Characterization of the species of genus Physa on the basis of typological species concept from Central Punjab

Physids belong to Class Gastropoda; Phylum Mollusca have important position in food web and act as bio indicators, pests and intermediate host. Being resistant these are called cockroaches of malacology. Physid snails were collected from different water bodies of Faisalabad (Punjab) and were identified up to species using morphological markers. The morphometry of the specimens was carried out with the help of a digital Vernier caliper in millimeters (mm) using linear measurement of shell characters. Linear regression analysis of the AL/SW ratio vs AL and SL/SW ratio vs AL indicated that allometric growth exists only in Physa acuta when compared with P.gyrina and P. fontinalis. This study will lead to assess the status of the Physid species in Central Punjab. The Principal component analysis shows that the Component 1 (Shell Length) and component 2 (Shell Width) are the most prolific components and nearly 80 percent of the identification. The distance between P. acuta and P. fontinalis is 5.4699, P. acuta and P. gyrina is 7.6411, P. fontinalis and P. gyrina is 16.6080 showing that P. acuta resembles with P. fontinalis, and both these specimens donot resemble with P. gyrina. P.acuta is an invasive species and shows bioactivity making it a potent candidate for bioactive substances.

Modest sexual size dimorphism and allometric growth: a study based on growth and gonad development in the wolf spider Pardosa pseudoannulata (Araneae: Lycosidae)

ABSTRACT Sexual size dimorphism (SSD) is a notable phenomenon in terrestrial animals, and it is correlated with unusual morphological traits. To date, the underlying sex-specific growth strategies throughout the ontogenetic stage of spiders are poorly understood. Here, we comprehensively investigated how the growth trajectories and gonad development shaped SSD in the wolf spider Pardosa pseudoannulata (Araneae: Lycosidae). We also hypothesized the potential growth allometry among the carapace, abdomen, and gonads of spiders in both sexes. By measuring the size of the carapace and abdomen, investigating developmental duration and growth rate, describing the gonadal sections, and calculating the area of gonads at all instars from hatching to maturity, we demonstrated that SSD results from sex-specific growth strategies. Our results indicated that the growth and developmental differences between both sexes appeared at early life stages, and there was allometric growth in the carapace, abdomen, and gonads between males and females.

Growth pattern, mortality and reproductive biology of common sole, Solea solea (Linneaus, 1758), in the Sea of Marmara, Turkey

The study deals with the growth pattern, mortality, and reproduction of common sole, Solea solea (Linneaus, 1758), from the Sea of Marmara (Turkey). A total of 580 fish specimens were sampled monthly from October 2017 to September 2018. The total length of all sampled individuals ranged from 11.1 to 29.5 cm, corresponding to ages from 1 to 3 years. The length–weight relationship was expressed as W = 0.022 TL2.6838, where the slope indicated negative allometric growth. Growth parameters were L ∞ = 33.7 cm, k = 0.48, and t 0 = −0.18 for all samples. A seasonally oscillating growth model, indicating the amplitude of oscillations, revealed an important seasonal growth pattern. Total, natural, and fishing mortality rates were calculated as 1.42, 0.47, and 1.01, respectively. The exploitation ratio (E = 0.68) indicates that the fishing pressure on the common sole in the Sea of Marmara was high. The sex ratio (♀/♂) was 1.18. The gonadosomatic index (GSI) for females showed that two main spawning seasons were observed: one in spring (May) and one in autumn (September–October). Sizes at the onset of sexual maturity were estimated for both females and males at 21.6 and 18.6 cm, respectively.

Allometric Growth of Sargassum fusiforme (Ochrophyta, Fucales) Organs in the Maturation Period Based on Biomass Analysis of Samples from Gouqi Island

Sargassum fusiforme is a seaweed species that plays an important role in the diverse communities of the flora and fauna of coastal food webs. Assessments of its biomass and energy allocation in addition to allometric organ growth have important ecological value for understanding the community structure, carbon storage, and resource assessment of seaweed beds during periods in which they thrive. In this study, the morphology of Sargassum fusiforme and the biomass of organs and total organisms in the maturation period were studied, and the allometric relationships for different organs of Sargassum fusiforme were analyzed using the standardized major axis (SMA). In the maturation period of Sargassum fusiforme, branch number, height × stem diameter were the prior independent variables, and the optimum biomass was y = 0.002x1.107 (R2 = 0.923). The biomass allocation ratio of blades was the highest (38.33%), followed by stems (32.90%) and receptacles (28.77%). The growth rates of the various organs were found to differ, and the rate of biomass increase for the blades and stems tended to converge. The rate of receptacle biomass growth of Sargassum fusiforme was the highest in the maturation period, and the rate of organ biomass increase was Wb < Ws < Wt < Wr, which reflects the trade-off with energy allocation as a strategy used by Sargassum fusiforme.

Neural control of growth and size in the axolotl limb regenerate

The mechanisms that regulate growth and size of the regenerating limb in tetrapods such as the Mexican axolotl are unknown. Upon the completion of the developmental stages of regeneration, when the regenerative organ known as the blastema completes patterning and differentiation, the limb regenerate is proportionally small in size. It then undergoes a phase of regeneration that we have called the 'tiny-limb' stage, that is defined by rapid growth until the regenerate reaches the proportionally appropriate size. In the current study we have characterized this growth and have found that signaling from the limb nerves is required for its maintenance. Using the regenerative assay known as the Accessory Limb Model, we have found that growth and size of the limb positively correlates with nerve abundance. We have additionally developed a new regenerative assay called the Neural Modified-ALM (NM-ALM), which decouples the source of the nerves from the regenerating host environment. Using the NM-ALM we discovered that non-neural extrinsic factors from differently sized host animals do not play a prominent role in determining the size of the regenerating limb. We have also discovered that the regulation of limb size is not autonomously regulated by the limb nerves. Together, these observations show that the limb nerves provide essential cues to regulate ontogenetic allometric growth and the final size of the regenerating limb.

Seasonal Changes of Length-Weight Relationships and Condition Factor of Three Fish Species from the Tanoe-Ehy Swamp Forest (Côte d’Ivoire)

Aims: The Tanoe-Ehy swamp forest (TESF) is a freshwater swampy area characterized by seasonal variation of environmental parameters and fish diversity. So, the aim of this study was to analyze seasonal variations of growth parameters and condition factors of the three abundant species. Methodology: Specimens were collected by using gill nets and fyke nets, measured and weighed. Length-weight relationship (LWR), Fulton’s condition (KF) and relative condition (KR) factors were analyzed from Standard Length (SL) and body weight (BW). Results: The Standard Length of Clarias buettikoferi, Thysochromis ansorgii and Parachana obscura varied between 9.50 and 29.30 cm, 4.60 and 11.50 cm, 10.70 and 29.30 cm, respectively. The growth type of population was allometric negative for C. buettikoferi and P. obscura and isometric for T. ansorgii. In terms of seasonal variation, C. buettikoferi females and P. obscura specimens exhibited isometric growth in dry seasons (DS) against a negative allometric growth in flooded seasons (FS). In contrast, female and combined sex specimens of T. ansorgii showed positive allometric growth in DS and isometric growth type in FS. KR varied between 0.76 and 2.02 and was significantly higher in FS than in DS, indicating a state of well-being during flooded seasons in the 3 species. Conclusion: There was a significant relationship between length with weight and both condition factor for the three species. This study provided the first data about fish body measurements in the TESF and concluded that LWRs and condition factors of the three fish species were strongly influenced by seasonal variations in hydrological conditions.

Weight-length relationship and condition factor of Mugil cephalus (Linnaeus 1758, Mugilidea) in the special wildlife reserve of Gueumbeul (RSFG) in Senegal

The weight-length relationship and the condition factors are fundamental parameters with several uses in biology, fish ecology and fisheries management. Thus, in the Special Wildlife Reserve of Gueumbeul (SWRG) in Senegal, the weight-length relationship and condition factor were established for Mugil cephalus (Linnaeus 1758). A total of 311 individuals (97 females and 214 males) of M. cephalus were collected by the artisanal fishery using cast nets. The total length and weight ranged from 11.1 to 25 cm and 15.9 to 145.26 g, respectively. The results showed that in the SWRG, both in females (b = 2.60) and males (b = 2.899), M. cephalus had negative allometric growth. The analysis of variance showed no significant difference (p > 0.05) in the coefficients of determination between females (R = 0.96) and males (R = 0.84). Condition factors (K) were 3.07 and 1.23 for males and females respectively for M. cephalus in the reserve.

​Discrimination of Five Gobid Species (Family: Gobiidae) based on Otolith Morphometry

Background: The fishes of family Gobiidae are one of the least studied fishes, especially for otolith structure. The otoliths were possess species specific features. Hence, traits of sagittal otolith of gobid species studied. Methods: Five gobid species Odontamblyopus roseus (Valenciennes, 1837), Trypauchen vagina (Bloch and Schneider, 1801), Glossogobius giuris (Hamilton, 1822), Parachaeturichthys polynema (Bleeker, 1853) and Boleophthalmus dussumieri (Valenciennes, 1837) were investigated by three methods including morphological, shape indices and step wise discriminant function analysis (SDFA). Result: Interrelationship between shape indices investigated, at 95% level of confidence (P less than 0.05), revealed that perimeter of P. polynema and area of T. vagina have isometric growth with their length (b = 3.0071, 2.90, respectively) and otolith area of B. dussumieri have positive allometric growth (b = 4.23077). SDFA, based on otolith morphometry, discriminated species up with 97.18% accuracy. Hence, the results of present investigation can be used for discrimination of the species and as a tool in predicting fish size from the otoliths and in calculating the biomass of these less studied fish species.

How Our Cells Become Our Selves: The Cellular Phylodynamic Biology of Growth and Development

Our lives begin with 1 cell, then 2, then 4, then the trillion cell adult, comprised of cell lineages, tissues, organs. How does this occur? Examination in numbers of cells, N, Cellular Phylodynamics, revealed two previously unappreciated processes: UNI-GROWTH, the slowing of growth that occurs as we become larger, caused by fewer cells dividing, captured by the Universal Mitotic Fraction and Universal Growth Equations, with accuracy confirmed for 13 species, including nematodes, mollusks, and vertebrates; and ALLO-GROWTH, the creation of body parts from Founder Cells, captured by the Cellular Allometric Growth Equation, which describes mitotic expansion by Cell-Heritable change in the Cell Cycle Time. These equations can generate cell lineage approximations, bringing the power of coalescent theory to developmental biology.