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Authors: Sabine Rosner and Hugh Morris

Summary

Lenticels can be defined as pores that are the entrance of a continuous aeration system from the atmosphere via the living bark to the secondary xylem in the otherwise protective layers of the periderm. Most work on lenticels has had an anatomical focus but the structure-function relationships of lenticels still remain poorly understood. Gas exchange has been considered the main function of lenticels, analogous to the stomata in leaves. In this perspective review, we introduce novel ideas pertaining to lenticel functions beyond gas exchange. We review studies on lenticel structure, as this knowledge can give information about structure-function relationships. The number of species investigated to-date is low and we provide suggestions for staining techniques for easy categorization of lenticel types. In the follow-up sections we review and bring together new hypotheses on lenticel functioning in the daily “normal operation range”, including regulative mechanisms for gas exchange and crack prevention, the “stress operation range” comprising flooding, drought and recovery from drought and the “emergency operation range”, which includes infestation by insects and pathogens, wounding and bending. We conclude that the significance of dermal tissues and particularly of lenticels for tree survival has so far been overlooked. This review aims to establish a new research discipline called “Phytodermatology”, which will help to fill knowledge gaps regarding tree survival by linking quantitative and qualitative lenticel anatomy to tree hydraulics and biomechanics. A first step into this direction will be to screen more species from a great diversity of biomes for their lenticel structure.

In: IAWA Journal

Abstract

In Mexico, information about ocelots is limited, which hinders the implementation of effective management and conservation measures. The purpose of this research was to provide basic information of population density, relative abundance and home range observed for the species in northwestern Mexico. Systematic sampling was implemented from January to December 2015 using photo-trapping as tool. Fifty-four camera-trap stations (37 double stations) were used, and the resulting grid covered an area of 182 km2. We applied six sampling periods of 59-62 days in each period. Density analysis was based on spatially explicit models and traditional capture-recapture models. The home range was estimated using the minimum convex polygon method. We obtained 135 photographic records of ocelots, of which 17 individuals were identified (five males, four females and eight individuals of undetermined sex). During six study periods, our sampling effort reached 19 710 trap-days. We estimate a capture rate for the study of 6.84 rec./1000 trap-days. The density of ocelots estimated with the Capture module in the MARK program ranged from 1.38 to 2.93 rec./100 km2. The results estimate using the SERC method showed a density of 0.93-3.06 individuals per 100 km2. The ocelots in the Northern Jaguar Reserve (NJR) had an average distribution area of 14.1 km2. The results of this research illustrate the importance of continuing studies of ocelots on the NJR to maintain a long-term viable population for northwestern Mexico.

In: Animal Biology

Abstract

Transcription factor p8 plays an important role in regulating autophagy in Daphnia pulex cells. In this experiment, 19 genes encoding 71, 271 and 117 amino acids, respectively, were obtained by RACE (Rapid Amplification of cDNA Ends). Subsequently, qPCR was used to detect the gene expression of Daphnia pulex genes for p8, ATG5 and ATG8, at different time points and in different reproductive pathways. It was thus found that p8 was significantly expressed only before the natural extrusion of resting eggs. ATG5 and ATG8 were stably expressed at a low level in the “summer eggs” produced parthenogenetically, and significantly expressed in the juvenile fleas. The mRNA expression levels in the sexual reproduction pathway gradually increased, and the mRNA expression levels of ATG5 and ATG8 reached their peaks 36 h after resting egg production, and these were significantly higher than those in other time periods. After the resting eggs are completely formed and naturally extruded, the expression levels of ATG5 and ATG8 are almost undetectable. Therefore, any expression levels of ATG5 and ATG8 can hardly be detected when the resting eggs have completely been formed and naturally discharged. Thus, by preparing Escherichia coli capable of producing p8 dsRNA and feeding Daphnia pulex for RNAi, we found that after interfering with the expression of p8, the expression levels of ATG5 and ATG8 had also decreased. The results may provide a theoretical basis for further exploration of the relationship between the Daphnia pulex gene for p8 and the formation of resting eggs.

In: Crustaceana

A sportfish expert at the El Cheapo Sheepshead Fishing Tournament in Mayport, Florida, 21 February 2015, took a photograph (fig. 1) of the sheepshead, Archosargus probatocephalus (Walbaum, 1792), that won the tournament (M. A. Roffer, pers. comm.). He did so because he had never seen acorn barnacles, Chelonibia testudinaria (Linnaeus, 1758), on a fish previously. He sent the photographs to other fishery people. One ichthyologist, who had also never seen this association, could not find a record of anything similar, either (R. E. Waldner, pers. comm.). He sent the information to us (EHW & LBH) because

In: Crustaceana

Abstract

Two leucosioid crabs, Iphiculus spongiosus Adams & White, 1849 and Tokoyo eburnea (Alcock, 1896), as yet undescribed from Korean waters, were collected by bottom otter trawls. These two species now are the only members of, respectively, the genera Iphiculus and Tokoyo known from Korea. In this article, brief descriptions and illustrations are given for both taxa.

In: Crustaceana

Abstract

An old collection of brachyuran specimens from the Iraqi coast, collected in the last century, was examined. This resulted in four new records from the northwest Persian-Arabian Gulf that could be recognized: the podotreme Lauridromia dehaani (Rathbun, 1923), and the heterotremes Dorippoides nudipes Manning & Holthuis, 1986, Enoplolambrus carenatus (H. Milne Edwards, 1834), and Charybdis (Archias) longicollis Leene, 1938. Lauridromia dehaani is the first record of this species from the northwest of the Persian-Arabian Gulf (Iraq and Kuwait), the other species are widely distributed around the Gulf. The specimens were photographed and diagnosed, and the new records are reported in the present study.

In: Crustaceana

Abstract

Groundnut is an important oilseed crops with high nutritional values. Yield of groundnut is constrained owing to diverse biotic and abiotic factors. Amongst biotic stresses two foremost foliar fungal diseases viz., late leaf spot and rust are universal and sparingly significant. Both conventional and modern breeding methods may be applied for improvement of groundnut. The current investigation was carried out to recognize genetic variability present among different groundnut germplasm with the use of morphological characters and SSR markers with the screening of resistant to leaf spot and rust resistant genotypes. In morphological examination, the analysis of variance divulged highly substantial differences among 48 germplasm lines. Initial screening of Germplasm was tried with the use of 125 SSR markers. But, based on banding pattern, 21 markers were found to be the best and selected for amplification of whole set of genotypes. Out of 21 markers, 16 were found to be highly polymorphic. Highest PIC value (0.8196) was detected for marker S021 representing 81% diversity. SSR Markers viz., PM42, PM204, PM377, S052, S076, S078 and S078 have PIC value more than 0.5, confirms their superiority in detection of polymorphism among studied germplasm lines. UPGMA analysis assemblage all the germplasm lines into three major clusters. Most of the foliar disease resistant genotypes were grouped together with higher genetic resemblance. Polymorphic markers identified in the study may be utilized further for molecular diversity analysis and the identified resistant genotypes may be employed further for the improvement of the crop.

In: Israel Journal of Plant Sciences

Abstract

A new species of Cuapetes, C. canariensis sp. nov., is described on the basis of a single specimen from Tenerife, Canary Islands. This is the first record of a species in the genus Cuapetes from the eastern Atlantic. It belongs to a group of previously exclusively Indo-West Pacific species possessing a supraorbital spine and a distoventral tooth on the merus of the second pereiopods. A morphological comparison with members of this group of species is provided. A molecular analysis based on the mitochondrial 16S gene of available sequences of Cuapetes species and species of related genera reveals its close affinity with Cuapetes amymone.

In: Crustaceana

The marine shrimp genus Brachycarpus, generally inhabiting crevices and caves in reefal habitats, is ecologically distinctive from its close relatives that mostly live in fresh water, estuaries or the marine littoral zone (e.g., Arachnochium, Creaseria, Cryphiops, Macrobrachium, Palaemon) (clade Pal-II, sensu Chow et al., 2020). Morphologically, it possesses biunguiculate ambulatory dactyli that are not developed in related genera but more common in symbiotic lineages (Chow et al., 2021). The genus currently comprises three species, namely the well-known pantropic/temperate B. biunguiculatus (H. Lucas, 1846), the enigmatic Brazilian

In: Crustaceana
Author: Kunihiko Izawa

Abstract

Nothobomolochua aigo sp. nov. is described based on two specimens of the female recovered from the bucco-branchial cavity of the mottled spinefoot, Siganus fuscescens (Houttuyn, 1782), captured by a fixed net at Kuki, Mie Prefecture. The fish was subsequently found in a vessel with formalin solution in which eight species of coastal actinopterygian fishes, including S. fuscescens, all captured by the same fixed net at Kuki, had been fixed and preserved together. The postantennal process and the lateral processes of this species are herein described for the first time for the genus.

In: Crustaceana