Potential costs of heterospecific sexual interactions in golden orbweb spiders (Nephila spp.)

• Published in: Scientific reports Vol. 6; no. 1; p. 36908
• Main Authors: Quiñones-Lebrón, Shakira G, Kralj-Fišer, Simona, Gregorič, Matjaž, Lokovšek, Tjaša, Čandek, Klemen, Haddad, Charles R, Kuntner, Matjaž
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 15.11.2016
• Subjects: Animal behavior; Animals; Conspecifics; Female; Females; Laboratories; Male; Males; Mating; Mating Preference, Animal; Nephila; Nephila fenestrata; Nephila inaurata; Nephila komaci; Nephila senegalensis; Offspring; Reproduction; Species Specificity; Spiders; Spiders - physiology; Webs
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep36908

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.