Cryptic Female Choice in Crustaceans

Abstract

Cryptic female choice may be common among crustaceans , but few studies have thoroughly examined it in this diverse taxonomic group. Herein, we summarize current genetic evidence for multiple paternity and skewed offspring ratios in crustaceans, and document observations that could suggest cryptic female choice. Behaviors indicative of cryptic female choice have been reported from numerous crustacean taxa (e.g., crayfish , hermit crabs , isopods ), showcasing a diverse array of behavioral mechanisms such as failed copulations, spermatophore removal , selective sperm passage, chemical signaling , adjusting duration of receptivity, delayed copulation , or discriminative reproductive investment in favor of preferred males. We highlight a few case studies, in which a suite of different cryptic behaviors permits females to maintain control over fertilizations. The possibility of selective sperm–egg interactions is briefly discussed, and parallels to other aquatic invertebrates are drawn revealing similar cryptic choice mechanisms. The disparity of body forms and reproductive strategies found in crustaceans and the fact that they inhabit many different habitats with variable selective environments makes them an ideal model taxon for future studies on cryptic female choice

High prevalence of multiple paternity in the deep-sea shrimp Acanthephyra pelagica

“…Moreover, there are species like the snow crab, where females are highly polyandrous, yet they exhibit mostly single paternity (Sainte-Marie et al 2008). For a more extensive list of examples of multiple paternity in crustaceans see Dennenmoser and Thiel (2015). What factors or life history attributes influence the existence and prevalence of multiple mating?…”

“…Similar patterns have been found in other crustaceans: O. placidus (Walker et al 2002), C. ensifera (Yue and Chang 2010), P. clarkii , M. magister (Jensen and Bentzen 2012), D. primitivus (Jossart et al 2014) and R. typus (Bailie et al 2014). The causes for this skew vary and likely include pre-copulatory factors such as mating order , female choice, where the female mates several times with a preferred male (Thiel and Correa 2004), or different sperm contribution (ejaculate size) (Rondeau and Sainte-Marie 2001; Probability of detecting multiple mating in A. pelagica combining the four loci with the highest individual probability (Acpe20, Acpe26, Acpe51 and Acpe57) at different sample sizes, assuming 2 sires with a skew contribution to the offspring (90 and 10 %, respectively) Sato et al 2005;Pugh et al 2015;Moyano et al2015) or post-copulatory sperm competition or selection, which could happen by sperm digestion or by sperm sorting and differential use (Haase and Baur 1995;Thiel and Hinojosa 2003;Yue and Chang 2010;Dennenmoser and Thiel 2015). Within the caridean group, it has been observed that females of the species R. typus manipulate spermatophores and spawning time, in order to discriminate undesired males and favor preferred males (Thiel and Hinojosa 2003).…”

“…Although relatively few studies are available on mating systems within the crustacean class Malacostraca (Salmon 1983;Berg and Sandifer 1984;Bauer and Thiel 2011;Subramoniam 2013;Dennenmoser and Thiel 2015), it is known that Decapoda exhibit a variety of mating systems (Bilodeau et al 2005). Four mating systems have been described for caridean shrimps: monogamy, neighborhoods of dominance, pure searching and search and attend (Correa and Thiel 2003), and these mating systems have been described by Correa and Thiel (2003) in terms of the relation of each mating system and some specific traits in species.…”

“…The sexual systems of caridean shrimp are diverse, comprising gonochorism and protandric or simultaneous hermaphroditism. Multiple paternity is considered to be the norm within crustaceans (Dennenmoser and Thiel 2015) even though some species within the group present behaviors like post-copulatory guarding to prevent multiple mating (Salmon 1983). …”

From storage to delivery: sperm volume and number of spermatozoa inside storage organs and ejaculates in males ofTimogenes elegans(Scorpiones: Bothriuridae)

“…This cost is a result of spermatozoa being delivered together with accessory fluids (Dewsbury 1982). These fluids may be involved in many tasks, like maintaining spermatozoa, generating reluctance to mate with a subsequent male, (Chapman 2001;Arnqvist & Andrés 2006), or contributing to the formation of a genital plug (Kaufman et al 2008;Dennenmoser & Thiel 2015).…”