Comparative floral morphometrics in day-flowering, night-flowering and self-pollinated Caryophylloideae (Agrostemma, Dianthus, Saponaria, Silene, and Vaccaria)

Morphological variation of flowers with different pollination modes was studied in 53 species representing five genera (Agrostemma, Dianthus, Saponaria, Silene s.l., Vaccaria) of the subfamily Caryophylloideae. All species were classified a priori as either diurnal, nocturnal, or selfing. Canonical discriminant analysis (CDA) of 13 floral characters revealed significant correlations between floral morphometry and pollination modes. A CDA of taxonomical groups represented with more than three species (Dianthus, and subgroups of Silene s.l.: Lychnis, Silene s.str., and Viscaria), revealed that the discrimination between these four taxa, based on the same floral characters, is also well supported. Main factors for the discrimination of the species with different pollination modes were characters that (a) define nectar accessibility (calyx length, calyx tooth length), (b) are related to the positioning of anthers and stigmatic areas in relation to pollinators and (c) are important for the visual attractiveness of flowers (plate width). The functional distance between the nectar source (anthophore base) and contact zone with pollinators (style tips), given as the sum of anthophore length, ovary length, and style length (hence called AOS-complex) is better correlated with the calyx length than the single characters. Further, the total AOS-complex length differs significantly between pollination modes suggesting that these characters form a functionally linked complex that is related to the pollen placement on, and stigma contact with, the pollinator's body. However, the contribution of anthophore and style length to the total AOS-complex differed significantly between Silene s.l. and other taxa indicating that the taxonomic groups follow different evolutionary ways for the construction of the functionally linked AOS-complex.     

Biometric relationships between body and otolith measurements in nine demersal fishes from north‐eastern Tasmanian waters,Australia

Relationships between fish and otolith measurements were analyzed in nine demersal fishes from the north‐eastern Tasmanian waters: Foetorepus calauropomus, Trachurus declivis, Parequula melbournensis, Neosebastes scorpaenoides, Platycephalus aurimaculatus, Platycephalus bassensis, Platycephalus conatus, Lepidotrigla mulhalli and Lepidotrigla vanessa. The values of exponent b from the relationships between fish weight and fish total length, total length and otolith length, total length and otolith width, and fish weight and otolith length were estimated. All above relationships were statistically significant. The analysis of covariance (ANCOVA) was used to test the effect of the categorical factor of species in the fish length and otolith length relationship. Significant differences in fish length and otolith length relationship between species were highlighted in both gurnards and flatheads. Results from this study will provide novel information on quantitative biometric relationships between body and otolith measurements of fish species in Australian waters.     

Length–weight and length–length relationships of eight fish species from Bohai Bay,China

Length–weight and length–length relationships (LWRs and LLRs) for eight fish species collected quarterly by trawl net in Bohai Bay, China, were estimated in a total of 1,395 specimens from 2012 to 2015. These were Pholis fangi, Setipinna taty, Engraulis japonicus, Larimichthys polyactis, Thryssa kammalensis, Scomberomorus niphonius, Johnius grypotus and Sardinella zunasi. The LWRs for the last two fish species are first reports for FishBase.     

Length–weight and length–length relationships for nine fish species from Lhasa River Basin,Tibet, China

The present study reports length–weight relationships (LWR) and length–length relationships (LLR) for five native freshwater fish species (Schizopygopsis younghusbandi, Triplophysa orientalis, T. tibetana, T. stewartii and T. stenura) and four introduced freshwater fish species (Pseudorasbora parva, Carassius auratus, Micropercops cinctus and Oryzias latipes) captured in the Lhasa River Basin, Tibet, China. Five of the LWRs are presented for the first time.     

Distribution and Relative Size of the Swim Bladder in Percina, With Comparisons to Etheostoma, Crystallaria, and Ammocrypta (Teleostei: Percidae)

The distribution of the swim bladder was examined in 20 species representing all four genera (Percina, Etheostoma, Crystallaria, and Ammocrypta) of darters (Etheostomatini). Including data on species examined in other studies, swim bladders have been found in 15 of 17 species of Percina, but were absent in Crystallaria asprella, Ammocrypta pellucida, and the 18 species of Etheostoma examined. Relative swim bladder length in Percina was shown to be positively correlated with body size. Although not statistically significant, swim bladder size also correlates with habitat (riffle, run, or pool) and swimming behavior (midwater or benthic).     

Length–weight relationships of five fish species from the streams of Maoershan National Forest Park,Heilongjiang, China

In this study the length–weight relationships of five fish species belonging to four families and five genera were analyzed from the streams of Maoershan National Forest Park in China. A total of 221 specimens were used to estimate the relationship parameters. These species (Lethenteron reissneri, Cobitis granoei, Misgurnus mohoity, Rhynchocypris percnurus and Perccottus glenii) had no previous estimate in FishBase.     

Length–weight relationships for selected fish species from a coastal lagoon influenced by freshwater seeps: Yucatan peninsula,Mexico

The present work analyzes the relationship between length and weight for 28 fish species belonging to 16 families in Celestun lagoon, a natural marine reserve located in southeast Mexico that is influenced by freshwater seeps. With interrupted periods, a total of 14 846 specimens were collected from 1990 to 2006. The most abundant species were Eucinostomus argenteus, Eucinostomus gula, Anchoa mitchilli and Lagodon rhomboides. Exponents varied around b = 3.17 at P < 0.001, indicating a preference for isometric relationships. This study presents the first estimation of LWR for four species (Menidia colei, Lucania parva, Floridichthys polyommus, Garmanella pulchra) and the maximum length record for F. polyommus (19.5 cm standard length) that is greater than previously recorded.     

Length–weight relationships of seven freshwater fishes from the JiangSu province,China

The length‐weight relationships (LWRs) are presented for seven freshwater fish species (Odontobutis potamophila, Protosalanx chinensis, Acheilognathus chankaensis, Megalobrama skolkovii, Pelteobagrus vachelli, Macropodus chinensis, Pseudobrama simoni) from JiangSu province in China. A total of 1340 specimens were sampled and measured between August 2012 and September 2013. No information regarding the LWRs of these species was available in FishBase.     

Length–weight relationships and length at first maturity for fish species in the upper Miranda River,southern Pantanal wetland,Brazil

Length–weight relationships (LWR) were estimated for 17 species and total length at first maturity (L50) for three species of freshwater fishes from the Miranda River, southern Pantanal, Brazil. The b values were compared for some species in the Paraguay River basin with the northern (Cuiabá River) part of the basin; differences in length–weight relationships were significantly different for Pseudoplatystoma corruscans, P. reticulatum (syn. P. fasciatum). First references on L50 and LWR are presented for two and eight fish species, respectively, as well as the new maximum total length for two species.     

Length‐weight relationships of eight freshwater fishes from the Yangtze River and Lake Taihu,China

The length‐weight relationships (LWRs) are presented for eight freshwater fish species (Acheilognathus macropterus, Saurogobio dabryi, Saurogobio gymnocheilus, Sinobdella sinensis, Pelteobagrus eupogon, Rhinogobius cliffordpopei, Neosalanx jordani, and Silurus meridionalis) from the Yangtze River and Lake Taihu. A total of 1044 specimens were sampled and measured between July 2012 and June 2014. Among the eight species, five species have no LWR estimates in FishBase.     

The weight‐length relationship of fish species found in the tidal creeks of the Amazon estuary,northern Brazil

The present study estimated the a and b parameters of the weight‐length relationship of five fish species that inhabit the tidal creeks of islands in the Amazon estuary: Colomesus asellus, Geophagus proximus, Lithodoras dorsalis, Pseudauchenipterus nodosus, Pachypops fourcroi. The species were collected quarterly between October 2013 to July 2014 using block nets made from 20 mm mesh size. The b coefficient of the regression of the weight on the total length of these species ranged from 2.71 to 3.14. These are the first reference on the weight‐length relationship for three species and the new maximum length recorded for two species.     

Length–weight and length–length relationships of four native fish species from the Yalong River,China

Length‐weight and length‐length relationships were estimated for four native fish species from the Yalong River and its tributaries, China. A total of 976 specimens were collected monthly using trap nets and electric fishing in May 2013 and July 2015 to February 2016. This study presents the first references on LWRs (length–weight relationships) and LLRs (length–length relationships) for three species (Gymnocypris firmispinatus, Paracobitis variegatus and Euchiloglanis kishinouyei). Moreover, maturation length, absolute fecundity and predominant food items for the four species were also described in the study.     

Species diversity of the genus Osmundea (Ceramiales,Rhodophyta) in the Macaronesian region

Species diversity within the genus Osmundea in the Macaronesian region was explored by conducting a comprehensive sampling in the Azores, the Canary, and the Madeira archipelagos. Toward identification, all specimens were first observed alive to verify the absence of corps en cerise, a diagnostic character for the genus and morphometric data were measured (thallus length and width, first‐order branches length and width, branchlets length and width, cortical cell length and width in surface view, cortical cell length and width in transverse section). Specimens were sequenced for COI‐5P (39 specimens) and three species delimitation methods (Generalized Mixed Yule Coalescent, Automatic Barcode Gap Discovery method, and Poisson Tree Processes) were used to assess the threshold between infra‐ and interspecific relationships. Subsequently, one or several sequences of plastid‐encoded large subunit of RuBisCO (21 specimens) per delimited species were generated to assess the phylogenetic relationships among Macaronesian Osmundea. Moreover, for each delineated species, vegetative and reproductive anatomy was thoroughly documented and, when possible, specimens were either assigned to existing taxa or described as novel species. This integrative approach has provided data for (i) the presence of O. oederi, O. pinnatifida, and O. truncata in Macaronesia; (ii) the proposal of two novel species, O. prudhommevanreinei sp. nov. and O. silvae sp. nov.; and (iii) evidence of an additional species referred as “Osmundea sp.1,” which is a sister taxon of O. hybrida.     

Feeding habits of the blue shark, Prionace glauca, and salmon shark, Lamna ditropis, in the transition region of the Western North Pacific

We describe the feeding habits of 70 blue sharks (Prionace glauca) and 39 salmon sharks (Lamna ditropis) caught at 0–7 m depth at night by research drift gillnets in the transition region of the western North Pacific during April–May of 1999 and 2000. Blue sharks of 50–175 cm total length fed on a large variety of prey species, consisting of 24 species of cephalopods and 16 species of fishes. Salmon sharks of 69–157 cm total length fed on a few prey species, consisting of 10 species of cephalopods and one species of fish. Important prey for the blue sharks were large, non-active, gelatinous, meso- to bathypelagic cephalopods (e.g., Chiroteuthis calyx, Haliphron atlanticus, Histioteuthis dofleini and Belonella borealis) and small myctophid fishes. Important prey for the salmon sharks were mid-sized, active, muscular, epi- to mesopelagic squids (e.g. Gonatopsis borealis, Onychoteuthis borealijaponica and Berryteuthis anonychus). Our results suggest that blue sharks feed on cephalopods mainly during the daytime when they descend to deep water. Salmon sharks may feed opportunistically with no apparent diurnal feeding period. Blue sharks and salmon sharks have sympatric distribution in the transition region in spring; they have different feeding habits and strategies that reduce competition for food resources.     

Length–weight relationships of five endemic fish species from the lower Yarlung Zangbo River,Tibet, China

The length–weight relationships were estimated for five endemic fishes (Schizothorax curvilabiatus, Schizothorax molesworthi, Garra kempi, Neolissochilus hexagonolepis, Exostoma labiatum) from the Yarlung Zangbo River in Tibet, China. Fishing gear used for sampling included 4 cm mesh gill nets (100 m long × 1.2 m high) and electrofishing, from December 2015 to January 2016. Three of the species have new records of maximum length in FishBase.     

Length–weight relationships for five fish species caught in Keban Dam Lake,Turkey

Length–weight relationships (LWR) are presented for five commercial freshwater fish species (Luciobarbus esocinus, Heckel, 1843; Capoeta trutta, Heckel, 1843; Barbus lacerta, Heckel, 1843; Luciobarbus mystaceus, Pallas, 1814 and Capoeta umbla, Heckel, 1843) collected from Keban Dam Lake located in eastern Anatolia, Turkey. Studied samples were obtained between July and December 2008 using commercial gill nets. For each species the sample size, length range, weight range, length‐weight relationships, 95% confidence intervals of a and b, coefficient of correlation and growth type are given. Values of b were between 2.915 (Luciobarbus esocinus) and 3.079 (Copoeta trutta) and r² values from 0.919 (Copoeta trutta) to 0.987 (Barbus lacerta) in the study. New maximum length and length–weight relationships are reported for Barbus lacerta and Luciobarbus mystaceus.     

Notes on age determination,size and age structure,longevity and growth of co-occurring macrourid fishes

Nineteen species of the deep-water fish family Macrouridae inhabit the Mid-Atlantic Ridge (MAR) of the North Atlantic. Size and age structure, longevity and length at age were explored for seven of the more abundant species: Coryphaenoides armatus, Coryphaenoides brevibarbis, Coryphaenoides carapinus, Coryphaenoides guentheri, Coryphaenoides mediterraneus, Coryphaenoides rupestris and Macrourus berglax. The otoliths from these species had growth increments resembling those accepted as annuli in other deep-water species for which validation experiments have been conducted. Based on the counts of these growth increments, age estimates were derived as the basis for studies of age structure, growth and longevity. All the species appeared to have relatively low growth rates, but the interspecific variation in longevity illustrates that there is a considerable variation within the family and among species inhabiting the same deep-sea environment. Most of the species likely complete full life cycles on the MAR, but it is probable that both the youngest and the largest-oldest individuals of some of the species were not sampled adequately.     

Predation on invasive redclaw crayfish Cherax quadricarinatus by native fishes in the Kafue River,Zambia

The stomach contents of eight species of predatory or omnivorous fish caught in gillnets in the Kafue River in May and June 2010 were examined to determine the relative importance, expressed as ‘prominence value’ (PV), of crayfish Cherax quadricarinatus in their diet. Four species, Clarias gariepinus, Schilbe intermedius, Serranochromis robustus and Serranochromis angusticeps, had fed on C. quadricarinatus. The PV of C. quadricarinatus was highest in C. gariepinus, in which the quantity and size of crayfish eaten was significantly correlated with standard length (SL) of fish >200 mm SL. Predated C. quadricarinatus were significantly smaller (mean carapace length [CL] 30 mm; SE 1.2) than those caught in gillnets (mean CL 76 mm; SE 0.9). No C. quadricarinatus remains were found in the stomachs of Oreochromis andersonii, Synodontis macrostigma, Serranochromis macrocephalus or Mormyrus lacerda.     

Length‐weight relationships of three cyprinid fishes from Sirwan River,Kurdistan and Kermanshah provinces in western Iran

The length–weight relationships (LWR) for three fish species collected in Sirwan River, located in Kurdistan and Kermanshah provinces, western Iran, were estimated. The values of the slope parameter (b) in the length–weight relationship equations were determined as 3.086 for Alburnus mossulensis, 3.382 for Alburnus filippii and 3.425 for Capoeta damascina, all significantly different from the expected b = 3 value, indicating a positive allometric growth pattern for all the three species.     

Arbuscular mycorrhizal fungi associated with the Meliaceae on Hainan island, China

Species richness, spore density, frequency of occurrence, and relative abundance of AM fungi were determined in rhizosphere soil samples from nine tropical rainforest sites on Hainan island, south China, and the arbuscular mycorrhizal (AM) status of members of the Meliaceae was examined. All 28 plant taxa investigated (25 species including two varieties of 1 species and three varieties of another) were colonized by AM fungi. The mean proportion of root length colonized was 56% (range 10–95%). Vesicles were observed in 27 and hyphal coils in 26 of the 28 plant taxa. Mycorrhizas were of the Paris-type or intermediate-type, with no Arum-type mycorrhizas observed. Species richness of AM fungi varied from 3 to 15 and spore density from 46 to 1,499 per 100 g rhizosphere soil. Of 33 AM fungal taxa in five genera isolated and identified, 18 belonged to Glomus, 9 to Acaulospora, 1 to Entrophospora, 2 to Gigaspora, and 3 to Scutellospora. Acaulospora and Glomus were the dominant genera identified. Glomus claroideum was the taxon most commonly isolated, with a frequency of occurrence of 56.5% and relative abundance of 10.4%. A positive correlation was found between percentage of root length colonization and species richness. However, there was no correlation between spore density and percentage of root length colonized by AM fungi.