The biology of Vaejovis littoralis Williams, an intertidal scorpion from Baja California, Mexico

Abstract

Vaejovis littoralis Williams is an intertidal scorpion inhabiting chiefly the drift zone in the high intertidal of beaches in Baja California, Mexico. Density within the drift zone averages approximately 2–4/m2 (island sites) to 12/m2 (mainland sites). Populations are aggregated into patches. Primarily, juveniles exhibit diurnal activity. Nocturnally active juveniles tend to be spatially segregated from nocturnally active adults within the drift zone. Diet of V. littoralis includes the isopod Ligia, V. littoralis, spiders, pseudoscorpions, centipedes and beetles. Prey size is not a function of predator size. Centruroides exilicauda, V. littoralis and Ligia were observed as predators on V. littoralis. The adult sex ratio is skewed toward females (1 male : 2.1 females). Adult females are usually larger than adult males. Litter size ranges from 1–8. Limited data suggest that offspring size and litter size increase with maternal size. Vaejovis littoralis exhibits cryptic coloration, small size and lithophilic tarsal claws, all of which favour intertidal existence. Although V. littoralis is able to withstand up to 12 hours of submergence, it does not survive submergence significantly better than a comparable desert species. Field data suggest that V. littoralis does not exhibit an endogenous tidal rhythm.

A primer on the history of food web ecology: Fundamental contributions of fourteen researchers

“…Much of Polis' food web research focused on impacts that marine subsidies had on terrestrial food webs, with coastal deserts of Baja California as a model Polis, 1999, 2004;Due and Polis, 1985;Polis et al, 1997;Polis andHurd, 1995, 1996;Rose and Polis, 1998). These systems were supported by various marine-derived subsidies, including algal wrack, dead aquatic animals, and seabird guano, the effects of which varied by subsidy type.…”

The genus Akrav Levy, 2007 (Scorpiones: Akravidae) revisited

“…& Fet, 2003b); neither appear to be closely related to Akrav. The time of divergence of Akrav and its New is the upper age of the shrinking Tethys, and such Ecology of the Gulf of California (Due & Polis, 1985), wh 2 World relatives from their common ancestor cannot be confidently estimated. Our only fossil-based dating of chactoid families comes from a single Cretaceous genus Araripescorpius (Crato Formation, Brazil), which is classified in modern Chactidae (Menon, 2007).…”

Keystone Species on New Zealand Offshore Islands: Ecological Relationships of Seabirds, Rats, Reptiles and Invertebrates on Cook Strait Islands

“…At other locations, nrch as the high tempoature/low rainfall islnnds of Baja California" terresilial plam biornass is very low Hurd 1995, 1996). Nutrie1f iryut into t5g foodweb comes dmost solety from a marine source (Due andPolis 19t5, polis ad Hurd 1995, 1996) and nnim"ls in Baja California are highly euiched in t3C. A narine efrest is clear in the tissrrcs of Baja Califunda animels (Arderson and polis l99g).…”