Reproductive histology of Tomeurus gracilis Eigenmann, 1909 (Teleostei: Atherinomorpha: Poeciliidae) with comments on evolution of viviparity in atherinomorph fishes
Tomeurus gracilis is a species long considered pivotal in understanding the evolution of livebearing in atherinomorph fishes. Tomeurus gracilis is a zygoparous or embryoparous poeciliid: internal fertilization is followed by females laying fertilized eggs singly or retaining fertilized eggs until or...
Guardado en:
| Autores principales: | , , |
|---|---|
| Formato: | JOUR |
| Materias: | |
| Acceso en línea: | http://hdl.handle.net/20.500.12110/paper_03622525_v271_n11_p1399_Parenti |
| Aporte de: |
| id |
todo:paper_03622525_v271_n11_p1399_Parenti |
|---|---|
| record_format |
dspace |
| spelling |
todo:paper_03622525_v271_n11_p1399_Parenti2023-10-03T15:26:53Z Reproductive histology of Tomeurus gracilis Eigenmann, 1909 (Teleostei: Atherinomorpha: Poeciliidae) with comments on evolution of viviparity in atherinomorph fishes Parenti, L.R. Lonostro, F.L. Grier, H.J. Egg morphology Embryoparity/zygoparity Spermatozeugma Testis types Zona pellucida animal article cytology evolution female fish histology male oocyte ovary physiology reproduction spermatozoon testis ultrastructure viviparity Animals Biological Evolution Female Fishes Male Ovary Ovum Reproduction Spermatozoa Testis Viviparity, Nonmammalian Tomeurus gracilis is a species long considered pivotal in understanding the evolution of livebearing in atherinomorph fishes. Tomeurus gracilis is a zygoparous or embryoparous poeciliid: internal fertilization is followed by females laying fertilized eggs singly or retaining fertilized eggs until or near hatching. Tomeurus was hypothesized as the sister group of the viviparous poeciliids until it was proposed as a close relative of a derived viviparous poeciliid, Cnesterodon, hence nested among viviparous taxa rather than near the root of the tree. Here, we describe and compare reproductive morphological characters of the little-known Tomeurus with those of representative atherinomorphs. In Tomeurus and Cnesterodon, sperm are packaged in naked sperm bundles, or spermatozeugmata, in a configuration considered here diagnostic of viviparous poeciliids. Testes are single and free sperm are stored in the ovary in both taxa in contrast to oviparous atherinomorphs in which testes are paired and sperm are not packaged and not stored in the ovary. Efferent ducts in Cnesterodon testes and other viviparous poeciliids have a PAS-positive secretion demonstrating presence of a glycoprotein that inactivates sperm or prevents final sperm maturation. No PAS-positive staining secretion was observed in Tomeurus or oviparous atherinomorphs. Tomeurus shares apomorphic reproductive characters, such as sperm bundle and testis morphology and a gonopodium, with viviparous poeciliids and plesiomorphic characters, such as a thick zona pellucida with filaments, with oviparous taxa. We do not postulate loss or reversal of viviparity in Tomeurus, and we corroborate its phylogenetic position as sister to the viviparous poeciliids. © 2010 Wiley-Liss, Inc. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_03622525_v271_n11_p1399_Parenti |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Egg morphology Embryoparity/zygoparity Spermatozeugma Testis types Zona pellucida animal article cytology evolution female fish histology male oocyte ovary physiology reproduction spermatozoon testis ultrastructure viviparity Animals Biological Evolution Female Fishes Male Ovary Ovum Reproduction Spermatozoa Testis Viviparity, Nonmammalian |
| spellingShingle |
Egg morphology Embryoparity/zygoparity Spermatozeugma Testis types Zona pellucida animal article cytology evolution female fish histology male oocyte ovary physiology reproduction spermatozoon testis ultrastructure viviparity Animals Biological Evolution Female Fishes Male Ovary Ovum Reproduction Spermatozoa Testis Viviparity, Nonmammalian Parenti, L.R. Lonostro, F.L. Grier, H.J. Reproductive histology of Tomeurus gracilis Eigenmann, 1909 (Teleostei: Atherinomorpha: Poeciliidae) with comments on evolution of viviparity in atherinomorph fishes |
| topic_facet |
Egg morphology Embryoparity/zygoparity Spermatozeugma Testis types Zona pellucida animal article cytology evolution female fish histology male oocyte ovary physiology reproduction spermatozoon testis ultrastructure viviparity Animals Biological Evolution Female Fishes Male Ovary Ovum Reproduction Spermatozoa Testis Viviparity, Nonmammalian |
| description |
Tomeurus gracilis is a species long considered pivotal in understanding the evolution of livebearing in atherinomorph fishes. Tomeurus gracilis is a zygoparous or embryoparous poeciliid: internal fertilization is followed by females laying fertilized eggs singly or retaining fertilized eggs until or near hatching. Tomeurus was hypothesized as the sister group of the viviparous poeciliids until it was proposed as a close relative of a derived viviparous poeciliid, Cnesterodon, hence nested among viviparous taxa rather than near the root of the tree. Here, we describe and compare reproductive morphological characters of the little-known Tomeurus with those of representative atherinomorphs. In Tomeurus and Cnesterodon, sperm are packaged in naked sperm bundles, or spermatozeugmata, in a configuration considered here diagnostic of viviparous poeciliids. Testes are single and free sperm are stored in the ovary in both taxa in contrast to oviparous atherinomorphs in which testes are paired and sperm are not packaged and not stored in the ovary. Efferent ducts in Cnesterodon testes and other viviparous poeciliids have a PAS-positive secretion demonstrating presence of a glycoprotein that inactivates sperm or prevents final sperm maturation. No PAS-positive staining secretion was observed in Tomeurus or oviparous atherinomorphs. Tomeurus shares apomorphic reproductive characters, such as sperm bundle and testis morphology and a gonopodium, with viviparous poeciliids and plesiomorphic characters, such as a thick zona pellucida with filaments, with oviparous taxa. We do not postulate loss or reversal of viviparity in Tomeurus, and we corroborate its phylogenetic position as sister to the viviparous poeciliids. © 2010 Wiley-Liss, Inc. |
| format |
JOUR |
| author |
Parenti, L.R. Lonostro, F.L. Grier, H.J. |
| author_facet |
Parenti, L.R. Lonostro, F.L. Grier, H.J. |
| author_sort |
Parenti, L.R. |
| title |
Reproductive histology of Tomeurus gracilis Eigenmann, 1909 (Teleostei: Atherinomorpha: Poeciliidae) with comments on evolution of viviparity in atherinomorph fishes |
| title_short |
Reproductive histology of Tomeurus gracilis Eigenmann, 1909 (Teleostei: Atherinomorpha: Poeciliidae) with comments on evolution of viviparity in atherinomorph fishes |
| title_full |
Reproductive histology of Tomeurus gracilis Eigenmann, 1909 (Teleostei: Atherinomorpha: Poeciliidae) with comments on evolution of viviparity in atherinomorph fishes |
| title_fullStr |
Reproductive histology of Tomeurus gracilis Eigenmann, 1909 (Teleostei: Atherinomorpha: Poeciliidae) with comments on evolution of viviparity in atherinomorph fishes |
| title_full_unstemmed |
Reproductive histology of Tomeurus gracilis Eigenmann, 1909 (Teleostei: Atherinomorpha: Poeciliidae) with comments on evolution of viviparity in atherinomorph fishes |
| title_sort |
reproductive histology of tomeurus gracilis eigenmann, 1909 (teleostei: atherinomorpha: poeciliidae) with comments on evolution of viviparity in atherinomorph fishes |
| url |
http://hdl.handle.net/20.500.12110/paper_03622525_v271_n11_p1399_Parenti |
| work_keys_str_mv |
AT parentilr reproductivehistologyoftomeurusgraciliseigenmann1909teleosteiatherinomorphapoeciliidaewithcommentsonevolutionofviviparityinatherinomorphfishes AT lonostrofl reproductivehistologyoftomeurusgraciliseigenmann1909teleosteiatherinomorphapoeciliidaewithcommentsonevolutionofviviparityinatherinomorphfishes AT grierhj reproductivehistologyoftomeurusgraciliseigenmann1909teleosteiatherinomorphapoeciliidaewithcommentsonevolutionofviviparityinatherinomorphfishes |
| _version_ |
1807324416325976064 |