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Giuris laglaizei -- a commercially valuable freshwater eleotrid fish found in Lake Mainit, the Philippines -- has seen its population decline due to overharvesting and various anthropogenic activities affecting its habitat. The study evaluated the relationship between length/widthweight, the condition factor (CF) of G. laglaizei, and the morphometric variations among its colormorphs. The study reports the occurrence of new colormorph (light pink) in the lake. A total of 255 individuals were measured and revealed that most samples are categorized as small (71-96 mm) to medium (97--120 mm) marketable sizes. Exploratory analysis of TL-BW, SLBW, MAXH-BW, and MINH-BW best fits the power equation. The length-weight (TL-BW and SL-BW) relationships depicted a positive allometric growth pattern (b = 3.88 and b = 3.65; p < 0.01). Computed Fulton's CFs were higher (> 1) among colormorphs and combined samples. In addition, multivariate analysis of morphometric traits of the colormorphs indicated high variability (p < 0.001). Data ordination implied variability in the morphological traits of G. laglaizei among colormorphs (light pink, light yellow, and dark yellow) supported by principal coordinate analysis and analysis of variance. The morphological variations were more prominent in the head, ventral, and dorsal parts of G. laglaizei (F-value; p < 0.001). The morphological variability detected can be attributed to their niches, wherein colormorphs have been reported to have different environmental preferences and feeding habits. Overall, the study provided a computational analysis of its marketable size structure, CF, and morphological variations, which is crucial for sustainable utilization and conservation management of the species. [ABSTRACT FROM AUTHOR]

Rapid urbanization boosts the material demand of cities and leads to serious environmental problems, such as water shortage and air pollution. To achieve better governance of cities, stakeholders need to deeply understand urban material utilization. Taking 327 cities in China as examples, this study analyzes the urban material characteristics from a metabolic perspective. We investigated the spatiotemporal changes in the material base of these cities from 2000 to 2020, including material flow and material stock. We further explored the allometric growth patterns of urban material flow and material stock at different scales (e.g., individual, group, and community). Results show that cities have metabolic processes as natural organisms; they differentiate into many types and exhibit allometric growth patterns. There is a consistency of material metabolic patterns in most cities. The growth of material flows (+43%) and material stocks (+135%) was evident in all cities during 2000–2020. However, the material metabolism of Chinese cities exhibits diverse allometric growth patterns across the individual, group, and community scales. This study can provide simple but effective quantitative indicators for the investigation of urban material utilization, and can support distinct policy implications for sustainable urban material‐based planning and management. [ABSTRACT FROM AUTHOR]

In the present study, morphometric and meristic characteristics of the cornetfishes, Fistularia spp., from the Egyptian Mediterranean coast were described. The linear length-length relationships and the allometric growth pattern were also investigated. Specimens were sampled from October 2017 to March 2019, by trawling in the marine area along the west of Alexandria City. The data analysis showed that the red cornetfish, Fistularia petimba (Lacepède, 1803), which is one of the IUCN Red List, was observed in this zone for the first time. Fistularia petimba dorsal, anal, pectoral, ventral, and caudal fins formulas were defined as follows: D 15; A 15; P (I + 14); V (i + 5); and C 18. This fish species was characterized by, elongated bony plates that were present anteriorly and posteriorly to the dorsal fin with a number of 23 bony plates anterior to the dorsal fin with the absence of gill rakers. Arched lateral line and sharp spines were on the posterior ossifications. The body color was orange–brown on the upper side and white on the bottom with transparent fins and a touch of orange color on the tips. The bluespotted cornetfish, Fistularia commersonii (Rüppell, 1838) reached 107.5 cm in total length. Its fins formulas were as follows: D (13–17); A (12 – 18); P (I + 13) – (I + 15); V (i + 5); and C 18. The vertebrae count was between 84 and 88, including the urostyle that had the first 4 vertebrae fused and without bony plate or gill rakers. Arched lateral line and rows of blue spots or line appeared on the back. The body color varied from brownish to olive on the upper side and white on the bottom with transparent fins and a touch of rosy pink color on the tips. The linear regression equations for the different morphometric characters of F. commersonii were highly correlated (R2 > 0.90). The allometric coefficients (b) of the various morphometric characters of F. commersonii were also studied. Further studies on the biological and fisheries parameters are recommended for F. commersonii as well as following the presence and establishment of F. petimba in the Egyptian waters.

In the present study, morphometric and meristic characteristics of the cornetfishes, Fistularia spp., from the Egyptian Mediterranean coast were described. The linear length-length relationships and the allometric growth pattern were also investigated. Specimens were sampled from October 2017 to March 2019, by trawling in the marine area along the west of Alexandria City. The data analysis showed that the red cornetfish, Fistularia petimba (Lacepède, 1803), which is one of the IUCN Red List, was observed in this zone for the first time. Fistularia petimba dorsal, anal, pectoral, ventral, and caudal fins formulas were defined as follows: D 15; A 15; P (I + 14); V (i + 5); and C 18. This fish species was characterized by, elongated bony plates that were present anteriorly and posteriorly to the dorsal fin with a number of 23 bony plates anterior to the dorsal fin with the absence of gill rakers. Arched lateral line and sharp spines were on the posterior ossifications. The body color was orange–brown on the upper side and white on the bottom with transparent fins and a touch of orange color on the tips. The bluespotted cornetfish, Fistularia commersonii (Rüppell, 1838) reached 107.5 cm in total length. Its fins formulas were as follows: D (13–17); A (12 – 18); P (I + 13) – (I + 15); V (i + 5); and C 18. The vertebrae count was between 84 and 88, including the urostyle that had the first 4 vertebrae fused and without bony plate or gill rakers. Arched lateral line and rows of blue spots or line appeared on the back. The body color varied from brownish to olive on the upper side and white on the bottom with transparent fins and a touch of rosy pink color on the tips. The linear regression equations for the different morphometric characters of F. commersonii were highly correlated (R2 > 0.90). The allometric coefficients (b) of the various morphometric characters of F. commersonii were also studied. Further studies on the biological and fisheries parameters are recommended for F. commersonii as well as following the presence and establishment of F. petimba in the Egyptian waters. [ABSTRACT FROM AUTHOR]

The first record of the amphioxus Branchiostoma californiense on seagrass patches of Halodule wrightii in the Gulf of California is reported. Sixty individuals (19 males, 18 females, and 23 undifferentiated) were collected in May 2017 at Bahía Balandra, Gulf of California, from subtidal seagrass patches at a depth of 0.5 m at low tide. The length and weight ranged from 15.88-28.44 mm and from 0.01-0.11 g for females and 11.7-27.9 mm and 0.01-0.09 g for males, respectively. The minimum size of sexually mature individuals was 11.70 mm for males and 15.88 mm for females; 62% of the specimens were sexually mature. Analysis of the total length-weight relationship suggested an allometric growth pattern among females, males and undifferentiated individuals, whereas an analysis of the entire sample suggested an isometric growth pattern. Typical and additional morphological characters were used to identify the amphioxi. High morphological variability between individuals was found, suggesting the presence of several morphotypes. Branchiostoma californiense had been previously reported as exclusively associated with bare sandy areas, but our study shows that this species can also be found in seagrass patches, using them as breeding and feeding grounds. Thus, seagrass patches are evidenced as suitable habitats for amphioxus. [ABSTRACT FROM AUTHOR]

Overfishing and depletion of wild fish stock are a major problem facing the fisheries sector in Nigeria, hence the need to carry out an extensive research on the biology of wild species. The aim of this study was to provide contributory information on the biology of Synodontis schall from Ogun River, Nigeria. Ninety fish samples were obtained from local fishermen bi-monthly between February and August, 2015. The length and weight of the specimen were measured and length-weight relationship was determined using the formula W=aLb. Gut content of the specimens was studied using the frequency of occurrence and numerical method. Index of stomach fullness was also determined monthly. Gut content revealed both plants and animal items consisting mainly of insects, rotifers, crustaceans, fish parts, algae etc. indicating omnivorous feeding habit. Percentage stomach fullness was higher during the peak of the wet season (July and August). Total length, standard length and weight of specimens were ranged between 15.4 and 29.0 cm, 10.1 and 23.5 cm and 50 g and 198 g, respectively. Length-weight analyses gave the values of 'b', 'a', and 'r' as 1.520, 1.115 and 0.8967, respectively, exhibiting a negative allometric growth pattern. The study therefore, shed light on the biology of the species and thus, contributes to documented facts about the species from the Akomoje reservoir, with a view towards developing the aquaculture of the reservoir. [ABSTRACT FROM AUTHOR]

The present study provides information on weight-length relationship (WLR) and Fulton's condition factor (K) of the alligator pipefish, Syngnathoides biaculeatus (Bloch, 1785) sampled from Palk Bay (PB) and Gulf of Mannar (GoM) regions, southeast coast of India. The pooled estimate for the parameter b of the WLR for S. biaculeatus (n = 217) was determined to be 1.75, indicating the negative allometric growth pattern (b < 3). The K values ranged from 0.65 to 1.35 (pooled, 0.84) and from 0.68 to 1.27 (pooled, 0.85) for populations of S. biaculeatus collected from PB (n = 120) and GoM (n = 97) respectively. The results may help address the concerns of conservation of S. biaculeatus in the wake of habitat loss and/or incidental by-catch. [ABSTRACT FROM AUTHOR]

The early morphological development and allometric growth pattern of Caspian kutum (Rutilus frisii kutum) during early development (from 0-35 days post hatch=dph) was studied. Morphological data were obtained using ImageJ software from 2D pictures and allometric growth patterns were computed based on Log10 y = Log10 α + βLog x function. Based on inflexion point of morphological traits and body shape changes, the early developmental of kutum were divided into Eleuthero-embryo, Propterygio-larval, Pterygio-larval" and younger juvenile phases, each of which included vital developmental events. Rapid and intense changes occurred during Eleuthero-embryo and Propterygio-larvae stages such as development of gills, depletion of yolk-sac and exogenous feeding, development of feeding apparatus, sense organs and organs related to swimming performance. The results also revealed that developmental changes occurred in agreement with the inflexion points of morphological characters and their developmental priority imply on functional importance of feeding, respiration and swimming related structures. [ABSTRACT FROM AUTHOR]