilitate the success of invasive B. orientalis in parallel. It was concluded that rank-based clustering is a robust and expedient approach to integrate multiple traits for elucidating invasion syndromes within individual species. Studying a multitude of traits at different life-history and establishment stages of plants grown under distinct resource treatments reveals species-specific trade-offs and resource sinks and simplifies the interpretation of trait functions for the potential invasive success of plants.
Recent collections of pseudoscorpions resulted in a first record and a new species from Iran. Olpium omanense Mahnert, 1991 originally described from Oman is recorded for the first time from Iran. Three congeneric species with similar morphometric characters and trichobothrial patterns, Olpium intermedium Beier, 1959, O. lindbergi, Beier, 1959 and O. omanense can be separated by the setal numbers on the posterior margin of the carapace and tergite I. Also, specimens reported as Olpium lindbergi Beier, 1951 from Pakistan were probably misidentified and belong to O. omanense. The new species Cardiolpium bisetosum sp. nov. is described based on males from Markazi province, western Iran. Morphometric data are given in comparison to related species.
The African species Cheiracanthium furculatum Karsch, 1879 was recognised as being introduced to Germany and is re-described and illustrated in the present study. C. tenuipes Roewer, 1961 is recognised as a junior synonym of C. africanum Lessert, 1921 (new synonymy); both subspecies of C. strasseni Strand, 1915, namely C. strasseni strasseni Strand, 1915 and C. strasseni aharonii Strand, 1915, are recognised as junior synonyms of C. mildei L. Koch, 1864 (new synonymies). Photographic images of the copulatory organs of the types of C. cretense Roewer, 1928, recently synonymised with C. mildei, are provided and discussed in the course of intraspecific variation in C. mildei. The female holotype of C. rehobothense Strand, 1915 is re-described and illustrated. Relations of C. rehobothense to other Cheiracanthium species are discussed.