Unequal Lobes Research Articles

Bazzania calypogeoides (Marchantiophyta)—a peculiar new taxon from Eastern Hengduan (China)

Bazzania calypogeoides is described from several localities on the eastern edge of the Hengduan mountain system in Sino-Himalaya. The species is characterized by shallowly emarginate underleaves, strongly convex leaves, curved to the ventral side and with a very short sinus resulting in two unequal lobes. The position of the species was assessed using morphological and molecular genetic analyses. A morphologically similar species, B. wooroonooran, is known from Australasia and eastern Melanesia, but differs in several features. A description of the species, illustrations and discussions on the ecology and geography of the new taxon are provided.

Additional morphological characters of the nematode Capillostrongyloides fritschi (Travassos, 1914) Moravec, 1982 (Nematoda: Capillaridae) from Bagrus spp. (Bagridae) inhabiting Damietta Branch of the River Nile, Egypt with a special reference to evaginated cirrus

The catfish Bagrus bajad (Forsskål) and B. docmak (Forsskål) (Siluriformes: Bagridae) are well distributed in the River Nile and have an economic value with good marketing and use in aquaculture. Collected specimens of Capillostrongyloides fritschi (Travassos 1914) were redescribed using a phase-contrast microscope and scanning electron microscope. The most remarkable finding was the unique structure of the evaginated cirrus, being composed of a proximal long tube, a middle spherical bulb packed with mature spermatozoa, and a distal funnel-shaped structure. All regions of the cirrus are provided with longitudinal and transverse muscles and covered with transverse cuticular folds. The mechanism of cirrus emergence was discussed based on available musculature data. Other important findings are the short stylet of the mouth, the two lateral oral lobes, 6-10 buried cephalic papillae and the bacillary bands that lack elevations. Stichosome is formed of 35-44 stichocytes that were differentiated into black and white forms, each containing dense granules and translucent vacuoles. The intestine showed a convoluted part at its anterior region. The vulvar lips are slightly elevated, many mature eggs are cleaved, and their shells are 3-layered. The anus was found in a groove bounded by two unequal lobes.

Rational enzyme design for controlled functionalization of acetylated xylan for cell-free polymer biosynthesis

Xylan O-acetyltransferase 1 (XOAT1) is involved in O-acetylating the backbone of hemicellulose xylan. Recent structural analysis of XOAT1 showed two unequal lobes forming a cleft that is predicted to accommodate and position xylan acceptors into proximity with the catalytic triad. Here, we used docking and molecular dynamics simulations to investigate the optimal orientation of xylan in the binding cleft of XOAT1 and identify putative key residues (Gln445 and Arg444 on Minor lobe & Asn312, Met311 and Asp403 on Major lobe) involved in substrate interactions. Site-directed mutagenesis coupled with biochemical analyses revealed the major lobe of XOAT1 is important for xylan binding. Mutation of single key residues yielded XOAT1 variants with various enzymatic efficiencies that are applicable to one-pot synthesis of xylan polymers with different degrees of O-acetylation. Taken together, our results demonstrate the effectiveness of computational modeling in guiding enzyme engineering aimed at modulating xylan and redesigning plant cell walls.

Piper Ribesioides Wall., a Newly Recorded Species for the Flora of Vietnam

We here reported a newly recorded Piper species for the flora of Vietnam, namely Piper ribesioides Wall. (Piperaceae). This species is most morphologically similar to P. politifolium C.DC. by sharing glabrous plants and fruits with a stipe, but it differs from the latter having a monoecious habit (vs. dioecious), stamens 4 (vs. 2), and a cordate leaf base with equal or subequal lobes (vs. oblique with unequal lobes). Descriptions, illustrations, information on ecology, and taxonomic notes of the species is provided.

A New Species and Lectotypification in Ruellia (Acanthaceae) from the Southeastern Atlantic Forest, Brazil

Abstract—Ruellia capotyra is described as a new species of Acanthaceae from the Atlantic Forest of Brazil, occurring in the states of Rio de Janeiro and Minas Gerais. This species was discovered during fieldwork in a natural forested area, and further details regarding its ecology and broader geographical distribution were clarified through the study of existing herbarium collections. Ruellia capotyra is a subshrub characterized by long-petiolate leaves, long-pedunculate, axillary, and compound dichasia, and rose-colored, long, and curved corollas. It differs from other species of Ruellia by its quadrangular, glabrescent branches and rachises, the absence of bracteoles, calyces with subulate, unequal lobes, and sparse, long-glandular trichomes. The new species is described and illustrated. Diagnostic characters and comments regarding its geographical distribution, phenology, and taxonomy are presented. Ruellia capotyra is compared with other species previously described in the genus and its infrageneric position is discussed. One of these species is Ruellia subsessilis, for which a lectotype is here designated and its authority corrected. An informal IUCN conservation assessment of the new species indicated that it should be considered as a threatened species, further highlighting the conservation significance of the Atlantic Forest as a whole.

Taxonomic notes on the genus Hydrobaenus with description of H. simferopolus sp. nov. from Crimea (Diptera: Chironomidae)

Abstract A new species of the genus Hydro baenus Fries, 1830, H. simferopolus sp. nov. (Diptera: Chironomidae: Orthocladiinae), is described based on adult male collected in the Crimean Penisula (Ukraine). Main distinguishing characters are: anal point cup-shaped with a small nose-like apex; virga composed of 3 strong equal spines; inferior volsella consisting of 2 lobes (proximal one broadly planned and covered with curved setae, distal one large nose-like and bare). A new combination of Parorthocladius korneyevi Baranov, 2011 for H. korneyevi (Baranov, 2011) comb. nov. is provided with additional differentiating characters found in male adult including: tergite IX with a median dorsal crest; anal point long, drop-like, covered with setae and ending with thumb-shaped apex; virga composed of 6–8 subequal thin long spines; inferior volsella with 2 unequal lobes (proximal one spherical and much larger); gonostylus massively bulbous and densely covered with long and short setae, crista dorsalis consists of a subapical strong tooth-like, smooth and orally projecting ridge. The male adults of both H. dentistylus Moubayed, 1985 and H. lugubris Fries, 1830 are also illustrated, diagnosed and shortly redescribed with some main distinguishing and supplementary characters. Remarks and comments on the taxonomic position, ecology and geographical distribution of the four Hydrobaenus species are given.

Anatomie Et Histologie De L’hépatopancréas Chez La Femelle Du Poisson, Chloroscombrus Chrysurusde Linnaeus, 1766 (Carangidae) En Côte d’Ivoire

Chloroscombrus chrysurus is a pelagic fish species that belongs to the Carangidae family. It has a fairly high level of exploitation in Côte d'Ivoire. This paper focuses on the study of the maturity scale, the differentiation, and the histology of hepatopancreas. The methodological approach consisted of a macroscopic description of the hepatopancreas according to the six stages of sexual maturity. The microscopic study consisted of fixing the hepatopancreas, dehydrating them, impregnating them, including them, and making the sections that will be stained for optical microscopic observation. Macroscopic analysis has established six stages of sexual maturity in the species during which the growth and differentiation of hepatopancreas occur. From the juvenile to the adult stage, the size and color of the hepatopancreas vary. On the other hand, its aspect and shape remain unchanged. The hepatopancreas consists of two unequal lobes. The left hepatic lobe is always more developed than the right. On the microscopical level, among the female gender, the hepatopancreas is a mixed organ which constituted the hepatic parenchyme and pancreas. The pancreas differs in the hepatic parenchyma which is composed mainly of polygonal hepatocytes and blood vessels. The hepatocytes are arranged in sinusoidal cords around the capillaries. The pancreas is composed of islets of Langerhans (endocrine pancreas) and serous acini Pancreatic (exocrine pancreas). Both structures progressively invade the hepatic parenchyma. The hepatopancreas is an essential organ in the physiology of fish.

Anatomie Et Histologie De L’hepatopancreas Chez Le Male Du Poisson Brachydeuterus Auritus (Haemulidae, Valenciennes, 1831) En Cote D’ivoire

Brachydeuterus auritus is a fish species with a high level of exploitation potential in Côte d'ivoire. The following study is based upon a maturity ladder and the discrimination of the hepatopancreas. The methodological approach consisted of a macroscopic description of the hepatopancreas according to the five stages of sexual maturity. The microscopic study consisted of fixing the hepatopancreas, dehydrating, impregnating, including it, making cuts that are colored for observation. At the macroscopic level, the hepatopancreas is made of two unequal lobes. The organ has a colouring as well as a vascularization varying in terms of the species development stages. At the microscopic level among the males, the hepatopancreas is a mixed organ made of the liver and the pancreas. The hepatopancreatic parenchyma is an homogeneous tissue made of hematocytes which are polygonal cells. In addition, we can find hematopoietic tissues in the parenchyma and melanomacrophages centers located near the blood vessels and the biliary tracts. The melanomacrophages centers are formed with cells accumulating pigment cells. Inside the organ, the pancreas is discriminated centripally and constituted of exocrine cells and Langerhans islets. The physiology of the two entities (liver and pancreas) will establish the organ's physiology. Hepatopancreas is involved in reproduction, digestion and defence. It exists as an organ that controls many functions and plays an important part in the physiology of fish in anabolism and catabolism.

A new species of Standleya (Rubiaceae, Coussareeae) with a new record for Bahia, Brazil

Standleya glomerulata, a new species and a first record for the semiarid region of Bahia, Brazil, is described and illustrated. It differs from all other known species of the genus by its prostrate decumbent and reptant habit, glomerulate sessile inflorescences, and a calyx with two unequal lobes. S. prostrata has a similar habit, but can be distinguished by the pedunculate inflorescences and a calyx with four equal lobes. The new species is known from only a few localities in two protected areas and must therefore be considered threatened.

Dinurus ivanosi sp. nov. (Digenea: Hemiuridae) from the stomach of dolphin fish, Coryphaena hippurus, caught off the Kerala Coast, India.

A new species of stomach fluke, Dinurus ivanosi (sp. nov.), was recovered from the dolphin fish, Coryphaena hippurus, off the Kerala Coast, India. It is similar to other Dinurus species in the plicated prosoma, trilobed seminal vesicle and seven vitellaria, but differs from them in the length of the pharynx, unequal lobes of the seminal vesicle and unequal size of the testes. The most important diagnostic features of the new species are the general shape and proportions of the body, the position of the oral sucker, elongated pharynx, small distal lobe of the seminal vesicle, and larger anterior testis, smaller egg size, short and slender vitellaria and the limited extent of the vitelline field.

Directional sensitivity of tuberous electroreceptors: polarity preferences and frequency tuning

This paper examines the directionality of tuberous electroreceptor responses and relates them to a polarity bias seen for passive electrolocation by electric fish (Hypopomus). We recorded from Burst Duration Coders (BDCs) while stimulating with 1 kHz single period sine waves with electric fields oriented horizontally in different directions. Electroreceptors have figure-8 directional sensitivity profiles with two, usually unequal lobes of sensitivity separated by 180 degrees. For most units the larger lobe points inward, while for a few, the lobes are symmetrical or the larger lobe points outward. The differences correlate with differences in frequency tuning of the receptors. We can alter, and even reverse, the directional asymmetry of a single unit by changing the frequency of the stimulus. Two general response profiles results, with two corresponding classes of tuning curves. The degree of asymmetries and the effects of stimulus frequency and of tuning can be modeled with a linear/non-linear/linear cascade filter. The behavioral preference for approaching the head end (+) of an electrode is difficult to understand in light of the asymmetry of responses we report for amplitude-coding BDCs but can be understood by reference to the time-coding Pulse Marker (PM) receptors.

A New Species of Aegiphila (Verbenaceae) from Colombia

A new species, Aegiphila narinensis (Verbenaceae), from La Planada Reserve, Colombia, is described, and its affinities are discussed. The new species has mucronate calyx lobes, and the corolla is larger than in any other species in the genus and has a curved tube. This name is needed to complete the botanical list of plants collected at La Planada Reserve being compiled by Olga de Benavides and Alwyn Gentry. Aegiphila is a genus of about 160 species of shrubs and trees found from Cuba and Mexico through the West Indies and Central America to Peru and northern Argentina. About 40 species are found in Colombia (Moldenke, 1980), 10 of which are endemic, including this new one. Aegiphila narinensis Rueda, sp. nov. TYPE: Colombia. Nariiio: La Planada Reserve, near Ricaurte, 1,800 m, 01?05'N, 78?01'W, 21 Dec. 1987 (fl), Gentry, Benavides & Keating 59648 (holotype, MO; isotype, PSO not seen). Figure 1. Suffrutex 0.5-1 m altus, glabrus. Folia petiolata; laminis subtus punctatis, ellipticis, 14-18 cm longis x 8-10 cm latis, chartaceis, 6-8 venis secundariis. Inflorescentiae 3.5-6 cm longae x 3-5 cm latae; bracteis 2-4 mm longis; pedicellis 1.5-3 cm longis. Flos lobis calycinis 13 mm longis mucronatis; corolla hypocrateriformi alba, glabra, tubo arcuato, 2.5-3 cm longo, lobis 1.5-2 cm longis, inaequalibus. Subshrub 0.5-1 m tall; branches tetragonal or subterete, sparsely pilose, glabrescent. Leaves decussate-opposite; blade elliptic, acute to acuminate at apex, acute to cuneate at base, 14-18 x 8-10 cm, chartaceous, sparsely hirsute, both laminar surfaces glabrous, lower surface punctate; venation eucamptodromous to weakly brochidodromous, the midrib slightly elevated adaxially, prominently elevated abaxially, secondary veins 6-8 on each side of costa, at an angle of 45? with the costa, impressed adaxially and elevated abaxially, arcuate-ascending, with well-marked minor veins; margins entire to slightly sinuate; petioles 0.8-1 cm long. Inflorescences cymose, axillary, few-flowered, 3.5-6 x 35 cm; peduncles 1.5-2.5 cm long, bracts linear, 24 mm long; pedicels 1.5-3 mm long; peduncle, bracts, and pedicels glabrous. Calyx glabrous, the lobes triangular, mucronate, 1-3 mm long; corolla white, glabrous, salverform, the tube curved, 2.53 cm long, limb lobed, 1.5-2.5 cm wide, the lobes obovate, 1.5-2 cm long, unequal; stamens 4, attached to the throat of the corolla, equal, the filaments filiform, ca. 2 mm long, slightly surpassing the corolla mouth, the anthers oblong; ovary globose, the style filiform, reaching to 3-5 mm below stamen insertion, 1.5 cm long, stigma bifid, the branches 1 mm long. Fruit not seen. Aegiphila narinensis is distinguished from other species in the genus by having mucronate calyx lobes and a curved corolla tube about 3 cm long. The corolla is larger than in any of the other species, with unequal lobes 1.5-2 cm long. This species resembles the complex of closely related and largeflowered species formed by Aegiphila costaricensis Mold., from Central America, and A. haughtii Mold., Clerodendrum tessmanni Mold., and C. ulei Hayek from South America, as discussed by Nash & Nee (1984). However, elements of this group have straight corolla tubes of less than 25 mm long, with lobes more or less equal, whereas A. narinensis has a curved corolla tube of more than 25 mm in length, and unequal lobes. In addition, the species of Clerodendrum in this group have stamens that are long exserted, whereas A narensis has stamens that only slightly surpass the corolla mouth. The type was collected at 1,800 m elevation, in the cloud forest of the La Planada Reserve, in the state of Nariio, after which the species is named. This area is famous for its high biological endemism (Terborgh & Winter, 1982), to which this distinctive new species adds yet another example. Acknowledgments. I thank John Myers for the excellent illustration, and William G. D'Arcy, Alwyn NOVON 2: 167-168. 1992. This content downloaded from 207.46.13.64 on Sat, 03 Sep 2016 04:41:30 UTC All use subject to http://about.jstor.org/terms

Apical Dominance in Marchantia: Correlative Inhibition of Neighbor Lobe Growth

Growth factors may control the development of the typical fan-shaped appearance of Marchantia polymorpha in ways similar to the control of apical dominance in higher plants In Marchantia, apical dominance is characterized by the greater growth of one lobe compared with its neighboring lobe Two neighbor lobes develop from two apical notches or growing regions of a previously established lobe. The lobe which grows larger is invariably the one nearer the midrib of the growing thallus If the notches that will eventually give rise to separate unequal lobes are separated by a cut at an early stage of lobe growth, the smaller lobe is released from inhibition and grows to a size equal to the dominant lobe Indole-3-acetic acid (IAA), which is involved in maintaining apical dominance in higher plants, applied to the smaller lobe after cutting reestablishes the inhibition. It also increases the inhibition of the smaller lobe when applied to it on an intact plant. The growth of the dominant lobe is neither inhibited nor promoted by IAA We suggest that the type of neighbor lobe dominance in Marchantia resulting in its typical fan-shaped growth habit is maintained by auxin through a differential sensitivity of the two neighbors to auxin inhibition

Morphology of the Gynobase in Mertensia

The conformation of the ring-like disc or gynobase surrounding the gynoecium varies greatly among the genera of Boraginaceae. The morphology of the gynobase ha's been taken for granted by most systematists, and has been used descriptively in connection with description of nutlet attachment. No morphological or evolutionary significance has been attached to the gynobase. In other families, anatomical and morphological studies have demonstrated that many discs, nuptial nectaries, and floral squamellae may be interpreted in terms of the other appendages of the flower. For example, it is believed that the sheathing disc about the carpel in many Leguminosae represents an abortive set of stamens.1 Structures adjacent to the gynoecium which have been observed in many Apocynaceae are interpreted as carpellodes.2 The heteromorphic nature of the gynobase of Mertensia is apparent on gross examination (Figs. 15, 16). The four unequal lobes of the gynobase alternate with the four nutlets of the pistil. Opposed to the carpels are two small obtusely triangular pointed lobes. Alternated with the carpels are the two large lobes which equal or surpass the nutlets in size. For a better understanding of the morphology of the gynobase it is necessary to describe briefly the anatomy of the flower in Mertensia. The vascular anatomy of the flower is not especially complicated in Mertensia. In most respects the description given here applies to other members of the Boraginaceae which I have examined (Figs. 1-13). The pedicel contains a circle of ten strands, alternately large and small (Fig. 1). The five smaller traces swing outward and upward to supply the sepals (Fig. 4). These strands split radially into 3 parts after they leave the stele. Lateral strands of adjacent calyx lobes do not fuse. The sepal gaps close, and then the petal and stamen traces begin to depart (Fig. 5). Each stamen receives one trace. There are five petal traces, and these split radially into three members after leaving the stele. The petal and stamien trace gaps close and the stele becomes provascular except for the strands which are to supply the carpels (Fig. 7). Each carpel is provided with three traces. The two ventrals of each carpel swing inward and upward toward the center of the flower, each eventually ascending through the placenta into the funiculus (Figs. 10-12). The dorsal bundle pursues a devious upward course which leads into the style. The median lateral bundles seen in the nutlet walls apparently arise from the placental bundles, curve upward into the wall of the nutlet and then gradually die out.

Development of Floral Organs of the Soy Bean

1. The mature flower of the soy bean consists of a calyx tube with five unequal lobes, five distinct petals, ten stamens (nine united and one free), and a single carpel. Both unicellular and multicellular trichomes are found on the calyx and pistil. 2. The flower primordium appears first as a protuberance in the axil of a bract. The order of emergence of the floral organs is sepals, petals, outer cycle of stamens, inner cycle of stamens, pistil. The order of emergence within each cycle is from the anterior to the posterior side of the receptacle. 3. Development of the petals is slow at first, but later becomes rapid. The stamens are free at first; later nine become united leaving one of the inner cycle free. 4. The one to four campylotropous ovules develop simultaneously, and the micropylar end is directed toward the distal end of the ovary.