Notes on the neotropical genus Macrinus ( Araneae : Sparassidae )

Macrinus Simon, 1887 can be diagnosed by the twisted tegulum with a distal retrolateral laminar projection and the fulcrum with a prolateral serrated projection on the male palp and by the copulatory ducts with an anterior, fused hyaline part and a median long and sclerotized part ending at a slightly rounded spermathecae in the female epigynum. The genus currently includes three species: Macrinus succineus Simon, 1887 and M. jaegeri Rheims, 2007, from Brazil, and M. pollexensis (Schenkel, 1953) from Venezuela. In this paper I describe two new species: Macrinus bambuco sp. nov. and Macrinus calypso sp. nov. The first is based on a male from Lomalinda, Colombia, and is distinguished from the remaining Macrinus by the presence of a retrolateral triangular projection on the tegulum of the male palp. The second is based on a male from Charlotteville, Tobago, and is distinguished from the remaining species by a small retrolateral process at the base of the RTA. In addition, Olios mohavensis Fox, 1937, from the Mojave Desert in California, USA, is transferred to Macrinus. The species can be distinguished from the remaining species of the genus by a median anterior constriction on the anterior margin of the median septum of the female epigynum. It’s distribution range is extended to southwestern North America, in the Nearctic region. No Macrinus species is known to occur in Central America.

Macrinus Simon, 1887 was recently revised and includes at present only three species restricted to South America (RHEIMS 2007, PLATNICK 2010).Macrinus succineus Simon, 1887 was originally described from São Paulo de Olivença, state of Amazonas, Brazil and its distribution range covers western South America, from northern Guyana to southeastern Brazil.Macrinus pollexensis (Schenkel, 1953) was described from El Pozon, Fálcon, Venezuela and its distribution range covers mostly eastern South America, from Venezuela to southeastern Brazil.The third and recently described Macrinus jaegeri Rheims, 2007 has a more central distribution, with records from the states of Pará and Mato Grosso, Brazil (RHEIMS 2007).
While examining material from North, Central and northern South America, deposited in some of the largest American museums (American Museum of Natural History, National Museum of Natural History in the Smithsonian Institution, Museum of Comparative Zoology and California Academy of Sciences), I came across the type specimen of Olios mohavensis, described by FOX (1937) from the Mojave Desert in California.Despite the fact that no other Macrinus specimens were found amongst the Central and North American material and no species is known to occur outside South America, the study of the female genitalia showed that this species is clearly congeneric with M. succineus and should thus be transferred to that genus.The species is herein redescribed and illustrated in detail.Further investigation and sampling carried out in the type locality might shed some light as to how this species landed in the middle of the Desert and why there are no Macrinus recorded from Central America.
In addition, two new species are described, one from Lomalinda, Colombia, and one from Charlotteville, Tobago, increasing the genus composition to six species and extending it's distribution range to southwestern North America.

MATERIAL AND METHODS
The specimens dealt with in this paper are deposited in the National Museum of Natural History, Smithsonian Institution (USNM, curator: J. Coddington) and California Academy of Sciences (CAS, curator: C.E. Griswold).
Morphological observations and illustrations were made using a Leica MZ12 stereomicroscope with a camera lucida.Notes on the neotropical genus Macrinus ZOOLOGIA 27 (3): 440-444, June, 2010 Measurements were taken with a micrometric ocular and are given in millimeters.Female epigynum was dissected and submerged in clove oil to study internal structures.
Distribution.Known only from the type locality.
Macrinus bambuco sp.nov.Diagnosis.The males of M. bambuco sp.nov.are distinguished from those of the remaining species of the genus by the RTA strongly bent ventrally (Fig. 5) and by the presence of a retrolateral triangular projection on the tegulum of palp (Fig. 4, TP).
Distribution.Only known from the type locality.
Etymology.The specific name is a noun in apposition that refers to Colombian folk music.The rhythm is sometimes said to be the unofficial music of Colombia and has a widespread popularity throughout Latin America.Diagnosis.Males of M. calypso sp.nov.are distinguished from those of the remaining species of the genus by the small process at the retrolateral base of the RTA and by the retrolateral keel on the tegulum of the male palp (Figs 6 and 7).
Etymology.The specific name is a noun in apposition that refers to the folk music from Tobago.