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Gomez S.,Institute Ciencias del Mar y Limnologia | Ingole B.,National Institute of Oceanography of India | Sawant M.,National Institute of Oceanography of India | Singh R.,National Institute of Oceanography of India
Proceedings of the Biological Society of Washington | Year: 2013

A new species of harpacticoid copepod, Cletocamptus goenchim sp. nov., was found in the mouth of the Mandovi estuary, Goa, India. This species seems to be the same reported in 1979 from Lake Kolleru (east coast of India) as C. deitersi, but until new specimens are studied, the 1979 record will remain as doubtful. The new species seems to be related to C. stimpsoni. They can be separated by the armature of the mandibular palp, the shape of the outer element of basis of P2, the ornamentation of the posterior margin of cephalothorax, pro-, and urosomites, and anal operculum of both male and female, the armature formula of male P5EXP, the armature formula of the male P2ENP2, and the relative length and shape of the inner apophysis of the male P3ENP2. Some comments on specimens of Cletocamptus from Korea and China are given.

Gomez S.,Institute Ciencias del Mar y Limnologia | Carrasco N.K.,University of KwaZulu - Natal | Morales-Serna F.N.,National Autonomous University of Mexico
ZooKeys | Year: 2012

A new species of the genus Nitocra Boeck, 1865, Nitocra taylori sp. n. is described from the St Lucia Estuary, Africa's largest estuarine lake. It is also suggested that Nitocra sewelli husmanni Kunz, 1976 and N. reducta fluviatilis Galhano, 1968 are granted full species rank as N. husmanni stat. n. Kunz, 1976 and N. fluviatilis stat. n. Galhano, 1968. Nitocra taylori sp. n. appears to be closely related to N. husmanni. Unfortunately, the original description of the micro-characters of the species lacks the detail needed to make reliable comparisons between species of the genus Nitocra. The main differences observed are the number of spinules along the posterior margin of the anal operculum, length ratio of the exopod and endopod of the first swimming leg, shape of the outer spine on the male third endopodal segment of the third swimming leg, number of segments of the male antennule, relative length of the setae on the male baseoendopod of the fifth leg, shape of the male exopod of the fifth leg, relative length of the two setae of the male sixth leg, and shape of the female baseoendopod of the fifth leg. The current distribution of N. taylori sp. n. is limited to the lake part of the estuary, an area which is most severely affected by the current freshwater deprivation crisis. During closed mouth conditions, these regions (South/North Lake and False Bay) are characterized by low water levels, high salinities and high turbidity levels. This suggests that N. taylori sp. n. may favor these environmental conditions and the significant correlations found between the abundance of N. taylori sp. n. and salinity and turbidity confirm this to a degree. Nitocra taylori sp. n. individuals are also able to withstand a wide range of fluctuations. They were recorded at turbidities ranging from 2 to 102 NTU, temperatures from 20.9 to 34.8 °C and salinity levels ranging from 9.81 to 53.7 psu. However, in the current state of the system, salinity and temperature levels in the northern regions frequently exceed this value. Continued freshwater deprivation may, therefore, further limit the distribution range of this species. © Samuel Gómez et al.

Kovacs J.M.,Nipissing University | Jiao X.,Nipissing University | Flores-de-Santiago F.,University of Western Ontario | Zhang C.,Algoma University | Flores-Verdugo F.,Institute Ciencias del Mar y Limnologia
International Journal of Remote Sensing | Year: 2013

Relationships were assessed between mangrove structural data (leaf area index (LAI), stem density, basal area, diameter at breast height (DBH)) collected from 61 stands located in a black mangrove (Avicennia germinans)-dominated forest and both single polarized ultra-fine (3 m) and multipolarized fine beam (8 m) Radarsat-2 C-band synthetic aperture radar (SAR) data. The stands examined included representatives from the four types of mangroves that typify this degraded system, specifically: predominantly dead mangrove, poor-condition mangrove, healthy dwarf mangrove, and tall healthy mangrove. The results indicate that the selection of the spatial resolution (3 m vs. 8 m) of the incidence angle (27-39°) and the polarimetric mode greatly influence the relationship between the SAR and mangrove structural data. Moreover, the extent of degradation, i.e. whether dead stands are considered, also determines the strength of the relationships between the various SAR and mangrove parameters. When dead stands are included, the strongest overall relationships between the ultra-fine backscatter (incidence angle of ∼32°) and the various structural parameters were found using the horizontal-horizontal (HH) polarization/horizontal-vertical (HV) polarization ratio. However, if the dead stands are not included, then significant relationships with the ultra-fine data were only calculated with the HH data. Similar results were observed using the corresponding incidence angle (∼33°) of the fine beam data. When a shallower incidence angle was considered (∼39°), fewer and weaker relationships were calculated. Moreover, no significant relationships were observed if the dead stands were excluded from the sample at this incidence angle. The highest correlation coefficients using the steepest incidence (∼27°) were found with the co-polarized (HH, vertical-vertical (VV) polarization) modes. Several polarimetric parameters (entropy, pedestal height, surface roughness, alpha angle) based on the decomposition of the scattering matrix of the fine beam mode at this incidence angle were also found to be significantly correlated to mangrove structural data. The highest correlation (R = 0.71) was recorded for entropy and LAI. When the dead stands were excluded, volume scattering was found to be the most significant polarimetric parameter. Finally, multiple regression models, based on texture measures derived from both the grey level co-occurrence matrix (GLCM) and the sum and difference histogram (SADH) of the ultra-fine data, were developed to estimate mangrove parameters. The results indicate that only models derived from the HH data are significant and that several of these were strong predictors of all but stem density. © 2013 Copyright 2013 Taylor & Francis.

Galvan-Tirado C.,Institute Ciencias del Mar y Limnologia | Hinojosa-Alvarez S.,Institute Ciencias del Mar y Limnologia | Diaz-Jaimes P.,Institute Ciencias del Mar y Limnologia | Garcia-De-Leon F.J.,National Polytechnic Institute of Mexico
Mitochondrial DNA | Year: 2016

The silky shark mitogenome (GeneBank accession number KF801102) has a total length of 17,774 bp, the base composition of the genomes was as follows: A (31.36%), T (30.18%), C (25.27%) and G (13.17%), which demonstrated an A + T-rich feature (61.64%), similar to other elasmobranch mitogenomes. The mitochondrial genome contained 13 protein-coding genes and 23 tRNA genes. The tRNA genes ranged from 70 to 72 bp. The gene order was the same as in other vertebrates and teleosts. © 2014 Informa UK Ltd.

Hendrickx M.E.,Institute Ciencias del Mar y Limnologia | Parente M.A.,Institute Ciencias del Mar y Limnologia | Serrano D.,Autonomous University of Sinaloa
Hidrobiologica | Year: 2011

Specimens of galatheids Janetogalathea californiensis (Benedict, 1902) were collected in the northern portion of the Central Gulf of California and represent the third record for this species in the area. Illustrations of the material collected in the Gulf of California are provided and some differences are noted when compared to the description of the paralectotypes. Depth range of the species is discussed and set at 87-786 m. The presence of a wide and deep Oxygen Minimum Zone in the area is believed to limit the dispersion of J. californiensis to the south and to deeper water of the gulf.

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