title: Potential costs of heterospecific sexual interactions in golden orbweb spiders (Nephila spp.).
abstract: Though not uncommon in other animals, heterospecific mating is rarely reported in arachnids. We investigated sexual interactions among four closely related and syntopical African golden orbweb spiders, Nephila inaurata, N. fenestrata, N. komaci, and N. senegalensis. In two South African localities, female webs were often inhabited by heterospecific males that sometimes outnumbered conspecifics. Species association of males with females was random in nature. In subsequent laboratory choice experiments, N. inaurata males chose heterospecific females in 30% of trials. We also observed natural mating interactions between N. inaurata males and N. komaci females, and between N. komaci males and N. inaurata females in laboratory experiments. While heterospecific mating in the laboratory never produced offspring, conspecific mating did. We discuss potential ecological and evolutionary consequences of heterospecific mating interactions in Nephila that may be particularly costly to the rarer species.
authors.affiliation: Evolutionary Zoology Laboratory, Biological Institute ZRC SAZU, Ljubljana, Slovenia.
authors.forename: Shakira G
authors.initials: SG
authors.lastname: Quiñones-Lebrón
authors.affiliation: Evolutionary Zoology Laboratory, Biological Institute ZRC SAZU, Ljubljana, Slovenia.
authors.forename: Simona
authors.initials: S
authors.lastname: Kralj-Fišer
authors.affiliation: Evolutionary Zoology Laboratory, Biological Institute ZRC SAZU, Ljubljana, Slovenia.
authors.forename: Matjaž
authors.initials: M
authors.lastname: Gregorič
authors.affiliation: Evolutionary Zoology Laboratory, Biological Institute ZRC SAZU, Ljubljana, Slovenia.
authors.forename: Tjaša
authors.initials: T
authors.lastname: Lokovšek
authors.affiliation: Evolutionary Zoology Laboratory, Biological Institute ZRC SAZU, Ljubljana, Slovenia.
authors.forename: Klemen
authors.initials: K
authors.lastname: Čandek
authors.affiliation: Department of Zoology &Entomology, University of the Free State, Bloemfontein, South Africa.
authors.forename: Charles R
authors.initials: CR
authors.lastname: Haddad
authors.affiliation: Evolutionary Zoology Laboratory, Biological Institute ZRC SAZU, Ljubljana, Slovenia.|Department of Entomology, National Museum of Natural History, Smithsonian Institution, Washington, D.C., USA.|Centre for Behavioural Ecology &Evolution (CBEE), College of Life Sciences, Hubei University, Wuhan, China.
authors.forename: Matjaž
authors.initials: M
authors.lastname: Kuntner
mesh_terms: D000818:Animals; D005260:Female; D008297:Male; D052586:Mating Preference, Animal; D012098:Reproduction; D013045:Species Specificity; D013112:Spiders / Q000502:physiology*