Abstract
The monotypic genus Landonia Eigenmann & Henn, 1914 was only known from its type locality in western Ecuadorian drainages. Recent collections revealed the presence of Landonia latidens Eigenmann & Henn, 1914 in Chira and Piura river basins in Peru. Thus, the distribution of this species is extended, constituting the southernmost record of the species.
Link: https://checklist.pensoft.net/article/33221/
This study presents the length-weight relationships (LWRs) for 16 lutjanid species from Visakhapatnam coastal waters, India (16.98°N-20°.2 N, Long. 82.19°-86.53°E). The samples were collected fortnightly between December 2013 and December 2018 from commercially operated fishing gears viz.: the reef fish trap with single and double horse necked funnel (mesh aperture size 4.5 cm) trap measured about 3 ft in length, 4 ft in width and 2.5 ft in height, having a volume of 30 cu ft. The soak time was between 18 to 22 h. Gill nets made of monofilament nylon netting with a mesh size of 80 mm were used in the collection of snapper fishes. The nets were operated 3 h before morning (sunrise) and hauled 1 h after the sunrise. The depth of the net operated varied from 3 to 8 m, whereas the head rope of the net is around 20–25 m in length. The hook number 8 to 11 is used for the fishing of snapper fishery resources in water depth more than 75 m in Visakhapatnam region. The soak time varied from 5 to 10 h. The bottom trawlers (43 mm with a cod end mesh size of 15–25 mm) a depth range of 10 to 55 m, whereas during each fishing period, 3 to 4 hauls are made with a towing period ranging from 1 to 2 h; trawlers (a depth regime of 12 to 55 m, with a mesh size of 400 mm to 25 mm at the cod end). Around 3 to 6 hauls are made during each fishing trip with a towing period of 1to 2 h. All LWRs were significant with r2 values ranged from 0.9504 for Lutjanus lemniscatus to 0.9951 for Lutjanus fulvus and ‘b’ values ranging from Pinjalo pinjalo for 2.5982 Lutjanus quinquelineatus for 3.4993. In addition, new maximum total length for each of the three species L. indicus, L. xanthopinnis and P. pinjalo was also found. The parameters are found great importance to evaluate the relative condition of populations, biology, ecology, species management and their fisheries and stock assessment.
Link: https://link.springer.com/article/10.1007/s41208-019-00174-y
Table 1 Descriptive statistics and length-weight relationship of sixteen snapper fish species from the Visakhapatnam coast, India
Members of the order Cyprinodontiformes are cosmopolitan in tropical and temperate latitudes, widely distributed in freshwater and saline habitats (Rosen & Bailey, 1963). In this order, the family Poeciliidae comprises 42 genera with about 353 species (Nelson, Grande, & Wilson, 2016), which are small and laterally compressed fishes, with body form ranging from extremely elongated (e.g., Tomeurus) to deep‐bodied (e.g., Phallichthys, Carlhubbsia) (Lucinda,
2003). Some species have been introduced in many countries by ornamental aquarists (Magalhães & Jacobi, 2017), and as an alternative measure to biological control of mosquitoes (Azevedo‐Santos, Vitule, Pelicice, & García‐berthou, 2016). Seven species were already registered in Brazilian headwater streams (Magalhães & Jacobi, 2017). The main introduction vector of Poecilids in Brazil is the aquarium hobby, a practice that has gained popularity because of the ease in obtaining a diversity of attractive species. However, certain difficulties in the care of ornamental fish, such as the excessive growth and aggressiveness of some species, motivate the aquarists to release their unwanted fishes into artificial or natural aquatic environments (Magalhães & Jacobi, 2013). This illegal release has introduced not only Poecilia reticulata Peters, 1859 into Brazilian streams, but also some species of Xiphophorus (Magalhães & Jacobi, 2017).
The drainage area of the Iguazu River Basin cross different geological and geomorphological units (Parolin, Ribeiro, & Leandrini, 2010). It has many waterfalls, most notably the Iguazu Falls (82 m high), formed in a geological event dating from the Cretaceous period (Parolin et al., 2010), and which likely generated a cladogenic event for many fish species in the Iguazu River. These waterfalls, located near the mouth of this river, are classified as level‐three barriers for the movement of fish, promoting the isolation of the fish fauna. Additionally, there are more six artificial barriers along the Iguazu River (Baixo Iguaçu, 2019; Baumgartner et al., 2012). The presence of these barriers ensures that the species do not colonize other regions, unless they are aided by human intervention (Rahel, 2007). Such geographical isolation guaranteed to the Iguazu River Basin a small‐sized fish fauna, highly endemic (Baumgartner et al., 2012), and therefore a global biodiversity ecoregion (Abell et al., 2008; Hales & Petry, 2015). This basin is particularly vulnerable to non‐native fish introductions, however, a recent study showed that 27 fish species have already been introduced in the Iguazu River Basin (Gubiani et al., 2018). Such introductions cause negative impacts on endemic fish fauna, increasing the risk of extinctions (Daga, Debona, Abilhoa, Gubiani, & Vitule, 2016; Gubiani et al., 2018).
Link: https://onlinelibrary.wiley.com/doi/full/10.1111/jai.13965
FIGURE 1 Geographic location of sampling sites (black circles) in the lower Iguazu River Basin, highlighting the Bom Retiro stream (black star)
FIGURE 2 Xiphophorus hellerii sampled in Bom Retiro stream, lower Iguazu River Basin, Brazil. (a) adult individual (68.8 mm) (TL); (b) juvenile individual (40 mm) (TL). (TL‐total length)
We analysed the length‐weight relations (LWRs) of 10 fish species inhabiting different habitats from Visakhapatnam, Coast of India. Samples were obtained between August 2013 and December 2016 from commercial trawlers at the local fish landing centre (16.98°N–20.20°N, Long.82.19°–86.53°E). Fishes were captured between 100 and 300 m depth with demersal trawl net (head rope length: 46 m and cod end mesh size: 40 mm with a 38 m high speed. Total length (TL; nearest to 0.1 cm) and body weights (nearest to 0.1 g) were taken from each individual. This study provides new maximum length data for two species (Archamia bleekeri (Günther, 1859) and Ostorhinchus fleurieu (Lacepède, 1802), and LWR estimates for rare deep reef associated fishes are provided for the first time. All LWRs were significant with r2 values ranging from .908 for Sargocentron praslin (Lacepède, 1802) to .981 for Parapercis pulchella (Temminck & Schlegel, 1843) and “b” values ranged from 2.5216 for Parapercis pulchella (Temminck & Schlegel, 1843) to 3.4746 for Ostorhinchus fleurieu Lacepède, 1802.
link: https://onlinelibrary.wiley.com/doi/full/10.1111/jai.13959
TABLE 1 Length weight relationship parameters of 10 fish species of Visakhapatnam coast, India, from August 2013 and December 2016
The relationships among the morphology, trophic ecology, and use of food resources by fish fauna in a pristine stream in Iguaçu National Park (INP), Brazil were evaluated. We expected that the trophic patterns would be explained by ecomorphological variations among fishes and the availability of food resources. Sampling was conducted quarterly from May 2015 to April 2016 using electrofishing. The stomach contents of 599 individuals belonging to nine species were analyzed using the volumetric method. Thirty-two morphological measures related to trophic ecology and body morphology were then converted into 10 ecomorphological indices. The fish assemblage consumed aquatic (Diptera, Ephemeroptera) and terrestrial (Hymenoptera) insects, other aquatic invertebrates, plants, and detritus/sediment. Therefore, the consumption frequencies of these food items were considered representative of their environmental availability. Furthermore, the fish fauna presented wide trophic niche breadths and little diet overlap. Principal component analysis (PCA) was used to classify the fishes’ ecomorphological variations into three ecomorphotypes. The benthonic ecomorphotype comprised species with more depressed bodies that eat detritus/algae and dipteran larvae (Ancistrus mullerae and Corydoras carlae). The nektobenthic ecomorphotype included species with elongated bodies and wider heads and mouths that eat aquatic insects and Aeglidae (Trichomycterus stawiarski and Rhamdia spp.). The nektonic ecomorphotype contained species with more compressed bodies and terminal mouths, which are generalist consumers of allochthonous and autochthonous resources. Morphology was significantly correlated with diet, which suggests that ecomorphological variations together with the availability of food in the environment are the main mechanisms underlying trophic segregation and coexistence among species.
link: https://link.springer.com/article/10.1007/s10641-019-00871-w
Fig. 6 Ordenation of the fish fauna of Manoel Gomes stream, Iguaçu National Park, Iguassu ecoregion, Brazil, produced by the first two axes of the principal components analysis (PCA 1 and PCA 2) applied to the correlation of 10 ecomorphological indices and the mouth orientation. Symbols: (filled blue circle): Astyanx bifasciatus; (filled green square): Astyanax gymnodontus; (red triangle): Astyanax minor; ■ (filled black square): Ancistrus mullerae; ○ (black circle): Bryconamericus ikaa; ◊ (black diamond): Corydoras carlae; (filled dark red triangle): Rhamdia branneri; + (black plus symbol): Rhamdia voulezi; (filled gray circle): Trichomycterus stawiarski
Snappers are commercially important fishes in Indian waters, currently belonging to the order Lutjaniformes, family Lutjanidae. Generally, recognizing species of Lutjanus is a challenging task not only because of overlapping morphological characters, such as shapes, size groups, or colour patterns, but also based on the definition of the species concept or the definition of the threshold for speciation. In India there has not been any updated and accurate study of the genus so far. Besides, identification of the group based on ecological aspects and DNA barcoding tools were confined to limited laboratories. In the present study, ten species of snappers were identified from samples obtained from the major fish landing centres in the Visakhapatnam, Central Eastern coast of India. Snapper species were identified using COI (Cytochrome oxidase I) sequences for DNA barcoding. The validity of the conjecture species-level taxonomy based on COI is assisted with high equivalence search (98–100%) both in BOLD and BLAST, well-distributed genetic distance values.
link: https://www.tandfonline.com/doi/full/10.1080/24701394.2018.1551387?scroll=top&needAccess=true
Figure 1. Map of the Visakhapatnam, Central Eastern Coast of India collection sites of the snapper samples.
Figure 2. Lutjanus argentimaculatus
Figure . L.johnii.
Pseudobunocephalus timbira, new species, is described from streams of the lower Tocantins and the Mearim river drainages, in North and Northeast of Brazil. Pseudobunocephalus timbira can be distinguished from all congeners by having the second hypobranchial and the third basibranchial cartilaginous (vs. ossified). Additionally, it can be dintinguished from P. lundbergi by the following putative apomorphic features within Pseudobunocephalus: posterolateral process of premaxilla present (vs. absent); bony knobs in dorsal lamina of Weberian apparatus absent (vs. present); distal end of posterior margin of 5th parapophysis not enlarged (vs. enlarged); number of ribs three (vs. four or five) and infraorbital sensory canal entering neurocranium via frontal (vs. via sphenotic). It is distinguished from P. bifidus and P. iheringii by having a gracile body not surpassing 34 mm SL (vs. robust body, reaching up to 59 mm SL, respectively); by having the posterior margin of cranial fontanel concave (vs. posterior margin somewhat straight with parieto-supraoccipital extending anteriorly); by having a conspicuous knobby ornamentation on dorsal surface of skull (vs. skull knobs slightly pronounced); by having Weberian ventral blade of hemal canal opened (vs. closed) and by the absence of serrations on the proximal portion of the anterior margin of pectoral-fin spine (vs. serrations covering entire anterior margin of the pectoral spine). Additionally, it can be distinguished from P. amazonicus, P. rugosus and P. quadriradiatus, by having the posterolateral mental barbel with at least one fleshy lobe located proximally along the posterior margin (vs. posterolateral mental barbel simple, not having fleshy lobes). It also differs from P. amazonicus and P. rugosus by having five branchiostegal rays (vs. four). It also can be distinguished from P. amazonicus by having the contact of hyomandibula cartilage with neurocranium limited to the sphenotic (vs. extending to both sphenotic and pterotic); by having the ventral blade of Weberian apparatus open (vs. closed) and by anterior exit of hemal canal in abdominal vertebra (vs. in complex vertebra); from P. rugosus by coloration of proximal portion of caudal fin similar to rest of caudal fin (vs. clear patch) and from P. quadriradiatus by the total number of pectoral fin-rays six (vs. five). Variable characteristics within Pseudobunocephalus species are summarized and comments on the phylogenetic relationships and the disjunct distribution of the new species are made.
link: https://biotaxa.org/Zootaxa/article/view/zootaxa.4586.1.5
FIGURE 1. Dorsal, lateral and ventral views of Pseudobonocephalus timbira, holotype, MPEG 21057, 31.8 mm SL, Brazil, Maranhão, Alto Alegre do Pindaré, Jundiá Creek, Mearim River basin.
FIGURE 2. HRXCT model of skull and anterior body of Pseudobunocephalus timbira, MCN 19274, paratype, 29.2 mm SL. (A) dorsal view, (B) lateral view, and (C) ventral view. ach = anterior ceratohyal; bp = basipterygium; br = branchiostegal rays; cl = cleithrum; cv = complex vertebrae; den = dentary; dp = proximal portion of pectoral-fin spine; fr = frontal; hc = hemal canal; hm = hyomandibula; io = infraorbital; me = mesethmoid; mnp = middle nuchal plate; mx = maxilla; tf = temporal fontanel; pcl = posterior process of cleithrum; pnp = posterior nuchal plate; pfr = pectoral-fin rays; pfs = pectoral-fin spine; pll = posterior lateral line tubules; pmx = premaxilla; po = preopercle; pp = proximal portion of pectoral-fin spine; psc = posterior process of scapulocoracoid; pso = parietosupraoccipital; pto = pterotic; pv5 = parapophysis of fifth vertebra; puh = urohyal; r = ribs; sc = scapulocoracoid; scl = supracleithrum; spo = sphenotic; v6 = sixth vertebra; vh = ventral hypohyal. Limits between selected bones are highlighted in black.
Hemiodus bimaculatus sp. nov., is described from tributaries of the Rio Juruena and Rio Teles Pires in the upper Rio Tapajós basin. The new species is diagnosed from most congeners, except Hemiodus jatuarana, by having a conspicuous circular or horizontally elongate dark blotch on the caudal peduncle (v. inconspicuous in H. iratapuru and absent in the other species). The new species differs from H. jatuarana by having a round midlateral spot on the flank (v. absent in H. jatuarana), 98–121 perforated scales in the lateral line (v. 66–72 in H. jatuarana), 23–28 scale series above and 14–19 below lateral line (v. 12–13 above and 6–7 below in H. jatuarana). Hemiodus bimaculatus is hypothesised to be related to species of the H. microlepis group, from which it also differs by having 11–25 epibranchial (v. 26–34 in H. argenteus, 29–39 in H. microlepis, 21–42 in H. orthonops and 27–35 in H. parnaguae) and 18–31 ceratobranchial (v. 38–50 in H. argenteus, 43–58 in H. microlepis, 32–52 in H. orthonops and 34–48 in H. parnaguae) gill rakers in the first arch.
Link: https://onlinelibrary.wiley.com/doi/abs/10.1111/jfb.13972
FIGURE 1 Hemiodus bimaculatus sp. nov., holotype, MCP uncatalogued, 117.29 mm standard
length, Rio Claro or Rio Água Verde a tributary to Rio Juruena, Amazon basin.
Priscilla C.Silva, Maria Claudia Malabarba, Richard Vari (In memoriam), Luiz R.Malabarba
The DNA extracted from museum alcohol-fixed specimens can be a valuable source of information for solving taxonomic, phylogenetic, ecological and conservational questions. However, this type of DNA, also called ancient DNA, is routinely obtained in small portions and highly fragmented. We have tested two different extraction kits in museum type-specimens of the fish family Characidae. Aiming to increase the DNA yield, we made modifications on a Qiagen manufacturer protocol, in the elution step. Also, to overcome the issue of DNA fragmentation, we applied our efforts in Sanger sequencing, to find a highly variable and, in result, informative COI fragment. Based on our results, there is no correlation between amount of the DNA extracted and the age of the sample. The Sanger sequencing generated sequences which are useful in solving taxonomic puzzles. Here are presented the customization and guidelines that allowed us to recover DNA from the archived fish specimens.
link: https://www.sciencedirect.com/science/article/pii/S221501611930158X
Fig. 1. Right side of the lectotype of Deuterodon pedri (MCZ 21081) before the incision (A) and after the incision (B), exemplifying position and size of the incision.
Uma nova espécie de Pyrrhulina é descrita baseada em 60 espécimes dos afluentes do rio Amazonas: rio Anapu, rio Capim, rio Guamá e rio Xingu, e drenagens costeiras no estado do Pará, Brasil. A nova espécie distingue-se de todas as congêneres por ter a faixa primária (faixa horizontal de pigmentação escura que se estende posteriormente do focinho) terminando na borda distal do opérculo. Em todas as outras espécies de Pyrrhulina, a faixa primária é restrita ao focinho ou continua além da cabeça (para incluir pelo menos as quatro escamas anteriores da série da linha lateral).
Palavras-chave: Padrão de colorido; Peixes de água doce; Pyrrhulininae; Taxonomia; Teleostei
Fig. Lateral view of Pyrrhulina capim, new species, rio São José, Bragança, Pará, Brazil. a. holotype, UFRGS 27300, 54.4 mm SL, male; b. paratype, UFRGS 25562, 40.4 mm SL, female.
Fig. Map of northern portion of South America, with the distribution of Pyrrhulina capim, new species. The polygons represent the localities of the holotype and paratypes.