Hydrological features above a Southern Ocean seamount inhibit larval dispersal and promote speciation: evidence from the bathyal mytilid Dacrydium alleni sp. nov. (Mytilidae: Bivalvia)

first_imgThe Maud Rise seamount (65°07.80′S 2°39.60′E), a distinct habitat in the Southern Ocean, was studied during the ANDEEP-SYSTCO expedition in 2007–2008 to describe its unique benthic assemblage, characterised by higher biomass and lower diversity than other SO locations. Epibenthic sledge deployments during the expedition revealed exceptionally high abundances of the small bivalve genus Dacrydium with a total of 516 specimens collected from this seamount, resembling up to 1860 bivalve individuals per 1000 m−2. The Dacrydium specimens were examined for taxonomic identification, population and reproductive biology. Shell and soft part morphology as well as life history characteristics were compared with all known congeners for which data are available. Hinge dentition, prodissoconch size and adult gill structure are notably different, supporting classification as a separate species, herein formally described as Dacrydium alleni sp. nov. Dacrydium alleni sp. nov. produces lecithotrophic larvae, capable of long-distance dispersal, yet is apparently restricted to the Maud Rise area, supporting the hypothesis that larval dispersal at isolated seamounts may be constrained by hydrographic rather than biological features. In addition to providing insight into the benthic assemblage at Maud Rise, this work also summarises the current taxonomic status of the genus Dacrydium in the Southern Ocean.last_img read more

Dodgers reliever Tom Koehler will be out indefinitely with shoulder strain

first_imgGLENDALE, Ariz. – Whatever role Tom Koehler was going to fill in the Dodgers’ bullpen, he won’t be filling it any time soon.Koehler was diagnosed with a mild anterior capsule strain in his right shoulder and will be sidelined indefinitely.“It all depends on how everything works,” Koehler said of the recovery time for his injury. “Could be weeks, could be months. Right now, it is a little bit of an unknown.”Koehler said the injury is a “milder version” of the injury that left-hander Julio Urias underwent surgery for last summer. Urias had a tear in his shoulder capsule and will be sidelined for 12 to 14 months. Koehler said surgery was not raised as a possibility in his case. Newsroom GuidelinesNews TipsContact UsReport an Error “That word wasn’t even mentioned,” Koehler said. “I think that’s one of the reasons I’m kind of okay today, kind of upbeat. I don’t know how long it’s going to take. But the surgery option was not mentioned and I will be pitching again this year. I just don’t know when.”The 31-year-old Koehler was signed by the Dodgers in December as a conversion candidate after spending six seasons in the majors with the Miami Marlins and Toronto Blue Jays primarily as a starting pitcher. He was expected to pitch high-leverage situations out of the bullpen for the Dodgers this season.“It doesn’t change my goal for the season. It just delays it a little bit,” said Koehler who signed a one-year, $2 million contract. “I came here to help this team win the World Series. If that starts a little later in the season, so be it. Hopefully, the impact can be made on the back end or in the middle of the year. Hit the ground running because this is a good team here.“They’re going to be able to pick up the slack for sure. My goal right now is to get back and contribute to winning that championship.”Koehler said he felt fine when he entered Friday’s game in the third inning. He gave up a home run to the first batter he faced and began to feel discomfort in his biceps.center_img “I got in the game and threw a couple pitches and just wasn’t feeling right,” Koehler said. “But I’ve pitched for awhile and I’ve pitched through things before where it’s kind of one pitch you feel something then two pitches later it’s gone. This wasn’t the case. It’s like it just kind of progressively got a little bit worse.“Originally, I was supposed to go two innings yesterday so in my head I was thinking, I’m just going to get through this one and then tell them, ‘Hey, something doesn’t feel right.’ But it got to the point where I knew I couldn’t keep going.”He left the game after facing four batters and underwent an MRI that revealed the capsule strain. Koehler missed over a month of last season with bursitis in the same shoulder but said that was unrelated to this injury.“It’s not the way I’d like my tenure as a Dodger to start, two weeks in,” Koehler said. “But (stuff) happens.”last_img read more