Validity, Identification, and Distribution of the Roundscale Spearfish, Tetrapturus georgii (Teleostei: Istiophoridae): Morphological and Molecular Evidence
The roundscale spearfish, Tetrapturus georgii Lowe, 1840, is known only from four specimens from the Mediterranean and eastern North Atlantic. Additional specimens have not been identified since 1961, making the validity and distribution of this species unclear. Analysis of 16 billfish specimens fro...
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ftnsoutheastern:oai:nsuworks.nova.edu:occ_facarticles-1384 2023-05-15T17:27:21+02:00 Validity, Identification, and Distribution of the Roundscale Spearfish, Tetrapturus georgii (Teleostei: Istiophoridae): Morphological and Molecular Evidence Shivji, Mahmood S. Magnussen, Jennifer E. Beerkircher, Lawrence R. Hinteregger, George Lee, Dennis W. Serafy, Joseph E. Prince, Eric D. 2006-11-01T08:00:00Z application/pdf https://nsuworks.nova.edu/occ_facarticles/374 https://nsuworks.nova.edu/cgi/viewcontent.cgi?article=1384&context=occ_facarticles unknown NSUWorks https://nsuworks.nova.edu/occ_facarticles/374 https://nsuworks.nova.edu/cgi/viewcontent.cgi?article=1384&context=occ_facarticles Marine & Environmental Sciences Faculty Articles Genetics and Genomics Marine Biology Oceanography and Atmospheric Sciences and Meteorology article 2006 ftnsoutheastern 2022-04-10T21:27:51Z The roundscale spearfish, Tetrapturus georgii Lowe, 1840, is known only from four specimens from the Mediterranean and eastern North Atlantic. Additional specimens have not been identified since 1961, making the validity and distribution of this species unclear. Analysis of 16 billfish specimens from the western North Atlantic on the basis of scale morphology, anus position, and mitochondrial DNA confirms the validity of this species and extends its distribution. Mid-lateral scales are soft, notably rounded anteriorly, and bear 2–3 points distinct from those of the sympatric longbill spearfish (Tetrapturus pfluegeri Robins and de Sylva, 1963) and white marlin (Tetrapturus albidus Poey, 1860). Position of anus relative to first anal fin and a related morphometric ratio (distance from anus to first anal fin origin: height of first anal fin) are intermediate between T. pfluegeri and T. albidus. These characteristics match those described by Robins (1974) from the four eastern North Atlantic specimens of T. georgii. The mitochondrial ND4L, ND4, and cyt b gene sequences strongly support reciprocal monophyly of the western North Atlantic specimens relative to other Atlantic istiophorids. The difficulty in distinguishing between morphologically similar T. georgii and T. albidus in the field and the previously unrecognized presence of T. georgii in the western North Atlantic has implications for stock assessments of T. albidus, a species that is severely overfished. Article in Journal/Newspaper North Atlantic Nova Southeastern University: NSU Works Lowe ENVELOPE(-30.309,-30.309,-80.537,-80.537) |
institution |
Open Polar |
collection |
Nova Southeastern University: NSU Works |
op_collection_id |
ftnsoutheastern |
language |
unknown |
topic |
Genetics and Genomics Marine Biology Oceanography and Atmospheric Sciences and Meteorology |
spellingShingle |
Genetics and Genomics Marine Biology Oceanography and Atmospheric Sciences and Meteorology Shivji, Mahmood S. Magnussen, Jennifer E. Beerkircher, Lawrence R. Hinteregger, George Lee, Dennis W. Serafy, Joseph E. Prince, Eric D. Validity, Identification, and Distribution of the Roundscale Spearfish, Tetrapturus georgii (Teleostei: Istiophoridae): Morphological and Molecular Evidence |
topic_facet |
Genetics and Genomics Marine Biology Oceanography and Atmospheric Sciences and Meteorology |
description |
The roundscale spearfish, Tetrapturus georgii Lowe, 1840, is known only from four specimens from the Mediterranean and eastern North Atlantic. Additional specimens have not been identified since 1961, making the validity and distribution of this species unclear. Analysis of 16 billfish specimens from the western North Atlantic on the basis of scale morphology, anus position, and mitochondrial DNA confirms the validity of this species and extends its distribution. Mid-lateral scales are soft, notably rounded anteriorly, and bear 2–3 points distinct from those of the sympatric longbill spearfish (Tetrapturus pfluegeri Robins and de Sylva, 1963) and white marlin (Tetrapturus albidus Poey, 1860). Position of anus relative to first anal fin and a related morphometric ratio (distance from anus to first anal fin origin: height of first anal fin) are intermediate between T. pfluegeri and T. albidus. These characteristics match those described by Robins (1974) from the four eastern North Atlantic specimens of T. georgii. The mitochondrial ND4L, ND4, and cyt b gene sequences strongly support reciprocal monophyly of the western North Atlantic specimens relative to other Atlantic istiophorids. The difficulty in distinguishing between morphologically similar T. georgii and T. albidus in the field and the previously unrecognized presence of T. georgii in the western North Atlantic has implications for stock assessments of T. albidus, a species that is severely overfished. |
format |
Article in Journal/Newspaper |
author |
Shivji, Mahmood S. Magnussen, Jennifer E. Beerkircher, Lawrence R. Hinteregger, George Lee, Dennis W. Serafy, Joseph E. Prince, Eric D. |
author_facet |
Shivji, Mahmood S. Magnussen, Jennifer E. Beerkircher, Lawrence R. Hinteregger, George Lee, Dennis W. Serafy, Joseph E. Prince, Eric D. |
author_sort |
Shivji, Mahmood S. |
title |
Validity, Identification, and Distribution of the Roundscale Spearfish, Tetrapturus georgii (Teleostei: Istiophoridae): Morphological and Molecular Evidence |
title_short |
Validity, Identification, and Distribution of the Roundscale Spearfish, Tetrapturus georgii (Teleostei: Istiophoridae): Morphological and Molecular Evidence |
title_full |
Validity, Identification, and Distribution of the Roundscale Spearfish, Tetrapturus georgii (Teleostei: Istiophoridae): Morphological and Molecular Evidence |
title_fullStr |
Validity, Identification, and Distribution of the Roundscale Spearfish, Tetrapturus georgii (Teleostei: Istiophoridae): Morphological and Molecular Evidence |
title_full_unstemmed |
Validity, Identification, and Distribution of the Roundscale Spearfish, Tetrapturus georgii (Teleostei: Istiophoridae): Morphological and Molecular Evidence |
title_sort |
validity, identification, and distribution of the roundscale spearfish, tetrapturus georgii (teleostei: istiophoridae): morphological and molecular evidence |
publisher |
NSUWorks |
publishDate |
2006 |
url |
https://nsuworks.nova.edu/occ_facarticles/374 https://nsuworks.nova.edu/cgi/viewcontent.cgi?article=1384&context=occ_facarticles |
long_lat |
ENVELOPE(-30.309,-30.309,-80.537,-80.537) |
geographic |
Lowe |
geographic_facet |
Lowe |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Marine & Environmental Sciences Faculty Articles |
op_relation |
https://nsuworks.nova.edu/occ_facarticles/374 https://nsuworks.nova.edu/cgi/viewcontent.cgi?article=1384&context=occ_facarticles |
_version_ |
1766119400368242688 |