scholarly journals A new tuskless walrus from the Miocene of Orange County, California, with comments on the diversity and taxonomy of odobenids

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5708 ◽  
Author(s):  
Isaac Magallanes ◽  
James F. Parham ◽  
Gabriel-Philip Santos ◽  
Jorge Velez-Juarbe
Keyword(s):  
Phylogenetic Analysis ◽  
Fossil Record ◽  
Large Time ◽  
Orange County ◽  
Depositional Environments ◽  
East Pacific ◽  
The Pacific ◽  
The Pacific Ocean ◽  
A New Species ◽  
Stratigraphic Uncertainty

We describeTitanotaria orangensis(gen. et. sp. nov.), a new species of walrus (odobenid) from the upper Miocene Oso Member of the Capistrano Formation of Orange County, California. This species is important because: (1) It is one of the best-known and latest-surviving tuskless walruses; (2) It raises the number of reported odobenid taxa from the Oso Member to four species making it one of the richest walrus assemblages known (along with the basal Purisima of Northern California); (3) It is just the second record of a tuskless walrus from the same unit as a tusked taxon. Our phylogenetic analysis placesT. orangensisas sister to a clade that includesImagotaria downsi,Pontolis magnus,Dusignathusspp.,Gomphotaria pugnax, and Odobeninae. We propose new branch-based phylogenetic definitions for Odobenidae, Odobeninae, and a new node-based name (Neodobenia) for the clade that includesDusignathusspp.,G. pugnax, and Odobeninae. A richness analysis at the 0.1 Ma level that incorporates stratigraphic uncertainty and ghost lineages demonstrates maximum peaks of richness (up to eight or nine coeval lineages) near the base of Odobenidae, Neodobenia, and Odobenini. A more conservative minimum curve demonstrates that standing richness may have been much lower than the maximum lineage richness estimates that are biased by stratigraphic uncertainty. Overall the odobenid fossil record is uneven, with large time slices of the record missing on either side of the Pacific Ocean at some times and biases from the preserved depositional environments at other times. We recognize a provisional timescale for the transition of East Pacific odobenid assemblages that include “basal odobenids” (stem neodobenians) from the Empire and older formations (>7 Ma), to a mixture of basal odobenids and neodobenians from the Capistrano and basal Purisima (7–5 Ma), and then just neodobenians from all younger units (<5 Ma). The large amount of undescribed material will add new taxa and range extensions for existing taxa, which will likely change some of the patterns we describe.

scholarly journals Extreme secondary sexual dimorphism in the genus Florarctus (Heterotardigrada: Halechiniscidae)

2021 ◽  
Vol 51 (3) ◽  
Author(s):  
Piotr Gąsiorek ◽  
David Møbjerg Kristensen ◽  
Reinhardt Møbjerg Kristensen
Keyword(s):  
Sexual Dimorphism ◽  
Pacific Ocean ◽  
Barrier Reef ◽  
Queensland Museum ◽  
The Pacific ◽  
Secondary Sexual Dimorphism ◽  
The Pacific Ocean ◽  
A New Species ◽  
Lines Of Evidence ◽  
Secondary Sexual

AbstractSecondary sexual dimorphism in florarctin tardigrades is a well-known phenomenon. Males are usually smaller than females, and primary clavae are relatively longer in the former. A new species Florarctus bellahelenae, collected from subtidal coralline sand just behind the reef fringe of Long Island, Chesterfield Reefs (Pacific Ocean), exhibits extreme secondary dimorphism. Males have developed primary clavae that are much thicker and three times longer than those present in females. Furthermore, the male primary clavae have an accordion-like outer structure, whereas primary clavae are smooth in females. Other species of Florarctus Delamare-Deboutteville & Renaud-Mornant, 1965 inhabiting the Pacific Ocean were investigated. Males are typically smaller than females, but males of Florarctus heimi Delamare-Deboutteville & Renaud-Mornant, 1965 and females of Florarctus cervinus Renaud-Mornant, 1987 have never been recorded. The Renaud-Mornant collection was re-examined, and type series were analysed. Florarctus heimi and F. cervinus were always found together in the coralline sand of Heron Island (Great Barrier Reef). The animals were kept alive and surveyed in the laboratory of the Queensland Museum. All studied individuals of the larger F. heimi (up to ca. 400 μm) were females, and all adults of the smaller F. cervinus (about 170 μm) were males. Males of F. cervinus were observed mating with females of F. heimi. Following those morphological and behavioural lines of evidence, we propose that F. cervinus is a junior synonym of F. heimi. Based on the discovery of dimorphism in F. bellahelenae sp. nov. and the strong sex-related morphological disparities in F. heimi, we suggest that extreme secondary dimorphism may be present in other florarctin arthrotardigrades.

scholarly journals A new species of Leptogorgia (Cnidaria: Anthozoa: Octocorallia) from Golfo Dulce, Pacific, Costa Rica

Zootaxa ◽  
2012 ◽  
Vol 3182 (1) ◽  
pp. 65 ◽  
Author(s):  
ODALISCA BREEDY ◽  
HECTOR M. GUZMAN
Keyword(s):  
New Species ◽  
Costa Rica ◽  
Pacific Coast ◽  
Single Species ◽  
San Jose ◽  
Ongoing Research ◽  
Deep Waters ◽  
The Pacific ◽  
The Pacific Ocean ◽  
A New Species

The description of this single species is necessary to facilitate the publication of ongoing research conducted by Rita Vargas at the Museum of Zoology, University of Costa Rica, dealing with the associated microfauna. Presently 24 species of Leptogorgia have been reported for the eastern Pacific, 13 of which have been found in Costa Rica (Breedy & Cortés 2011). Although octocoral surveys have been conducted as part of biodiversity studies, there is no published information regarding the occurrence of this taxon in Golfo Dulce. Here we describe a new species of Leptogorgia and compare it with other Leptogorgia species with similar characteristics. Golfo Dulce is a bay located on the southern Pacific coast of Costa Rica. It is about 50 km long, 10–15 km wide, and covers an area of approximately 680 km². The inner part of Golfo Dulce has a maximum depth of slightly over 200 m with a 60 m deep sill at the opening to the Pacific Ocean (Cortés 1999). It has been considered a tropical fjord because of the bathymetry and the presence of anoxic deep waters (Cortés 1999, Svendsen et al. 2006). Specimens were collected by Scuba diving, preserved in 70% ethanol or air dried, and treated and identified following the current methodology (Breedy & Guzman 2002). The holotype and paratypes are deposited in the Museo de Zoología, Universidad de Costa Rica (MZUCR, formerly UCR), San José, P.O. Box 11501-2060, Costa Rica.

Records of species of the hippolytid genus Lebbeus White, 1847 (Crustacea: Decapoda: Caridea) from hydrothermal vents in the Pacific Ocean, with descriptions of three new species

Zootaxa ◽  
2012 ◽  
Vol 3241 (1) ◽  
pp. 35 ◽  
Author(s):  
TOMOYUKI KOMAI ◽  
SHINJI TSUCHIDA ◽  
MICHEL SEGONZAC
Keyword(s):  
New Species ◽  
Pacific Ocean ◽  
Hydrothermal Vents ◽  
Okinawa Trough ◽  
East Pacific Rise ◽  
East Pacific ◽  
The Okinawa Trough ◽  
The Pacific ◽  
The Pacific Ocean ◽  
Three New Species

Five species of the hippolytid shrimp genus Lebbeus White, 1847 are reported from various deep-water hydrothermal ventsites in the Pacific Ocean: L. laurentae Wicksten, 2010 from the East Pacific Rise 13°N; L. wera Ahyong, 2009 from theBrothers Seamount, Kermadec Ridge, New Zealand; L. pacmanus sp. nov. from the Manus Basin, Bismarck Sea; L.shinkaiae sp. nov. from the Okinawa Trough, Japan; and L. thermophilus sp. nov. from the Manus and Lau basins, south-western Pacific. Lebbeus laurentae is fully redescribed because the original and subsequent descriptions are not totallydetailed. Differentiating characters among the three new species and close allies are discussed. Previous records of Lebbeus species from hydrothermal vents are reviewed.

A new species of Mysidium (Peracarida: Mysida: Mysidae) from the eastern tropical Pacific

2016 ◽  
Vol 97 (1) ◽  
pp. 113-117
Author(s):  
Manuel Ortiz ◽  
Michel E. Hendrickx ◽  
Ignacio Winfield
Keyword(s):  
New Species ◽  
Pacific Ocean ◽  
Tropical Pacific ◽  
The Other ◽  
Eastern Tropical Pacific ◽  
The Pacific ◽  
Appendix Masculina ◽  
The Pacific Ocean ◽  
A New Species

A new species of Mysidium from the eastern tropical Pacific, Mexico, is described, representing the second species of this genus described for the Pacific Ocean and the eighth species reported worldwide. Mysidium pumae sp. nov. is distinguished from the other species of the genus by several characters including: the lanceolate appendix masculina, 3× as long as wide, tapering distally, with a distal tuft of 16 setae and an inner proximal tuft of more than 30 setae, the male pleopod 4 with endopod bearing 3 setae, the exopod with 4 articles, the modified seta from article 3 of the exopod bifid, telson 2.3× as long as wide, distally concave. A table with the main differences among all the known species in the genus is provided.

First record of Hyalascus (Hexactinellida: Rossellidae) from the Indian Ocean, with description of a new species from a volcanic seamount in the Andaman Sea

Zootaxa ◽  
2010 ◽  
Vol 2667 (1) ◽  
pp. 64 ◽  
Author(s):  
SABYASACHI SAUTYA ◽  
KONSTANTIN R. TABACHNICK ◽  
BABAN INGOLE
Keyword(s):  
New Species ◽  
Pacific Ocean ◽  
Indian Ocean ◽  
First Record ◽  
Andaman Sea ◽  
The Pacific ◽  
The Indian Ocean ◽  
The Pacific Ocean ◽  
Back Arc ◽  
A New Species

A new species of Hyalascus is described from the submarine volcanic crater seamount of Andaman Back-arc Basin, Indian Ocean. The genus was previously known in the Pacific Ocean only.

A new species ofTriptolemma(Porifera: Pachastrellidae) from the Pacific Ocean with a revision of the genus

2010 ◽  
Vol 91 (2) ◽  
pp. 329-338 ◽  
Author(s):  
Marco Bertolino ◽  
D. Pica ◽  
G. Bavestrello ◽  
N. Iwasaki ◽  
B. Calcinai
Keyword(s):  
New Species ◽  
Pacific Ocean ◽  
Chemical Dissolution ◽  
Typical Pattern ◽  
Etching Mechanism ◽  
The Pacific ◽  
The Pacific Ocean ◽  
First Time ◽  
A New Species ◽  
Thick Crust

A new species,T. strongylatasp. nov. is described on the basis of material collected from the Pacific Ocean. The new species is characterized by the presence of sinuous strongyles. Moreover the incomplete description ofT. simplex(Sarà, 1959) is implemented on the basis of new abundant material allowing, for the first time, the complete description of the skeleton of aTriptolemmaspecies and the detecting of the presence of monaxonic spicules in the spicular complement of the genus. The skeleton is composed of a thick crust of disorderly arranged mesotriaenes and scattered microscleres, supported by diverging spicule tracts formed by oxeas towards the surface. Both species were recorded associated to boring sponges(SpiroxyaandCliona)in excavations of the calcareous scleraxis of precious corals or in organogenic concretions. In the cavities where the tissue ofTriptolemmawas recorded the wall of the excavation partially lost its typical pattern characterized by ovoid scars and became irregularly eroded. Our hypothesis is thatTriptolemmainsinuates inside the erosions produced by other sponges and it is able to enlarge them by an etching mechanism based on chemical dissolution only.

Calicium sequoiae, a new lichen species from north-western California, USA

2008 ◽  
Vol 40 (3) ◽  
pp. 185-194 ◽  
Author(s):  
Cameron B. WILLIAMS ◽  
Leif TIBELL
Keyword(s):  
Phylogenetic Analysis ◽  
New Species ◽  
Pacific Northwest ◽  
Its Region ◽  
Sequoia Sempervirens ◽  
Old Growth ◽  
The Pacific ◽  
Secondary Substance ◽  
North Western ◽  
A New Species

Abstract:We describe Calicium sequoiae as a new species of lichenized Ascomycota from north-western California, USA. The species is distinguished morphologically from other known members of Calicium by its stalks that react I+ blue, mature ascospores that are ornamented with spiral ridges, and apothecia that produce prominent white pruina. It is also the only Calicium known to produce thamnolic acid as a major secondary substance. Sequences from the ITS-region showed C. sequoiae to be unique among calicioid Physciaceae, and phylogenetic analysis positioned it close to C. adspersum, C. chlorosporum, C. lenticulare, Cyphelium notarisii, and C. tigillare. Thus far, Calicium sequoiae has been collected only from old-growth redwood (Sequoia sempervirens) forests, where it occurred on thick, fibrous bark of large redwood trees. A key to the 12 species of Calicium known from the Pacific Northwest is provided.

scholarly journals Tosanoides aphrodite, a new species from mesophotic coral ecosystems of St. Paul’s Rocks, Mid Atlantic Ridge (Perciformes, Serranidae, Anthiadinae)

ZooKeys ◽  
2018 ◽  
Vol 786 ◽  
pp. 105-115 ◽  
Author(s):  
Hudson T. Pinheiro ◽  
Claudia Rocha ◽  
Luiz A. Rocha
Keyword(s):  
New Taxon ◽  
Undescribed Species ◽  
Mesophotic Coral Ecosystems ◽  
Dorsal Fin ◽  
Unknown Species ◽  
The Pacific ◽  
Fin Rays ◽  
Mid Atlantic Ridge ◽  
The Pacific Ocean ◽  
A New Species

During a recent expedition to St. Paul’s Rocks, Atlantic Ocean, a distinctive and previously unknown species of Anthiadinae was collected at a depth of 120 m. A genetic analysis indicated the undescribed species is a member of the genus Tosanoides, which was only known to occur in the Pacific Ocean. This new taxon is distinguishable from all other Tosanoides species by the following combination of characters: soft dorsal fin rays 15–16; anal fin rays 9; ventral scale rows 9–10; last dorsal spine the longest (instead first through fourth). Here Tosanoidesaphroditesp. n. is described and illustrated, only known from St. Paul’s Rocks.

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