التفاصيل البيبلوغرافية
| العنوان: |
A combined morphological and molecular approach to Nitzschia varelae sp. nov., with discussion of symmetry in Bacillariaceae. |
| المؤلفون: |
Carballeira, Rafael1 (AUTHOR) rafael.carballeira@usc.e, Trobajo, Rosa2 (AUTHOR), Leira, Manel3,4 (AUTHOR), Benito, Xavier2,5 (AUTHOR), Sato, Shinya6 (AUTHOR), Mann, David G.2,7 (AUTHOR) |
| المصدر: |
European Journal of Phycology. Aug2017, Vol. 52 Issue 3, p342-359. 18p. |
| مصطلحات موضوعية: |
*NITZSCHIA, *BACILLARIACEAE, *DIATOMS, *DIATOM frustules, *RECOMBINANT DNA |
| مستخلص: |
A previously unknown member of the Bacillariaceae was discovered almost simultaneously in four different brackish coastal wetlands on the Atlantic and Mediterranean coasts of the Iberian Peninsula. It appears to tolerate a wide range of salinities but was never common in samples where it occurred. The frustules were consistently hantzschioid (i.e. with the raphe systems always on the same side of the frustule) and the valve outline was asymmetrical about the apical plane, two features that have until recently been considered characteristic ofHantzschia. Molecular phylogenies based onrbcL and LSU rDNA indicated, however, that the new species does not belong inHantzschiabut among the several disparate lineages that comprise the paraphyletic genusNitzschia. This finding, coupled with the recent discovery of other diatoms with constant hantzschioid symmetry but with a morphology very similar to the type species ofNitzschia, is discussed in relation to the status and characterization ofHantzschiaas an independent genus. It is concluded that, while a core of hantzschioid species may exist that can be classified together, corresponding to the traditional understanding of the genusHantzschia, there is no single morphological feature common to all of them that can be used to diagnose the group and differentiate it from the various hantzschioid lineages that are separate from trueHantzschiaand currently placed in e.g.NitzschiaorCymbellonitzschia. Testing whether a hantzschioid species does or does not belong toHantzschiawill in many cases require molecular evidence. Although the new coastal species does not belong to the same lineage as the type species ofNitzschia, N. sigmoidea, it is described for the moment asN. varelaeCarballeira, D.G. Mann & Trobajo,sp. nov., until there is a better understanding of generic limits in the Bacillariaceae following a wider molecular and morphological survey of that family. [ABSTRACT FROM AUTHOR] |
| قاعدة البيانات: |
Academic Search Index |