Embryonic Staging System for the Black Mastiff Bat,Molossus rufus(Molossidae), Correlated With Structure‐Function Relationships in the Adult

Abstract

An embryonic staging system for Molossus rufus (also widely known as Molossus ater) was devised using 17 reference specimens obtained during the postimplantation period of pregnancy from wild-caught, captivebred females. This was done in part by comparing the embryos to a developmental staging system that had been created for another, relatively unrelated bat, Carollia perspicillata (family Phyllostomidae). Particular attention was paid to the development of species-specific features, such as wing and ear morphology, and these are discussed in light of the adaptive significance of these structures in the adult. M. rufus can be maintained and bred in captivity and is relatively abundant in the wild. This embryonic staging system will facilitate further developmental studies of M. rufus, a model species for one of the largest and most successful chiropteran families, the Molossidae. Anat Rec, 292:155-168, 2009Rec, 292:155-168, . 2008 Wiley-Liss, Inc.Key words: bat; Chiroptera; Molossus rufus; Molossus ater; embryogenesis; embryonic staging systemThe bats (order Chiroptera) are one of the most successful mammalian groups. A recent compilation indicates that there are at least 1,116 species of bats, comprising a little more than 20% of all living mammalian species (Simmons, 2005;Wilson and Reeder, 2005), and they are exceedingly abundant mammals in absolute

Genetic Regulation of Mammalian Diversity

“…Perhaps not surprisingly, the embryonic staging systems for all bat species examined so far are very similar in terms of the relative timing, pattern, and initial appearance of major anatomical features (Giannini et al 2006; Tokita 2006; Hockman et al 2009; Nolte et al 2009). Species-specific differences in the shapes and sizes of some structures, such as craniofacial structures, limbs, and tail, appear after initial morphogenesis.…”

“…In particular, limb outgrowth and early morphogenesis appear to be highly conserved among all bat species examined. Differences in wing proportions corresponding to different flight behaviors of the various species appear during the last third of development (Giannini et al 2006; Tokita 2006; Hockman et al 2009; Nolte et al 2009). For example, digits II–V are spaced widely in the anteroposterior axis, with abundant wing membrane between them in C. perspicillata and Pipistrellus abramus (Cretekos et al 2005; Tokita 2006), whereas digits II–IV are relatively closer together, with less interdigital tissue in Molossus rufus forelimbs, reflecting the relatively broad wing shape in the former species and the narrower wing shape of M. rufus (Nolte et al 2009).…”

“…This has permitted the accumulation of substantial information on the timing of reproductive and developmental events in captive-maintained animals (Badwaik et al 1997; Rasweiler et al 2000; Cretekos et al 2005). Using embryos derived from timed matings from our laboratory colony, we generated a standardized embryo staging system for Carollia (Cretekos et al 2005), which has subsequently been modified for use with other species of bats (Giannini et al 2006; Tokita 2006; Hockman et al 2009; Nolte et al 2009). These various factors have enabled our studies on the genetic basis of limb diversity among mammals.…”

Endothelial cell hyperproliferation and stratification in uteroplacental blood vessels of the black mastiff bat, Molossus rufus

“…All of the bats used in this study were captured with mist nets on Trinidad, West Indies [5]. Most were maintained in captivity and many were bred with husbandry procedures described previously [6–9, 11].…”

“…As described below, this includes the hyperproliferation and stratification of maternal endothelial cells in uteroplacental vessels of the black mastiff bat, Molossus rufus . This species has also been widely referred to as Molossus ater [5]. …”