Background Although Trapa is a well-defined genus of distinctive freshwater plants with accumulations of extensive morphological and embryological autapomorphies, its phylogenetic relationships have long been unclear. Formerly placed in the monotypic family Trapaceae, Trapa is now recognized as sister to Sonneratia within Lythraceae s.l., although both genera lack morphological synapomorphies. Thus, a split between the two taxa must have occurred in deep evolutionary time, which raises the possibility of finding transitional forms in the fossil record. Results Here we describe a new genus and species, Primotrapa weichangensis Y. Li et C.-S. Li (Lythraceae s.l.: Trapoideae), based on three-dimensionally preserved floral cups, fruits, and seeds from the early Miocene of Weichang County, Hebei Province, China. Primotrapa is characterized by a shallow, saucer-shaped floral cup, four distally barbellate sepals, four intersepal appendages alternating with the sepals at the rim of cup, a superior to basally inferior ovary, a fusiform or ovoid, one-seeded fruit with a ribbed surface, and a long persistent peduncle. Two fossil species of Hemitrapa are proposed as new combinations of Primotrapa, namely P. alpina (T. Su et Z.-K. Zhou) Y. Li et C.-S. Li comb. nov. and P. pomelii (Boulay) Y. Li et C.-S. Li comb. nov. Our phylogenetic analysis based on fifteen flower and fruit characters supports the placement of Primotrapa, Hemitrapa and Trapa in a monophyletic clade, which comprise subfamily Trapoideae. The phylogenetic analysis places Primotrapa at the base of Trapoideae. Conclusions In view of its superior ovary, which is a plesiomorphic character of Lythraceae s.l., the newly recognized genus Primotrapa and its three species likely represent transitional forms that bridge the evolutionary gap between the basal taxa of Lythraceae s.l., i.e. Lythrum, and the highly derived taxon Trapa.

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The study of the forest in rainy environments of the Dominican Republic reveals the presence of four types of vegetation formations, clearly differentiated from each other in terms of their floristic and biogeographical composition, and also significantly different from the rainforests of Cuba. This leads us to propose two new alliances and four plant associations located in northern mountain areas exposed to moisture-laden winds from the Atlantic: All. Rondeletio ochraceae - Clusion roseae (Ass. Cyatheo furfuracei - Prestoetum motanae ; Ass. Ormosio krugii - Prestoetum montanae ); and All. Rondeletio ochraceae - Didymopanion tremuli (Ass. Hyeronimo montanae - Magnolietum pallescentis ; Hyeronimo dominguensis - Magnolietum hamorii ). We pay special attention to the description of cloud forest types, since they have a high rate of endemic species, and therefore there are endemic habitats, which need special protective actions. Therefore, we apply the Shannon diversity index to characteristic, companion, non-endemic, and endemic species. As result, the association Ormosio krugii - Prestoetum montanae has a Shannon_T = 2.4 and a value of Shannon_E = 0, whereas the other 3 associations have a better conservation status with Shannon values in all cases > 0: This is due to a worse conservation status of the Eastern Cordillera, in comparison with the Central Cordillera and Sierra de Bhaoruco. Due to human activity, some areas are very poorly conserved, as evidenced by the diversity index and the presence of endemic tree and plant elements. The worst conserved in terms of the relationship between characteristic plants vegetation (cloud forest) in areas with high rainfall are in the Dominican Republic, along with its floristic diversity and state of conservation. This study has made it possible to significantly increase the botanical knowledge of this important habitat.

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Three new species of oribatid mites of the family Oppiidae (Oribatida, Oppioidea), belonging to the genera/subgenera Tripiloppia Hammer, 1968 and Lanceoppia (Baioppia) Luxton, 1985, are described from Central Otago, South Island, New Zealand. Tripiloppia frigida sp. nov. is morphologically similar to T. dalenii Hammer, 1968, but differs from the latter by the lanceolate bothridial setae, five pairs of genital setae, and trapezoid anterior notogastral protrusion. Tripiloppia alpina sp. nov. is morphologically similar to T. frigida sp. nov., but differs from the latter by the short, diagonal costulae, strong teeth in humeral regions, barbed lamellar setae, and interlamellar setae shorter than rostral setae. Lanceoppia (Baioppia) trapezoides sp. nov. is morphologically similar to L. (B.) moritzi Hammer, 1968, but differs from the latter by the larger body length, presence of notogastral setae c, and long interlamellar setae. The taxonomic status of the genus Autoppia Golosova & Karppinen, 1983 and systematic placement of Autoppia algicola Golosova & Karppinen, 1983 are discussed, resulting in the following taxonomic proposals: Tripiloppia Hammer, 1968 (=Autoppia Golosova & Karppinen, 1983 syn. nov.); Tripiloppia algicola (Golosova & Karppinen, 1983) comb. nov. The identification keys to known species of Tripiloppia and Lanceoppia (Baioppia) are given.

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The Cuban species of Calisto are reviewed based on the morphology of adult and immature stages, as well as DNA sequences of six genes (COI, EF1α, wingless, GAPDH, RpS5, CAD). A new species, Calisto occultasp. n., is described from the northeastern Cuban mountains. Calisto smintheus Bates, 1935 and Calisto bruneri, Michener 1949 are revised and revalidated. A new status, the species level, is proposed for Calisto brochei, Torre 1973, Calisto muripetens, Bates 1939 and Calisto bradleyi, Munroe 1950. The immature stages of Calisto smintheus, Calisto brochei,and Calisto occulta are described for the first time, and those of Calisto herophile, Hübner 1823 are redescribed. Useful morphological characters for adults are the shape and conspicuousness of androconial patch, the number and relative size of white dots on underside of hindwing, the shape of aedeagus, the shape of digitiform projection of genitalia valve, the shape and relative size of tegumen and uncus, the relative size of female genitalia, the height of sterigmal ring dorsal crown of the latter, and the relative size of corpus bursae and ductus bursae. For the immature stages, the most important characters are the color pattern of head capsule, the number and width of longitudinal lines of body, in the larvae; and the color pattern and the absence or presence of dorsal ridges on the abdomen of pupae. The phylogenetic relationships between the Cuban Calisto species are quite robust and well-supported; however, conflict between mitochondrial and nuclear datasets was detected in Calisto brochei, Calisto muripetens and to a lesser degree in Calisto bradleyi.

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delta 6-fatty acid desaturase is the rate-limiting enzyme of the desaturation of linoleic acid in the production of an essential fatty acid, gamma-linolenic acid. The 1.4 kb fragment in plasmid pTMACL6 encoding delta 6-fatty acid desaturase from Mortieralla alpina ATCC16266 was subcloned into the yeast-E. coli shuttle vector pYES2.0, thus an expression recombinant plasmid pYMAD6 containing target gene was constructed and obtained in the SC-Ura media. The pYMAD6 was introduced into defective mutant INCSc1 of Saccharomyces cerevisiae by LiAc method. When linoleic acid was provided as an exogenous substrate to the yeast cultures expressing delta 6-fatty acid desaturase activity under appropriate media and temperature condition, the level of gamma-linolenic acid reached 31.6% of the total yeast fatty acids by GC-MS detecting, which is the highest report of delta 6-fatty-acid desaturase gene in S. cerevisiae.

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