| Title | Intraspecific morphological variation with biometry of Distephanus speculum (Silicoflagellata) |
| Author | Tsutsui, H.; Takahashi, K.; Nishida, S.; Nishiwaki, N. |
| Author Affil | Tsutsui, H., Kyushu University, Department of Earth and Planetary Sciences, Fukuoka, Japan. Other: Nara University, Japan; Nara University of Education, Japan |
| Source | Marine Micropaleontology, 72(3-4), p.239-250, . Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0377-8398 |
| Publication Date | Sept. 2009 |
| Notes | In English. Based on Publisher- supplied data GeoRef Acc. No: 297350 |
| Index Terms | Deep Sea Drilling Project--DSDP Site 397; Deep Sea Drilling Project--Leg 34; Atlantic Ocean--North Atlantic; Pacific Ocean- -Southeast Pacific; Southern Ocean; algae; Atlantic Ocean; biometry; biostratigraphy; Cenozoic; Deep Sea Drilling Project; Distephanus speculum; DSDP Site 397; East Pacific; Invertebrata; IPOD; Leg 34; Leg 47; living taxa; microfossils; morphology; nannofossils; Neogene; North Atlantic; Pacific Ocean; Plantae; Protista; quantitative analysis; Silicoflagellata; size; South Pacific; Southeast Pacific; statistical analysis; Tertiary |
| Abstract | Living specimens of Distephanus speculum (Silicoflagellata) were collected in waters of ‹150 m depth in the Pacific Sector of the Southern Ocean (57°31.6'S, 150°02.9'E), South of Tasman Island, and a biometric study has been conducted. The skeleton of D. speculum has a simple morphology, which can be readily expressed quantitatively. Using a new methodology, repeated measurements were obtained and converted to numerical indices. The circumference of the basal rings was the most useful character for subdivision into groups, and using this parameter we recognized two populations in the 620 studied specimens: (1) 500 individuals were placed in Group A, with a basal ring circumference of 53 to 67 µm, and a difference in length of spine axes from 2 to 6 µm; and (2) 120 individuals were placed in Group B (basal ring circumference 80 to 105 µm, difference in length of spine axes 3 to 6 µm). The circumference of the basal ring in Group B is approximately 10 µm smaller than in Distephanus speculum giganteus [Bukry, D., 1979. Comments on opal phytoliths and stratigraphy of Neogene Silicoflagellates and Coccoliths at Deep Sea Drilling Project Site 397 off Northwest Africa. Initial report of the DSDP, Washington, 49:977-1009.], and Distephanus boliviensis [Bukry, D., 1976a. Silicoflagellate and coccolith stratigraphy, Norwegian-Greenland Sea. Initial Report of DSDP LEG 38. Initial report of the DSDP, Washington, 38:843-855.; Bukry, D., 1976b. Silicoflagellate and coccolith stratigraphy, southeastern Pacific Ocean, Deep Sea Drilling Project Leg 34. Initial report of the DSDP, Washington, 34:715-735]. |
| URL | http://hdl.handle.net/10.1016/j.marmicro.2009.06.003 |
| Publication Type | journal article |
| Record ID | 87513 |