Evidence of Xysticus ulmi (Hahn) (Araneae: Thomisidae) Predation on Adult Cassida viridis Linnaeus (Coleoptera: Chrysomelidae)

Posted by
  Evidence of Xysticus ulmi (Hahn) (Araneae: Thomisidae) Predation on Adult Cassida viridis Linnaeus (Coleoptera: Chrysomelidae) Tortoise beetles (Chrysomelidae: Cassidinae) have several morphological and behavioral antipredator traits. For example, the soft larvae accumulate their feces and exuviae from previous instars to create a so-called “fecal shield” (Engel 1936; Kosior 1975), which functions as a defense against many predator guilds (Eisner and Eisner 2000; Eisner et al. 1968; Vencl et al. 1999, 2005; Vencl and Srygley 2013). Adults are characterized by their explanate and well-sclerotized pronota and elytra, which cover all soft parts of the body, thereby forming a tortoise-shaped shield (Buzzi 1988; Engel 1936; Jolivet 1997; Jolivet and Verma 2002; Selman 1988; Windsor et al. 1992) (Fig. 1A). Furthermore, the adults are known for their ability to grip firmly to surfaces with both tarsal claws and pads, which renders them difficult to capture (Buzzi 1988; Engel 1936; Joliv...

Two new and unusual species of Tibelloides Mello-Leitão, 1939 (Araneae: Philodromidae)

Posted by

 


Two new and unusual species of Tibelloides Mello-Leitão, 1939 (Araneae: Philodromidae)

Abstract

Tibelloides Mello-Leitão, 1939 currently included four species of Neotropical grass-dwelling spiders. Herein, we describe and illustrate Tibelloides castelo sp. nov. with few records from Brazil (Minas Gerais, Piauí, Rio de Janeiro), and Tibelloides juatuba sp. nov. , with records from Brazil (Minas Gerais, Pará, Paraná, Rondônia) and Paraguay (San Pedro). These two new species differ from the previously described ones by having body and legs conspicuously longer and thinner, male pedipalp without retrolateral marginal conductor, and female genitalia with compound copulatory ducts tubular and elongated.

Prado, A. W. do, Pantoja, P. & Baptista, R. L. C. (2024). Two new and unusual species of Tibelloides Mello-Leitão, 1939 (Araneae: Philodromidae). Zootaxa 5497(4): 559-576. doi:10.11646/zootaxa.5497.4.6