Two new miniature silverside fishes of the genus Membras Bonaparte (Atheriniformes, Atherinopsidae) from the Tropical North Atlantic Ocean

Zootaxa ◽  
2020 ◽  
Vol 4852 (2) ◽  
pp. 191-202
Author(s):  
BARRY CHERNOFF ◽  
ANTONIO MACHADO-ALLISON ◽  
JENNIFER ESCOBEDO ◽  
MICHAEL FREIBURGER ◽  
ELIJAH HENDERSON ◽  
...  

Two new species of miniature silverside fishes are described from coastal habitats in the tropical Atlantic: Membras pygmaea sp. nov., from Brus Lagoon, Honduras, and M. procera sp. nov., from the Gulf of Urabá, Colombia. These new species belong to the martinica species-group within the genus Membras Bonaparte. The monophyletic martinica species-group (see below) contains four additional species, all coastal, marine that extend from the east coast of North America to São Paolo State, Brazil. Within the martinica species-group, all but M. martinica are miniature species, ranging from 41–60 mm SL. The smallest species, M. pygmaea sp. nov., is mature at 24 mm SL. A geometric morphometric analysis shows: (i) each species of the martinica species-group occupies its own portion of shape space; and (ii) none of the miniature species possess the shapes of small immature M. martinica. While some of the literature suggests that miniaturization may involve paedomorphosis, our results show that the miniatures accelerate to adult body forms. 

2013 ◽  
Vol 82 (4) ◽  
pp. 353-363 ◽  
Author(s):  
Bogusław Soszyński ◽  
Lukasz Emil Mielczarek ◽  
Adam Tofilski

ABSTRACT Both sexes of Dasysyrphus neovenustus sp. n. are described and illustrated, and the characters separating them from the similar D. venustus are given. The distinctiveness of the new species is confirmed also by geometric morphometric analysis of the wing venation. The new species is known from Poland and Siberia (Russia).


2020 ◽  
Vol 96 (2) ◽  
pp. 281-296
Author(s):  
Heather Judkins ◽  
Annie Lindgren ◽  
Roger Villanueva ◽  
Kristine Clark ◽  
Michael Vecchione

Currently, three species in the squid family Bathyteuthidae are recognized as valid: Bathyteuthis abyssicola Hoyle, 1885, Bathyteuthis bacidifera Roper, 1968, and Bathyteuthis berryi Roper, 1968. Using morphology and DNA sequencing (COI, 16S), we discovered three additional species of bathyteuthids collected from the North Atlantic Ocean and adjacent basins between 2009 and 2018. Two of the newly discovered species share the absence of arm-base photophores as well as differences in arm-sucker and buccallappet sucker counts. In the third species, the adult female individual has arm-base photophores but the two juveniles (sex undetermined) do not. All examined individuals of this species exhibited <1% divergence rate for the COI locus. We describe and name the three new species based on both morphological and molecular characters.


1993 ◽  
Vol 71 (5) ◽  
pp. 997-1002 ◽  
Author(s):  
Dale R. Calder

Bougainvillia aberrans n.sp. is described from Bermuda in the western North Atlantic Ocean. Specimens were collected at a depth of 150 fathoms (274 m) from the polypropylene buoy line of a crab trap. The hydroid colony of B. aberrans is erect, with a polysiphonic hydrocaulus, a smooth to somewhat wrinkled perisarc, hydranths having a maximum of about 16 tentacles, and medusa buds arising only from hydranth pedicels. Medusae liberated in the laboratory from these hydroids differ from all other known species of the genus in having a long, spindle-shaped manubrium, lacking oral tentacles, having marginal tentacles reduced to mere stubs, and being very short-lived (surviving for a few hours at most). Gonads develop in medusa buds while they are still attached to the hydroids, and gametes are shed either prior to liberation of the medusae or shortly thereafter. The eggs are surrounded by an envelope bearing nematocysts (heterotrichous microbasic euryteles). The cnidome of both hydroid and medusa stages consists of desmonemes and heterotrichous microbasic euryteles. The diagnosis of the genus Bougainvillia is modified to accommodate this new deep-water species.


2015 ◽  
Vol 12 (8) ◽  
pp. 2597-2605 ◽  
Author(s):  
J. Karstensen ◽  
B. Fiedler ◽  
F. Schütte ◽  
P. Brandt ◽  
A. Körtzinger ◽  
...  

Abstract. Here we present first observations, from instrumentation installed on moorings and a float, of unexpectedly low (<2 μmol kg−1) oxygen environments in the open waters of the tropical North Atlantic, a region where oxygen concentration does normally not fall much below 40 μmol kg−1. The low-oxygen zones are created at shallow depth, just below the mixed layer, in the euphotic zone of cyclonic eddies and anticyclonic-modewater eddies. Both types of eddies are prone to high surface productivity. Net respiration rates for the eddies are found to be 3 to 5 times higher when compared with surrounding waters. Oxygen is lowest in the centre of the eddies, in a depth range where the swirl velocity, defining the transition between eddy and surroundings, has its maximum. It is assumed that the strong velocity at the outer rim of the eddies hampers the transport of properties across the eddies boundary and as such isolates their cores. This is supported by a remarkably stable hydrographic structure of the eddies core over periods of several months. The eddies propagate westward, at about 4 to 5 km day−1, from their generation region off the West African coast into the open ocean. High productivity and accompanying respiration, paired with sluggish exchange across the eddy boundary, create the "dead zone" inside the eddies, so far only reported for coastal areas or lakes. We observe a direct impact of the open ocean dead zones on the marine ecosystem as such that the diurnal vertical migration of zooplankton is suppressed inside the eddies.


2018 ◽  
Vol 15 (19) ◽  
pp. 5951-5968 ◽  
Author(s):  
Sergio Balzano ◽  
Julie Lattaud ◽  
Laura Villanueva ◽  
Sebastiaan W. Rampen ◽  
Corina P. D. Brussaard ◽  
...  

Abstract. Long chain alkyl diols (LCDs) are widespread in the marine water column and sediments, but their biological sources are mostly unknown. Here we combine lipid analyses with 18S rRNA gene amplicon sequencing on suspended particulate matter (SPM) collected in the photic zone of the western tropical North Atlantic Ocean at 24 stations to infer relationships between LCDs and potential LCD producers. The C30 1,15-diol was detected in all SPM samples and accounted for >95 % of the total LCDs, while minor proportions of C28 and C30 1,13-diols, C28 and C30 1,14-diols, as well as C32 1,15-diol were found. The concentration of the C30 and C32 diols was higher in the mixed layer of the water column compared to the deep chlorophyll maximum (DCM), whereas concentrations of C28 diols were comparable. Sequencing analyses revealed extremely low contributions (≈0.1 % of the 18S rRNA gene reads) of known LCD producers, but the contributions from two taxonomic classes with which known producers are affiliated, i.e. Dictyochophyceae and Chrysophyceae, followed a trend similar to that of the concentrations of C30 and C32 diols. Statistical analyses indicated that the abundance of 4 operational taxonomic units (OTUs) of the Chrysophyceae and Dictyochophyceae, along with 23 OTUs falling into other phylogenetic groups, were weakly (r≤0.6) but significantly (p value <0.01) correlated with C30 diol concentrations. It is not clear whether some of these OTUs might indeed correspond to C28−32 diol producers or whether these correlations are just indirect and the occurrence of C30 diols and specific OTUs in the same samples might be driven by other environmental conditions. Moreover, primer mismatches were unlikely, but cannot be excluded, and the variable number of rRNA gene copies within eukaryotes might have affected the analyses leading to LCD producers being undetected or undersampled. Furthermore, based on the average LCD content measured in cultivated LCD-producing algae, the detected concentrations of LCDs in SPM are too high to be explained by the abundances of the suspected LCD-producing OTUs. This is likely explained by the slower degradation of LCDs compared to DNA in the oxic water column and suggests that some of the LCDs found here were likely to be associated with suspended debris, while the DNA from the related LCD producers had been already fully degraded. This suggests that care should be taken in constraining biological sources of relatively stable biomarker lipids by quantitative comparisons of DNA and lipid abundances.


Author(s):  
Les Watling

Exploration of the New England and Corner Rise Seamounts produced four new species of chrysogorgiid octocorals with the spiral iridogorgiid growth form. Three species are described as new in the genus Iridogorgia and one is described in the new genus Rhodaniridogorgia. Both genera have representatives in the Atlantic and Pacific Oceans. Iridogorgia magnispiralis sp. nov., is one of the largest octocorals encountered in the deep sea and seems to be widespread in the Atlantic.


PLoS ONE ◽  
2019 ◽  
Vol 14 (9) ◽  
pp. e0222584 ◽  
Author(s):  
Anouck Ody ◽  
Thierry Thibaut ◽  
Léo Berline ◽  
Thomas Changeux ◽  
Jean-Michel André ◽  
...  

1972 ◽  
Vol 50 (4) ◽  
pp. 371-383 ◽  
Author(s):  
Diana R. Laubitz ◽  
Eric L. Mills

Five species of Caprellidea (Amphipoda) occur on a benthic transect between Gay Head, Massachusetts and Bermuda. Three species, Caprella rinki Stephensen, Mayerella limicola Huntsman, and Proaeginina norvegica (Stephensen) are refigured and redescribed. A new species of Thorina and a new genus and species are described from bathyal and abyssal depths. All five species are arctic–boreal in affinities and may be expected to range south only to Cape Hatteras on the continental slope, but much farther south at abyssal depths.


Sign in / Sign up

Export Citation Format

Share Document