Oviparous Hermaphroditic Fish with Internal Self-Fertilization

Abstract

Adults of Rivulus marmoratus (Cyprinodontidae) contained eggs when dissected or laid eggs when kept alive. They invariably oviposited solo, emitting eggs in various developmental stages. Both juvenescent and senescent fish have functional ovotestes. Progeny (F3) were obtained via a selfed great grandparent, grandparent, and parent, the last two in isolation ab ovo.

Gonadal morphology in the self-fertilizing mangrove killifish, Kryptolebias marmoratus

“…The self-fertilization of this species had confirmed only by the observation of oviposited fertilized eggs from fish kept individually (Harrington, 1961). Genetic studies have also confirmed that all reproduction of hermaphrodites in this species is by internal self-fertilization (Harrington and Kallman, 1968).…”

“…The mangrove killifish, Kryptolebias marmoratus (family Rivulidae), is the only known self-fertilizing hermaphroditic vertebrate (Harrington, 1961;Warner, 1978), and it is of interest for its unique reproductive biology (Harrington, 1968(Harrington, , 1975. Costa (2004) reexamined the taxonomy of the Rivulidae and recognized Rivulus marmoratus as a synonym of K. marmoratus.…”

Long-term retention of self-fertilization in a fish clade

“…Exceptions are thus of evolutionary interest. Simultaneous hermaphroditism and self-fertilization in K. marmoratus were discovered in the 1960s (3). Later, researchers used molecular markers to confirm self-fertilization in this species (8) and to derive the first quantitative estimates of selfing and outcrossing rates (9)(10)(11)(12).…”

“…H ermaphroditism is not uncommon in fishes (1,2), but self-fertilization is rare; among all vertebrate animals, only the mangrove rivulus (Kryptolebias marmoratus) offers a wellconfirmed case (3,4). Even among plants and invertebrates, where monoecy and hermaphroditism are widespread, outcrossing often remains the primary reproductive mode (5).…”

Embryonic development of the self‐fertilizing mangrove killifish Kryptolebias marmoratus

“…The mangrove killifish Kryptolebias marmoratus, previously known as Rivulus marmoratus (Poey, 1880), has been the only known simultaneous hermaphroditic vertebrate able to self-fertilize (Harrington, 1961). However, Tatarenkov et al (2009) recently demonstrated that a related nominal species, Kryptolebias ocellatus, is also capable of self-fertilization.…”