scholarly journals A record of anopthalmia in Mystus tengara (Hamilton, 1822) from Assam

2014 ◽  
Vol 6 (2) ◽  
pp. 589-593
Author(s):  
Jyotish Barman ◽  
A. K. Jaiswar ◽  
S. K. Chakraborty ◽  
Shrinivas Jahgeerdar ◽  
W. S. Lakra

An abnormal case of anopthalmia in a striped catfish Mystus tengara (66.8 mm in standard length) from Assam is reported in this communication. Thirty eight morphological characters of the abnormal specimen were also studied and compared with normal specimens to observe variation in the morpho-meristic traits, if any. In the abnormal specimen, the proportionate height of the dorsal fin (31.1 mm) and nasal barbel length (75.9 mm) was found to be higher compared to that of the normal specimens (21.6 – 26.5 mm and 47.9 – 72.5 mm, respectively). While the body depth of anus was higher in case of normal specimens (19.1 – 29.2 mm) compared to abnormal specimen (14.5 mm). However, no marked variation was observed in meristic characters. This anomaly does not seem to have affected morphological aspects. Factors like weed infestation, pesticide and herbicide application adversely affecting the habitat is believed to be the cause of such deformity. The abnormality does not seem to have affected the overall growth of the fish.

Zootaxa ◽  
2019 ◽  
Vol 4679 (1) ◽  
pp. 97-106
Author(s):  
TIE-JUN WU ◽  
JIAN YANG

Sinibotia lani, a new botiid loach is described from the Zuojiang River, located in Guangxi Autonomous Region, China. The species differs from other members of Sinibotia by a combination of the following morphological characters: body depth 17.5–21.1% SL; snout length shorter than postorbital length of head; eye diameter 10.2–13.2% HL; interorbital width 16.0–18.6% HL; suborbital spine reaching or extending beyond postorbital margin of eye; lower lip with pair of fleshy button-like clusters of papillae; dorsal-fin origin opposite to pelvic-fin origin, pelvic fin not reaching anus; includes six dark vertical bars on the body. A key to the species of Sinibotia is provided. 


Zootaxa ◽  
2019 ◽  
Vol 4604 (2) ◽  
pp. 369 ◽  
Author(s):  
RAFAEL BURGER ◽  
FERNANDO R. CARVALHO ◽  
ANGELA M. ZANATA

A new species of Astyanax from the upper rio Paraguaçu basin, Chapada Diamantina, Bahia, Brazil, is described. Astyanax sincora shares characters currently used to define the Astyanax scabripinnis species complex, as highest body depth approximately at vertical through pectoral-fin midlength and a low number of branched anal-fin rays (13–17). It differs from its congeners by a combination of characters, including eight branched dorsal-fin rays, six branched pelvic-fin rays, presence of bony hooks in pectoral and anal fins of males, dark midlateral line or stripe initiating posteriorly to the vertically elongate humeral blotch, and by the presence of 30–35 scales in the median longitudinal series. The generic positioning of the new species and some polymorphic morphological characters in Astyanax are briefly discussed. The degree of completeness of the lateral line in Hyphessobrycon balbus is discussed. [Species Zoobank registration: urn:lsid:zoobank.org:pub:D708FE7E-3FB5-4729-B438-779717F7ED1A] 


2020 ◽  
Vol 723 ◽  
pp. 77-107
Author(s):  
Erick Cristofore Guimarães ◽  
Pâmella Silva De Brito ◽  
Pedro Henrique Negreiros Bragança ◽  
Jadson Pinheiro Santos ◽  
Axel Makay Katz ◽  
...  

Two new species, Hyphessobrycon frickei Guimarães, Brito, Bragança, Katz & Ottoni sp. nov. and H. geryi Guimarães, Brito, Bragança, Katz & Ottoni sp. nov., are herein described, based on seven different and independent species delimitation methods, and on molecular and morphological characters, making the hypothesis of these new species supported from an integrative taxonomy perspective. They belong to the “Rosy tetra” clade, which is mainly characterized by the presence of a dark brown or black blotch on the dorsal fin and the absence of a midlateral stripe on the body. These two new species are distinguished from the other members of this clade mainly by the arrangement, shape and color pattern of humeral and dorsal-fin spots, as well as by other characters related to scale counts and body pigmentation. The placement of the new species within the “Rosy tetra” clade was based on the combination of morphological character states mentioned above and corroborated by a molecular phylogenetic analysis using the mitochondrial gene cytochrome oxidase subunit 1. In addition, a new clade (here termed Hyphessobrycon copelandi clade) within the “Rosy tetra” clade is proposed based on molecular data, comprising H. copelandi, H. frickei sp. nov., H. geryi sp. nov. and a still undescribed species. Our results corroborate the occurrence of hidden species within the “Rosy tetra” clade, as suggested by previous studies.


2014 ◽  
Vol 12 (2) ◽  
pp. 291-300 ◽  
Author(s):  
James Anyelo Vanegas-Ríos ◽  
María de las Mercedes Azpelicueta ◽  
Hernán Ortega

Chrysobrycon yoliae, new species, is described from a drainage flowing into the río Yucamia basin, río Ucayali basin, Peru. Chrysobrycon yoliaeis readily distinguished from its congeners by the anterior tip of pelvic bone situated anterior to the fifth rib (vs. situated posterior to the fifth rib), the presence of 20-26 dentary teeth (vs. 11-19), and the possession of a terminal lateral-line tube between caudal-fin rays 10 and 11 (vs. the absence of this tube, except in C. eliasi). The new species differs from C. eliasiand C. myersiby the presence of teeth on third pharyngobranchial (vs. the absence of teeth on this bone) and also differs from C. eliasiby the dorsal-fin origin situated at vertical through anal-fin rays 5 to 7 (vs. located at vertical through anal-fin rays 8 to 10), the posterior extent of the ventral process of quadrate reaching the vertical through posterior margin of symplectic (vs. not reaching the vertical through posterior margin of symplectic), the dorsal-fin to adipose-fin length 26.8-28.8% SL (vs. 23.9-26.8% SL), and the body depth at dorsal-fin origin 34.4-42.2% SL (vs. 24.1-34.5% SL). A key for the identification of Chrysobryconspecies is provided.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Gabriel de Carvalho Deprá ◽  
Renata Rúbia Ota ◽  
Oscar Barroso Vitorino Júnior ◽  
Katiane Mara Ferreira

ABSTRACT Two new species from the upper rio Tocantins basin are described in Knodus based on the traditional definition of the genus. The new species are distinguished from other congeners by meristic and morphometric characters, such as the number of cusps in the premaxillary and dentary teeth, the number of scale series between dorsal-fin origin and lateral line, the orbital diameter and the body depth. With the two new species, the number of endemic species in the upper rio Tocantins basin upstream of the mouth of the rio Paranã, rises to 53 (89 to the confluence with rio Araguaia). The existence of a meristic character that changes through ontogeny (allomery), viz. the number of scale series between dorsal-fin origin and lateral line, was detected in some species of Knodus through a regression analysis. Additionally, this paper describes an unambiguous, more informative and precise new method for counting vertebrae, which will enhance the efficacy of this trait in species comparisons.


2020 ◽  
Vol 33 (2) ◽  
pp. 163-182
Author(s):  
Mara Braverman ◽  
Daniel Brown ◽  
E. Marcelo Acha

Fish metamorphosis is an important ontogenetic process with a key role on early stages survival and on successful recruitment to adult populations. The whitemouth croaker (Micropogonias furnieri) is an important commercial resource for the coastal fisheries of Argentina and Uruguay. Metamorphosis, using morphometric and morphological analyses during larval development was studied. Changes in morpho-meristic characters before and after metamorphosis were employed to determine the length interval of this transition by employing Principal Component Analysis. Individuals (n=430) from 4 to 41 mm standard length (SL) were collected in the Río de la Plata estuary (35.45º S, 56.35º W) in March 2006. Length ranges of individual´s developmental stages were associated with the presence of key morphological characters. During early life stages, M. furnieri changes from a big-headed, robust shape larva to a slender and more elongated body form. Most of the morphometric variables showed an inflexion point at 15.2 mm SL, with a 95% confidence interval of 14.0 – 16.4 mm. The anterior part of the body grows faster during early stages, probably related to an intense feeding activity strategy. The completion of pectoral fin rays and the onset of squamation determine the beginning of metamorphosis at 11-12 mm SL. At around 18 mm SL, squamation ends, first barbels develop and the sagittae otolith primordium is closed. The length-at-metamorphosis for M. furnieri was established between 9 to 18 mm SL, since all developmental characters studied highly overlapped at that interval. All those processes are indicative of the beginning of the juvenile period associated to the settlement and the start of a bottom-oriented life-style.


2016 ◽  
Vol 63 (3) ◽  
Author(s):  
M. V. Rohini Krishna ◽  
M. K. Anil ◽  
P. Neethu Raj ◽  
B. Santhosh

Development of the regal demoiselle Neopomacentrus cyanomos (Bleeker, 1856) from egg to maturation and spawning stage is described using hatchery reared specimens. Larval rearing of N. cyanomos was carried out using zooplankton as the starting feed up to the 10th day post-hatch (dph). Larval and post-larval growth was studied for a period of 340 dph. Caudal fin rays began to develop from 8th dph and the larval body depth increased considerably from 9th dph onwards. Towards the 10th dph, at about 5.7 mm total length (TL) half of the specimens underwent notochord flexion. Larvae exhibited decreased transparency with increased pigmentation of the pre-anal body, characterised by presence of stellate melanophores. Towards 15th dph, the pectoral, pelvic, dorsal, anal and caudal fins were visible with fin rays. The soft dorsal fin started showing pigmentation from 20th dph onwards and the spinous dorsal from 30th dph onwards. Towards 30th day, black pigments were found distributed all over the body. Pigmentation steadily increased from 30th day onwards and the juveniles fully attained the adult pattern of body colouration by about 90-100 days. First spawning occurred on the 340th dph at a size of 64-73 mm TL.


2013 ◽  
Vol 11 (2) ◽  
pp. 307-318 ◽  
Author(s):  
Adrian F. Gonzalez-Acosta ◽  
Rocio Rodiles-Hernandez

Eugerres castroaguirrei, new species is described from the río Grijalva-Usumacinta basin of southeastern Mexico and northern Guatemala. Eugerres castroaguirrei and E. mexicanus are distinguishable from their marine estuarine congeners by the dorsal-fin origin posterior to the insertion of the pectoral and pelvic fins, a shorter and broad based supraoccipital crest, and a distinct geographic distribution restricted to freshwater habitats. Eugerres castroaguirrei differs from E. mexicanus by diagnostic characters of the body skeleton: anterior process of supraoccipital convex, infraorbital 1 with foramen, premaxillary ascending process developed with margins curved, pharyngeal plate granular and not serially arranged, and dorsal and anal fin-rays reduced. Likewise, E. castroaguirrei is characterized by an oblong and laterally thicker body (37.6-58.5% HL); greater body depth (33.8-42.1% SL), and eye diameter (23.3-31.6% HL); in addition to 16 significant morphometric characters: length of the second dorsal-fin spine 23.2-34.2% SL; depressed second dorsal-fin spine (extending to base of third to fourth dorsal-fin rays); length of second anal-fin spine 11.1-20.6% SL, depressed second anal-fin spine extending to the base of third to fourth anal-fin rays not reaching the distal point of last anal-fin ray; pelvic-fin spine length 49.7-65.0% in the first pelvic-fin ray length


2016 ◽  
Vol 8 (2) ◽  
pp. 905-909
Author(s):  
Jyotish Barman ◽  
A.K. Jaiswar ◽  
S.K. Chakraborty ◽  
B.K. Bhattacharjya ◽  
Gopalkrishna Gopalkrishna

The present investigation reports the variation observed in morphological traits of an anopthalmic specimen of Sperata seenghala (Sykes, 1839) (168.9 mm in standard length) from Assam. Thirty morphometric and six meristic characters of the abnormal specimen were studied and compared with normal specimens to observe variation in the morpho-meristic traits, if any. The proportionate pre-pectoral length (28.5 mm), length of dorsal fin base (15.0 mm), pelvic fin length (15.5 mm), distance between urino-genital openings and anal fin base (14.0 mm) and body depth at pectoral fin base (12.0 mm) of the abnormal specimen was found to be higher compared to that of the normal specimens (23.8 – 26.5 mm; 12.2 – 14.1 mm; 11.1 – 14.7 mm; 10.9 – 12.4 mm and 8.9 – 9.9 mm, respectively); while the dorsal to adiposedistance (12.8 mm) and body width at cleithrum (41.5 mm) was lower than the normal specimens (13.7 – 16.7 mm and 44.0 – 50.0 mm, respectively). No marked variation was observed in the meristic characters. Pollution due to urban runoff, sewage discharge and oil spill from inland water transport facilities adversely affecting the river water quality could be the reason for such deformity. The overall growth performance of the fish does not seem to be affected by these anomalies.


2014 ◽  
Vol 104 (3) ◽  
pp. 299-307 ◽  
Author(s):  
Francco A. N. de Souza e Lima ◽  
João Luiz Gasparini ◽  
Antonio de Padua Almeida ◽  
Marcos V. C. Vital ◽  
Tamí Mott

Amphisbaena nigricauda Gans, 1966 is a small, poorly known amphisbaenid endemic to the restinga of the states of Espírito Santo and Bahia, Brazil. We analyze 178 specimens collected in Vitória municipality, state of Espírito Santo, Brazil, to investigate whether this species show sexual dimorphism in pre-cloacal pores and in morphological characters. Sex was determined by a ventral incision and direct inspection of gonads. A PCA analysis was performed to generate a general body size measurement. A T test and the non-parametric Mann-Whitney test were used to assess whether this species show sexual dimorphism on five morphometric and five meristic characters, respectively. Sex could not be determined in 36 specimens because they were mutilated in the posterior portion of their bodies. The diagnosis of the species is redefined based on this sample size: the smallest number of body annuli changes from 222 to 192, the number of dorsal and ventral segments in an annulus in the middle of the body changes to 9-11/13-16 (instead of 10/16), and the autotomic tail annulus lies between annulus 7-10 (instead of 6-9). The number of tail annuli remained within the known range of variation of the species (19-24). None of the 80 females analyzed showed pre-cloacal pores, whereas within males 59 out of 62 specimens displayed four and two specimens displayed five pre-cloacal pores. A single male did not possess pre-cloacal pores, but showed irregular scales on its cloacal region. Sex-based difference based on presence or absence of pre-cloacal pores as well as males with wider head was seen in other Neotropical amphisbaenids. However, a pattern of body size differences between males and females has not been identified so far in the few amphisbaenid species studied in this regard. Further studies on this taxonomic group are still needed to elucidate the existence of general patterns of sexual dimorphism and to identify the selective pressures driving these patterns.


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