Taxonomic history, comparative morphology, and variation in Astrophytum myriostigma and its subspecies tulense (Cactaceae)

Astrophytum myriostigma subsp. myriostigma and subsp. tulense are distinguished by both vegetative and reproductive characters. The stem of the nominotypical subspecies is broad and depressed becoming broadly cylindrical in age, reaching a known maximum height of ca. 52 cm. In subsp. tulense, the stem is relatively slen-der and columnar and can reach a maximum height of ca. 90 cm. Both taxa show variation in the angle and profile of the ribs. In the nominotypical subspecies, the ribs are usually obtuse with a rounded or angular profile, or moderately acute with an angular profile. In subsp. tulense, the ribs are typically moderately to very acute with an angular profile. There are exceptions to these generalities. Both taxa have a modal number of five ribs, and both have the tendency to insert additional ribs with age, although the tendency seems more pronounced in subsp. tulense. The flower of the nominotypical subspecies differs from that of subsp. tulense in having a significantly larger mean perianth diameter (P <= 0.01), a significantly higher mean number of stigma lobes (P <= 0.05), and more tepal rows (3–5 vs. 1–3). The color of the tepals is pale yellow to whitish yellow in subsp. tulense, but brighter yellow or golden yellow in the nominotypical subspecies. The seeds of the nominotypical subspecies are significantly larger (P <= 0.01) than the seeds of subsp. tulense. Morphological variation was studied in nine populations of the subsp. myriostigma and six populations of the subsp. tulense. The nominotypical subspecies displays rib angle and rib profile differences among individual plants within a population. Plants with a depressed stem and obtuse, rounded ribs are predominant at some localities. At other localities, plants with more moderately acute, angular ribs are predominant, or at least common. Populations of subsp. tulense show individual variation in stem morphology. The stem varies from attenuated (tapered) to non-attenuated and from relatively slender (diameter ca. 20% of height) to relatively broad (diameter ca. 77% of height). The plants from near Mama León and adjacent localities in Tamaulipas, have very robust stems and are the least typical of the columnar subspecies. The rela-tionships of this population to other columnar populations warrant further study. The population near Las Tablas, San Luis Potosí, shows considerable variation in the stem and rib morphology. Some plants resemble the nominotypical subspecies whereas others are similar morphologically to subsp. tulense. The perianth diameter is intermediate between those of the two subspecies. The evidence suggests that this is an area of past or ongoing hybridization between the two taxa; the question of hybridization warrants further investigation. Attenuated and non-attenuated stems are the result of differential rates of vertical and lateral growth due to cellular activity in the apical and lateral meristems, respectively. The attenuated (tapered) stem is produced by a gradually increasing lateral growth rate which remains slower than the vertical rate. A non-attenuated stem is produced by the lateral growth rate exceeding the vertical rate early in development, then stabilizing at some point and not surpassing the vertical rate.

Reproductive phenological shifts and other phylogenetic trait changes in the Arbutoideae (Ericaceae) in the context of drought, seed predation, and fire.

Phenology is an ecologically critical attribute that commonly is coordinated with other plant traits. Phenological shifts may be the result of evolutionary adjustments to persistently new conditions, or transitory, varying with annual flux in abiotic conditions. In summer-dry, fire-prone Mediterranean-climates, for example, many plant lineages have historically migrated from forests to more arid shrublands resulting in adaptive trait changes. These shifts in habitat abiotic conditions and biotic interactions influence morphology of flowers and fruits and will interact with phenological timing. The Arbutoideae (Ericaceae) is one lineage that illustrates such modifications, with fruit characters evolving among genera from fleshy to dry fruit, thin to stony endocarps, and bird to rodent dispersal, among other changes. We scored herbarium collections and used ancestral trait analysis to determine phenological shifts among the five Arbutoid genera found in semi-arid climates. Our objective was to determine if phenology shifts with the phylogenetic transition to different reproductive characters. Our results indicate that phenological shifts began with some traits, like the development of a stony endocarp or dry fruits, but not with all significant trait changes. We conclude that early phenological shifts correlating with some reproductive traits were permissive for the transition to other later character changes.

Astragalus dinawarii (section Incani), a New Species from the Talesh Mountains, Northwestern Iran

Astragalus dinawarii Bidarlord & F. Ghahrem. (Fabaceae) is described as a new species based on material collected on the Talesh Mountains, northwestern Iran. This species belongs to a large bifurcating section, Astragalus L. sect. Incani DC. Morphologically, it is close to A. bukanensis Maassoumi & Podlech, A. diversus Podlech & Maassoumi, and A. dilutuloides Maassoumi, F. Ghahrem. & Bagheri, sharing several densely hairy leaflets and stipitate legumes. This species is easily distinguished from similar species by a set of both vegetative and reproductive characters such as size, shape, number of leaflets, shorter calyx, and longer legume stipe. A detailed description and comparisons with similar taxa, color images, distribution and habitat, and conservation status of the new species are provided.

KERAGAAN BIOREPRODUKSI TIGA GENERASI IKAN TAMBAKAN (Helostoma temminckii Cuvier, 1829)

Ikan tambakan merupakan ikan lokal yang potensial menjadi ikan budidaya. Salah satu proses penting dalam budidaya adalah aspek reproduksi. Penelitian untuk mengetahui karakteristik bioreproduksi tiga generasi ikan tambakan hasil kegiatan domes‘tikasi di Balai Riset Perikanan Budidaya Air Tawar dan Penyuluhan Perikanan, Bogor. Pengujian dilakukan untuk mengetahui posisi gonad, fekunditas, derajat pembuahan, dan derajat penetasan ikan tambakan generasi yang berbeda. Hasil yang diperoleh menunjukkan posisi gonad vertikal mengarah ke tulang belakang, di bagian ujung melengkung ke arah depan dan gonad berada di belakang urogenital. Fekunditas telur/gram bobot ikan yang dihasilkan tidak berbeda antar generasi dengan jumlah berkisar antara 76 ± 13 sampai 83 ± 14 butir. Persentase telur terbuahi dan telur menetas antar generasi juga tidak berbeda, masing-masing berkisar antara antara 70,6 ± 16,05 sampai 92,9 ± 10,88%; dan 51,3 ± 16,64 sampai 74,3 ± 10,32%. Jumlah larva yang dihasilkan juga tidak berbeda nyata antar generasi, berurutan dari yang kecil ke besar G-0 (38,7 ± 10,72 butir/g bobot ikan), G-1 (45,3 ± 5,20 butir/g bobot ikan), dan G-2 (55,7 ± 7,75 butir/g bobot ikan). Program domestikasi ikan tambakan tidak mempengaruhi karakter reproduksi ikan antar generasi. Keragaman karakter reproduksi antar generasi masih tinggi. Pembentukan generasi selanjutnya perlu dipertahankan, sehingga dapat digunakan sebagai ikan budidaya baru.Kissing gourami is an Indonesian local fish species that has the potential to be developed as a farmed fish. However, the current domestication stage of the fish still requires further information regarding its bio reproduction. The research on determining the bioreproductive characteristics of three generations of kissing gourami has been carried out at the Research Institute of Freshwater Aquaculture and Fisheries Extensions, Bogor. This research aimed to determine the gonad position, gonad maturity index, and fecundity between the kissing gourami generations. The results showed that the gonads were positioned vertically towards the backbone, curved ends towards the front and located behind the urogenital. The fecundity of produced eggs/gram body weight of fish did not differ between generations and ranged between 76 ± 13–83 ± 14 eggs. The percentages of fertilized eggs and hatched eggs between generations did not differ and ranged between 70.6 ± 16.05–92.9 ± 10.88% and 51.3 ± 16.64–74.3 ± 10.32%, respectively. The number of produced larvae was also not significantly different between generations where G-0 has the lowest number (38.7 ± 10.72 eggs/g fish weight), followed by G-1 (45.3 ± 5.20 eggs/g fish weight) and G-2 has the highest number of produced larvae (55.7 ± 7.75 eggs/g fish weight). The aquaculture domestication program does not affect the reproductive character of fish between generations. The diversity of reproductive characters between generations is still high. The formation of the next generation needs to be maintained, so that it can be used as a new cultured fish.

Novitates neocaledonicae. XIII. Taxonomy and nomenclature of the genus Xyris (Xyridaceae, Poales) in New Caledonia, with description of a new species

Three endemic species of Xyris (Xyridaceae, Poales) are currently recognized in New Caledonia. A recent multivariate analysis of 18 morphological characters based on 129 specimens of Xyris from New Caledonia, supported by 10 anatomical and micromorphological observations, suggested that three species should be recognized in the New Caledonian archipelago. However, the three published names did not correspond to the three entities identified via the multivariate analyses. The results showed that Xyris neocaledonia Rendle was morphologically distinct but requires lectotypification, Xyris guillauminii Conert was indistinct from X. pancheri Rendle, and that a new morphologically distinct species required description. We therefore propose to clarify the taxonomy of the genus for New Caledonia, by designating a lectotype, making this synonymy and describing the new species. The new species, Xyris desquamatus J.R.Morel & Munzinger, sp. nov., has the remarkable feature of leaves that are shed as the plant senesces, and is reflected in the specific epithet for this new species. Line drawings are provided for the new species, along with colour photos for the three New Caledonian Xyris species and a distribution map. Three identification keys are provided, the first based on vegetative characters, the second on reproductive characters and the third on anatomical features of the leaf. Xyris desquamatus is preliminarily assigned an IUCN risk of extinction assessment of vulnerable.

Influence of defoliation during reproductive stage on seed yield in uniculm mungbean plants

An experiment was conducted at the pot yard of Bangladesh Institute of Nuclear Agriculture, Mymensingh during the period from February to May 2018 to investigate the effect of defoliations on morphological characters, yield attributes and yield of uniculm mungbean plant. The experiment comprised of nine levels of defoliation viz., control, 2, 3, 4, 5 leaves removal from base and 2, 3, 4 and 5 leaves removal from top out of 7 leaves during flowering start phase. The morpho-physiological characters such as plant height, stem diameter, leaf area and total dry mass plant-1 and number of racemes, reproductive characters such as rachis length and diameter, number of flowers plant-1 and reproductive efficiency, yield contributing characters such as number of pods plant-1, pod length, number of seeds pod-1, single pod and 100-seed weight and seed yield decreased with increasing defoliation both from base and top except basal 2 leaves defoliation. The above parameters increased over control in basal 2 leaves defoliation. The decrement due to defoliation was greater in top defoliated plants than the corresponding basal defoliated ones indicating upper leaves contributes more assimilate to the sink than the basal leaves. The highest morpho-physiological parameters, reproductive characters and yield contributing characters observed in basal 2 leaves defoliated plants which resulted the highest seed yield (5.75 g plant-1) followed by control (5.49 g plant-1). The lowest morpho-physiological parameters, reproductive and yield contributing characters recorded in top 5 defoliated plants and produced the lowest seed yield (1.21 g plant-1). These results suggest that uniculm mungbean plant tolerate basal 2 leaves loss in the canopy during reproductive stage.

Phyllanthus chacoensis (Phyllanthaceae): new record for the Brazilian Amazon and its lectotypification

ABSTRACT The first record of Phyllanthus chacoensis for the Brazilian Amazon is presented, based on a specimen from Rondônia state. The species can be recognized by its cauliflorous inflorescence, staminate and pistillate flowers with 4 sepals, devoid of a floral disk, 4 stamens, 2-carpellary ovary, drupaceous, ellipsoidal fruits, with one seed per locule. The species was previously known only from the central-western and northeastern regions of the Caatinga and Pantanal domains in Brazil. We provide a list of synonyms, a detailed description, an updated geographic distribution map in Brazil, data on habitat and conservation status, illustrations of its reproductive characters, and detailed photographs. We also propose a lectotype for the species.