Abstract: The distribution of all 56 abalone species is documented based on specimen records. The three models for the origin of the family (Pacific Rim, Indo-Pacific, Tethys) are evaluated. The area cladogram, which treats the distribution of the individual species as characters and the areas as taxa, is in general agreement with an unrooted phylogenetic tree of the taxa for which the geographic occurrence is superimposed. The basal node of the area cladogram is a fairly large polytomy uniting rather distant provinces such as the north Pacific, Australia, and Africa. A similar pattern emerges from the taxon cladogram. Accordingly, a very general Indo-Pacific origin emerges, best in agreement with the Indo-Pacific model for the origin of the family. The apparent discrepancy with the fossil record is discussed. Although the earliest fossils from the Upper Creatceous have been found in the Caribbean and in California, a major hiatus of on the order of 200 million years can easily account for the discrepancy between the earliest fosssils and the biogeographical reconstruction, as well as for the large basal polytomy in the biogeographical analysis. All species are illustrated, including some distinct juvenile forms, and 30 photographs of live animals. riassunto: Distribuzione e Biogeografìa delle Haliotidae (Gastropoda: Vetigastropoda) recenti. Le Haliotidae comprendono 56 specie recenti descritte, distribuite su scala mondiale, nelle aree temperate e tropicali di entrambi gli emisferi. La distribuzione di tutte le 56 specie è qui illustrata da mappe digitalizzate, sulla base dell'esame oggettivo di esemplari e dell'analisi critica dei dati di letteratura. Sono quindi esaminati i tre modelli proposti per l'origine della famiglia: "Pacific Rim", Indo-Pacifico e Tetisiano. Il cladogramma di area, che tratta le distribuzioni delle singole specie come caratteri e le aree come OTUs, è in accordo generale con un albero filogenetico delle specie (derivato dall'analisi cladistica di dati molecolari ed allozimici) su cui vengano sovrimposte le distribuzioni geografiche. Il nodo basale del cladogramma di area è una politomia piuttosto ampia che riunisce provincie relativamente distanti come il Nord-Pacifico, l'Australia e l'Africa. Un quadro simile emerge dal cladogramma dei taxa. Sulla base dell'analisi di tali cladogrammi emerge un'origine generale Indo-Pacifica del gruppo, che sembrerebbe supportare il modello Indo-Pacifico di origine delle Haliotidae. Vi è un'apparente discrepanza tra questi dati e la loro susseguente interpretazione da una parte, e il record fossile dall'altra. I fossili più antichi noti provengono infatti dal Cretaceo Superiore dei Caraibi e della California. Ciononostante viene discusso come uno iato dell'ordine di 200 milioni di anni possa facilmente spiegare la discrepanza tra i fossili più antichi e la ricostruzione biogeografica più plausibile; si darebbe così anche ragione dell'ampia politomia basale nelle analisi cladistiche. Tutte le specie sono illustrate, con alcune distinte forme giovanili caratterizzate e 30 fotografie di animali viventi. Daniel L. Geiger, Molecular Systematic! Lab, Naturai History Museum of Los Angeles University, Los Angeles, CA 90007, USA; e-mail dgeiger@nmh.org INTRODUCTION Abalone are a family of marine gastropods consisting of 56 currently described species of world-wide distribution in tropical and temperate waters of both hemispheres. During revision work on this family I have recently evaluated all Recent taxa, 200 at the species level and 17 at the genus level (Geiger, 1998a). Some other taxonomic matters have been dealt with elsewhere (Geiger 1998b, 1999; Geiger & Stewart, 1998, Stewart & Geiger, 1999). Knowledge of the distribution of most species is sketchy, particularly due to the absence of specimen based accounts. Most indications in the literature may be termed intuitive (e.g., Ubaldi, 1993, 1995) with limited exceptions (Geiger, 1996, 1999; Simone, 1998; Stewart & Geiger, 1999). In this second, larger treatment of the family Haliotidae, I concentrate on the distributional pattern of all Recent species, including a biogeographical analysis. To date, studies on the biogeography ol the family are marked by their anecdotal nature. Three hypotheses (Fig. 1) for the origin have been proposed and have been discussed by Geiger & Groves (1999) in a review of fossil abalone. Model 1 (Fig. 1A): Pacific Rim. An arc spanning from Japan to northeastern Australia has been identified by Talmadge (1963) as a likely cradle of the family. From this nuclear distribution abalone then dispersed in a star shaped pattern to the northwestern and then northeastern Pacific, to Australia and the Indian Ocean. The basis of this model was never made explicit. Model 2 (Fig. IB): Indo-Pacific. The highest present day diversity of the family is found in the Indo-Malayan area. Although it is well appreciated that the correlation of high present day diversity with origin of the group in question is highly problematic, it provides one possible center of radiation for the family, and was discussed by LlNDBERG (1992) and BRIGGS