Review of the geographic distribution of Hoffmannola hansi (Gastropoda: Pulmonata) in the Mexican Pacific

Revisión del ámbito de distribución geográfica de Hoffmannola hansi (Gastropoda: Pulmonata) en el Pacífico mexicano

Omar Hernando Avila-Poveda¹*, Quetzalli Yasú Abadia-Chanona², Raúl Herrera-Fragoso³ and Benoît Dayrat⁴

¹ División de Estudios de Posgrado, Universidad del Mar, 70902 Puerto Ángel, Oaxaca, México. * oavila@colombia.com

³ Universidad La Salle-Nezahualcoyotl. Av. Bordo de Xochiaca, 57300 Nezahualcóyotl, Estado de México, México.

⁴ Department of Biology, Pennsylvania State University. University Park, 16802 PA, USA.

Recibido: 27 octubre 2012
Aceptado: 01 julio 2013

Abstract

Hoffmannola hansi (Mexican intertidal leather slug) is traditionally reported as an endemic species to the Gulf of California, Mexico. However, its presence in the southern Mexican Pacific has been mentioned in regional checklists and reports. Here we provide new records of H. hansi populations from at least 3 locations from Oaxaca, Mexico. The anatomical characteristics useful for H. hansi identification are described for both, living and preserved specimens. Specimen's reports from the Gulf of California to Oaxaca, Mexico, are mentioned, yielding a revised distribution throughout the Mexican Pacific. A map with the wider geographic distribution of H. hansi is also updated. Therefore, this species is not "endemic" to the Gulf of California, but is distributed throughout the Mexican Pacific. However its distribution is discontinuous with the possible existence of 2 cryptic species geographically separated by the Sinaloan gap: 1 in the North (Gulf of California) and 1 in the South. Additional work is needed to explore in more detail the complete geographical range of H. hansi populations on the entire Mexican Pacific Coast.

Key words: Mollusca, Onchidiidae, non-endemic, Oaxaca, Gulf of California, Tropical Eastern Pacific (TEP), geographical range, cryptic species.

Resumen

Hoffmannola hansi (babosa de cuero intermareal mexicana) es tradicionalmente registrada como una especie endémica del golfo de California, México. Sin embargo, su presencia en el sur del Pacífico mexicano ha sido mencionada en listas de control y en informes regionales. Ofrecemos nuevos registros de poblaciones de H. hansi de al menos 3 localidades de Oaxaca, México. Las características anatómicas que ayudan a identificar a H. Hansi se describen para ejemplares vivos y conservados. Se mencionan los ejemplares desde el golfo de California hasta Oaxaca, México, proporcionando una distribución ampliada a lo largo del Pacífico mexicano. Un mapa con la distribución geográfica de H. Hansi también se actualiza. Por lo tanto, esta especie no es endémica del golfo de California, sino que está bien distribuida en el Pacífico mexicano. Sin embargo, su distribución es discontinua, con la posible existencia de 2 especies crípticas geográficamente separadas por la brecha sinaloense: una en el Norte (golfo de California) y otra en el Sur. Sigue siendo necesario realizar trabajo adicional para explorar en mayor detalle la distribución geográfica completa de las poblaciones de H. hansi en toda la costa del Pacífico mexicano.

Palabras clave: Mollusca, Onchidiidae, no endémico, Oaxaca, golfo de California, Pacífico Oriental Tropical (POT), ámbito geográfico, especies crípticas.

Introduction

Currently, the Onchidiidae (Mollusca: Gastropoda: Pulmonata) is classified within the pulmonate gastropods (Holznagel et al., 2010; Wu et al., 2010; Dayrat et al., 2011a). However, its phylogenetic position has been heavily debated during the last 8 decades. Authors have considered them as opisthobranchs (Fretter, 1943; Boettger, 1954; Marcus, 1965; Marcus and Marcus, 1967; 1970), pulmonates (Bretnall, 1919; Baker, 1938; Baker, 1955; Ghiselin, 1965; Solem, 1978; Britton, 1984; Barker, 2001; Grande et al., 2004; Dayrat, 2009; Dayrat et al., 2011a,b), euthyneurans (Marcus and Burch, 1965; Selmi et al., 1988; Winnepenninckx et al., 1998; Dayrat and Tillier, 2000; 2002; 2003), or even as a separate Order Onchidiida (Starobogatov, 1976) and Silicodermatae (Labbé, 1934). Regardless, Onchidiidae remains a poorly-known taxon in many regards, especially in species diversity and distribution.

The most interesting aspect of the geographic range for Onchidiidae is that almost all the genera are exclusively found in tropical and subtropical areas from the Indo-West Pacific (Bretnall, 1919; Stringer, 1969; Wu et al., 2010) and the Mediterranean Sea (Barletta and Ghisotti, 1978), excepting 4 nominal Onchidella species and 2 nominal Hoffmannola species (i.e., H. hansi and H. lesliei) that are restricted to the tropical Eastern Pacific (Dayrat, 2009; Dayrat et al., 2011b). Onchidella has an extensive geographical range in all the tropical Eastern Pacific; while Hoffmannola hansi is restricted to the Northern Gulf of California and Hoffmannola lesliei to the Galapagos (e.g., Marcus and Marcus, 1967, 1970; Keen, 1971; Hendrickx et al., 2005; Dayrat, 2009; Dayrat et al., 2011a).

Hoffmannola hansi Marcus and Marcus, 1967 (for nomenclatural information, see, Dayrat et al., 2011b) has been known by its description as "endemic" commonly found in the rocky, intertidal communities of the Gulf of California, Mexico, across shores from Baja California Norte, Sonora, and Sinaloa (Marcus and Marcus, 1967, 1970; Keen, 1971; Hendrickx et al., 2005; Zamora-Silva and Naranjo-García, 2008; Dayrat, 2009; ASDM, 2011; Dayrat et al., 2011a). Nevertheless, various publications, reports, and regional checklists (none of which citing any deposited material) have mentioned H. hansi in other Mexican states and localities outside the Gulf of California and further south into the Mexican Pacific, such as, Jalisco (Esqueda-González, 1995; Esqueda et al., 2000), Jalisco, Colima and Michoacán (Holguín-Quiñones and González-Pedraza, 1994), Michoacán (Villaseñor-Gómez, 2005), Guerrero (Flores-Garza et al., 2005; 2007; Flores-Rodríguez et al., 2001, 2003, 2007, 2012; Flores-Rodríguez, 2004; Valdés-González et al., 2004) and Oaxaca (Rodríguez-Palacios et al., 1988; León-Herrera, 2000; 2001; Ramírez-González, 2008). Although they did not cite any actual specimens, those publications suggest that H. hansi may not be endemic to the Gulf of California.

The present study provides a review of the geographic distribution of H. hansi from available original literature (e.g., reports, grey literature, and regional checklists), several online databases of museum collections and specimens collected by our group Oaxaca, Mexico.

Material and methods

Specimens of different sizes of H. hansi were found while sampling for Chiton (Chiton) articulatus at Oaxaca (Avila-Poveda, 2013; Avila-Poveda and Abadia-Chanona, 2013). They were living next to 2 other species of mollusks (Chiton (Chiton) articulatus and/or Plicopurpura pansa) within crevices at high tide, or by themselves on the surface of rocks during low tide (Fig. 1). Several specimens of H. hansi were collected (n= 18, 14 ≤ TL ≤ 48 mm, total length, Fig. 2), in March, April, August, and October 2011 from 3 localities in Oaxaca, Mexico: 1) Puerto Angel (15°39' N, 96°29' W); 2) El Faro, Puerto Angel (15°39' N, 96°30' W), and 3) Conejos Bay, Huatulco (15°46' N, 96°04' W).

Three specimens (45 ± 3 mm TL, Fig. 3) were relaxed and allowed to extend for 1 h, with gradual additions of tap water to the seawater, until the salinity reached half the salinity of the seawater of the sampling site (i.e., 50:50 in volume: Avila-Poveda, 2013) and accelerating the relaxation process by adding few milliliters of 10% ethanol (after Lincoln and Sheals, 1979). Later, specimens were fixed in 10% neutral formalin-saline solution in seawater for 2 weeks and subsequently preserved in 70% ethanol (Avila-Poveda and Baqueiro-Cárdenas, 2009). Other specimens were preserved in 95% ethanol for future molecular work (Dayrat lab). The external and internal morphologies were studied under a dissecting microscope.

Specimens were (or shortly will be) deposited in museums in the region: 1) Laboratorio de Sistemática de Invertebrados Marinos (LABSIM), Universidad del Mar, Puerto Angel, Oaxaca, Mexico; 2) California Academy of Sciences (CAS), San Francisco, California, USA; 3) Santa Barbara Museum of Natural History (SBMNH), Santa Barbara County, California, USA; 4) Scripps Institution of Oceanography (SIO), San Diego, California, USA; 5) Arizona-Sonora Desert Museum (ASDM), Tucson, Arizona, USA; 6) Smithsonian National Museum of Natural History (NMNH), NW Washington, D.C., USA.

A checklist and a map of the geographic distribution of H. hansi were developed, based on records found for this species in scientific databases and web sites (e.g., BHL, BioStor, JSTOR, among many others), available original literature (e.g., reports and checklists), online databases of museum collections (e.g., ASDM, CAS, LABSIM, NMNH, SBMNH, SIO) and with the samples collected by our group Oaxaca, Mexico.

Results

The most important anatomical characters observed that help to identify the species are (for additional information, see: Dayrat et al., 2011b): 1) the total length of live specimens ranges from 14 mm to 48 mm (Fig. 3A) while preserved material is on average 25% shorter (e.g., the largest live specimen of 48 mm long measures only 33 mm once preserved; see, Fig. 3B); exceptionally, we observed specimens in the field that were longer than 48 mm, but in areas with difficult access; 2) the total width of the hyponotum (left and right side, H) relative to the width of the pedal sole (S) is around the third or fourth part (i.e., H <<< S) with H-S-H of 5-16/22-5 mm for live organisms, while these are 4-13/18-4 mm for the same preserved organisms; 3) there are generally about 14 marginal glands on the left and about 15 on the right; 4) the visceral cavity is divided in 2 by a septum (which actually is a characteristic of Hoffmannola).

During the sampling months (i.e., March, April, August, and October), early life stages of various species of intertidal mollusks such as Chiton (Chiton) albolineatus, Chiton (Chiton) articulatus, Echinolittorina aspera, Echinolittorina modesta, Plicopurpura pansa, Nerita scabricosta, and Hoffmannola hansi, among many others mollusks, were observed in large stocks that resembled a nursery.

A geographic distribution of H. hansi specimens was found available broadly over the Mexican pacific, and not just restricted to the Gulf of California (Table 1; Fig. 4).

Discussion

The checklist and map presented here show many more records of Hoffmannola hansi towards the Mexican south Pacific (records No. 13 to 36, total 24: Table 1; Fig. 4) than northern locations, where it has been termed as "endemic" to the Gulf of California ((records No. 3 to 12, total 10: Table 1; Fig. 4). Thus, H. hansi has been previously recorded in Jalisco (Esqueda et al., 2000), Jalisco, Colima and Michoacán (Holguín-Quiñones and González-Pedraza, 1994), Michoacán (Villaseñor-Gómez, 2005), Guerrero (Flores-Garza et al., 2005; 2007; Flores-Rodríguez et al., 2001, 2003, 2007, 2012; Flores-Rodríguez, 2004; Valdés-González et al., 2004) and Oaxaca (Rodríguez-Palacios et al., 1988; León-Herrera, 2000; 2001; Ramírez-González, 2008).

Based on information presented here, the localities of Puerto Angel, El Faro, and Conejos Bay of Huatulco, all in the state of Oaxaca, Mexico, should be incorporated into the species geographical distribution, as well as the states of Jalisco, Colima, Michoacán, and Guerrero, in Mexico, where H. hansi (Mexican intertidal leather slug) has been mentioned from the rocky intertidal.

In any case, H. hansi is not endemic to the Gulf of California, but is distributed throughout the Mexican Pacific, although its distribution is quite discontinuous. However, H. hansi requires rocky shores to live and large parts of the coast between the Gulf of California and southern Mexico are sandy beaches, especially the Sinaloan gap (Hastings, 2000). However, additional work is still needed to explore in more detail the complete geographical range of H. hansi populations on the entire Mexican Pacific Coast.

On the other hand, some errors were unveiled in the literature as well as online databases. Two museum records for H. hansi (NMNH 2011: USNM 771808 and USNM 710013) are likely to be incorrect, or at least questionable, since they are outside of the tropical Eastern Pacific and even in a different region of the Western Atlantic (Fig. 4). Feedback has been sent to NMNH Customer Service for its review (Avila-Poveda, pers. comm.).

Acknowledgments

This work was personally assured by Avila-Poveda OH with SNI-Conacyt stimulus (record No. 44175, from January to July 2012). Avila-Poveda OH gives special thanks for the family grant that covered his stay in the location during the course of this study. Thanks to Saúl Jaime Serrano-Guzmán for transporting the specimens to Benoît Dayrat at the School of Natural Sciences, University of California at Merced, California, USA. Thanks to Francisco Benitez-Villalobos for transporting and depositing some specimens in the NMNH (USNM 1155112). All rare references were downloaded via the Biodiversity Heritage Library (http://www.biodiversitylibrary.org/), Bioline International (http://www.bioline.org.br/), BioStor (http://biostor.org/), and Internet Archive (http://www.archive.org/).

Literature cited

ASDM (Arizona-Sonora Desert Museum). 2011. Macrofauna golfo invertebrate database http://www.desertmuseum.org/center/seaofcortez/searchdb.php; last access: 5.IV.2011.         [ Links ]

Avila-Poveda, O. H. 2013. Annual change in morphometry and in somatic and reproductive indices of Chiton articulatus adults (Mollusca: Polyplacophora) from Oaxaca, Mexican Pacific. American Malacological Bulletin 31:65-74.         [ Links ]

Avila-Poveda, O. H. and Q. Y. Abadia-Chanona. 2013. Emergence, development, and maturity of the gonad of two species of chitons "sea cockroach" (Mollusca: Polyplacophora) through the early life stages. PLoS ONE 8(8): e69785. doi:10.1371/journal.pone.0069785        [ Links ]

Avila-Poveda, O. H. and E. R. Baqueiro-Cárdenas. 2009. Reproductive cycle of Strombus gigas Linnaeus 1758 (Caenogastropoda: Strombidae) from Archipelago of San Andres, Providencia and Santa Catalina, Colombia. Invertebrate Reproduction and Development 53:1-12.         [ Links ]

Baker, H. B. 1955. Heterurethrous and Aulacopod. The Nautilus 68:109-112.         [ Links ]

Baker, H. B. 1938. Nomenclature of Onchidiidae. The Nautilus 51:85-88.         [ Links ]

Barker, G. M. 2001. Gastropods on land: phylogeny, diversity and adaptive morphology. In The biology of terrestrial molluscs, G. M. Barker (ed.). CABI Publishing, London. p. 1-146.         [ Links ]

Barletta, G. and F. Ghisotti. 1978. Primo rinvenimento di una forma Della famiglia Onchidiidae nel Golfo di Genova e in Tunisia (Gastropoda: Soleolifera). Bollettino di Zoologia 45:253-256. [Renamed as: Italian Journal of Zoology]         [ Links ].

Boettger, C. R. 1954. Die systematik der euthyneuren Schneken. Verhandlungen der Deutschen Zoologischen Geselschaft in Tübingen 18:253-280.         [ Links ]

Bretnall, B. W. 1919. Onchidiidae from Australia and the South-Western Pacific Islands. Records of the Australian Museum 12:303-328.         [ Links ]

Britton, K. M. 1984. The onchidiacea (Gastropoda, Pulmonata) of Hong Kong with a worldwide review of the genera. Journal of Molluscan Studies 50:179-191.         [ Links ]

CAS "California Academy of Sciences". 2011. Search the Collections Catalog. http://research.calacademy.org/redirect?url=http://researcharchive.calacademy.org/research/izg/iz_coll_db/index.asp; last access: 28.III.2011.         [ Links ]

Craig, M. T., P. A. Hastings, D. J. Pondella, D. R. Robertson and J. A. Rosales-Casián. 2006. Phylogeography of the flag cabrilla Epinephelus labriformis (Serranidae): implications for the biogeography of the Tropical Eastern Pacific and the early stages of speciation in a marine shore fish. Journal of Biogeography 33:969-979.         [ Links ]

Dayrat, B., M. Conrad, S. Balayan, T. R. White, C. Albrecht, R. Golding, S. R. Gomes, M. G. Harasewych and A. M. de-Frias-Martins. 2011a. Phylogenetic relationships and evolution of pulmonate gastropods (Mollusca): New insights from increased taxon sampling. Molecular Phylogenetics and Evolution 59:425-437        [ Links ]

Dayrat, B., S. Zimmermann and M. Raposa. 2011b. Taxonomic revision of the Onchidiidae (Mollusca: Gastropoda: Pulmonata) from the Tropical Eastern Pacific. Journal of Natural History 45:939-1003.         [ Links ]

Dayrat, B. 2009. Review of the current knowledge of the systematics of Onchidiidae (Mollusca: Gastropoda: Pulmonata) with a checklist of nominal species. Zootaxa 2068:1-26.         [ Links ]

Dayrat, B. and S. Tillier. 2003. Goals and limits of phylogenetics: the Euthyneuran gastropods. In Molecular systematics of mollusks, C. Lydeard and D. Lindberg (eds.). Smithsonian Institution Press, Washington D. C. p. 161-184.         [ Links ]

Dayrat, B. and S. Tillier. 2002. Evolutionary relationships of euthyneuran gastropods (Mollusca): a cladistic re-evaluation of morphological characters. Zoological Journal of the Linnean Society 135:403-470.         [ Links ]

Dayrat, B. and S. Tillier. 2000. Taxon sampling, character sampling and systematics: how gradist presuppositions created additional ganglia in gastropod euthyneuran taxa. Zoological Journal of the Linnean Society 129:403-418.         [ Links ]

Esqueda-González, M. C. 1995. Moluscos de la bahía de Cuastecomate, Jalisco, México. (Clases: Gastropoda y Bivalvia). B. Sc. Thesis. Facultad de Biología, Universidad de Guadalajara. Zapopán. 122 p        [ Links ]

Esqueda, M. C., E. Ríos-Jara, J. E. Michel-Morfín and V. Landa-Jaime. 2000. The vertical distribution and abundance of gastropods and bivalves from rocky beaches of Cuastecomate Bay, Jalisco, Mexico. Revista de Biología Tropical 48:765-775        [ Links ]

Flores-Garza, R., P. Flores-Rodríguez, S. García-Ibáñez and A. Valdés-González. 2007. Demografía del caracol Plicopurpura pansa (Neotaenioglossa: Muricidae) y constitución de la comunidad malacológica asociada en Guerrero, México. Revista de Biología Tropical 55:867-878.         [ Links ]

Flores-Garza, R., P. Flores-Rodríguez, S. García-Ibáñez, A. Valdés-González and D. Arana-Salvador. 2005. Estructura de la población de Plicopurpura patula pansa (gould, 1853) (Neotaenioglossa: Muricidae) y malacofauna asociada en el litoral rocoso del Estado de Guerrero. XVIII Congreso Nacional de Zoología, Monterrey, Nuevo León, Mexico, October 4-7, 2005. [Abstract 0272]         [ Links ].

Flores-Rodríguez, P. 2004. Estructura de la comunidad de moluscos del mesolitoral superior en playas de facie rocosa del estado de Guerrero, México. Ph.D. Thesis, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León. San Nicolás de los Garza. 207 p.         [ Links ]

Flores-Rodríguez, P., R. Flores-Garza, S. García-Ibáñez, A. Valdés-González, J. Violante-González, E. Santiago-Cortés, L. Galeana-Rebolledo and C. Torreblanca-Ramírez. 2012. Mollusk species richness on the rocky shores of the state of Guerrero, Mexico, as affected by rains and their geographical distribution. Natural Resources 3:248-260        [ Links ]

Flores-Rodríguez, P., R. Flores-Garza, S. García-Ibáñez and A. Valdés-González. 2007. Variación en la diversidad malacológica del mesolitoral rocoso en Playa Troncones, La Unión, Guerrero, México. Revista Mexicana de Biodiversidad 78:33S-40S.         [ Links ]

Flores-Rodríguez, P., R. Flores-Garza, S. García-Ibáñez and A. Valdés-González. 2003. Riqueza y diversidad de la malacofauna del mesolitoral rocoso de la Isla La Roqueta, Acapulco, Guerrero, México. Ciencia, Universidad Autónoma de Guerrero 11:5-14.         [ Links ]

Flores-Rodríguez, P., R. Flores-Garza, S. García-Ibáñez and A. Valdés-González. 2001. Malacofauna y estructura trófica del mesolitoral rocoso en la Costa Grande, Guerrero, México. VIII Reunión Nacional de Malacología y Conquiliología (Renamac), Ciudad Victoria, Tamaulipas, Mexico, September 25-28, 2001 [Abstract 32]         [ Links ].

Fretter, V. 1943. Studies in the functional morphology and embryology of Onchidella celtica (Forbes and Hanley) and their bearing on its relationships. Journal of the Marine Biological Association of the United Kingdom 25:685-720.         [ Links ]

Ghiselin, M. T. 1965. Reproductive function and the phylogeny of ophistobrach gastropods. Malacologia 3:327-378.         [ Links ]

Grande, C., J. Templado, J. L. Cervera and R. Zardoya. 2004. Phylogenetic relationships among Opisthobranchia (Mollusca: Gastropoda) based on mitochondrial cox 1, trnV, and rrnL genes. Molecular Phylogenetics and Evolution 33:378-388.         [ Links ]

Hastings, P. A. 2000. Biogeography of the Tropical Eastern Pacific: distribution and phylogeny of chaenopsid fishes. Zoological Journal of the Linnean Society 128:319-335.         [ Links ]

Hendrickx, M. E., R. C. Brusca and L. T. Findley. 2005. Listado y distribución de la macrofauna del golfo de California, México. Parte 1. Invertebrados. Arizona-Sonora Desert Museum, Tucson. 429 p.         [ Links ]

Holguín-Quiñones, O. E. and A. C. González-Pedraza. 1994. Moluscos de la franja costera de Michoacán, Colima y Jalisco, México. Instituto Politécnico Nacional, México, D. F. 150 p.         [ Links ]

Holznagel, W. E., D. J. Colgan and C. Lydeard. 2010. Pulmonate phylogeny based on 28S rRNA gene sequences: A framework for discussing habitat transitions and character transformation. Molecular Phylogenetics and Evolution 57:1017-1025        [ Links ]

Keen, A. M. 1971. Sea shell of Tropical West America. Marine mollusks from Baja California to Peru. Second Edition, Stanford University Press, California. 1063 p.         [ Links ]

Labbé, A. 1934. Les silicodermés (Labbé) du Museum d'Histoire Naturelle de Paris. Première partie: Classification, formes nouvelles ou peu connues. Annales de l'Institut Océanographique de Monaco 14:173-246.         [ Links ]

León-Herrera, M. G. 2001. Abundancia y diversidad de moluscos intermareales en seis playas rocosas del litoral Oaxaqueño. B. Sc. Thesis. Facultad de Biología Marina, Universidad del Mar. Puerto Ángel. 94 p.         [ Links ]

León-Herrera, M. G. 2000. Listado taxonómico de las especies de moluscos en la zona central del litoral Oaxaqueño. Ciencia y Mar 12:49-51.         [ Links ]

Lincoln, R. J. and J. G. Sheals. 1979. Invertebrate animals: collection and preservation. British Museum and Cambridge University Press. London. 150 p.         [ Links ]

Marcus, E. B. R. and E. Marcus. 1970. Some gastropods from Madagascar and West Mexico. Malacologia 10:181-223.         [ Links ]

Marcus, E. B. R. and E. Marcus. 1967. American Opisthobranch Mollusks. Studies in Tropical Oceanography 6:1-256.         [ Links ]

Marcus, E. 1965. Some Opisthobranchia from Micronesia. Malacologia 3:263-286.         [ Links ]

Marcus, E. and J. R. Burch. 1965. Marine Euthyneuran gastropoda from eniwetok atoll, Western Pacific. Malacologia 3:235-262.         [ Links ]

NMNH (Smithsonian National Museum of Natural History). 2011. Invertebrate zoology collections Search. http://collections.nmnh.si.edu/search/iz/; last access: 25.II.2011.         [ Links ]

Pitombo, F. B. and R. Burton. 2007. Systematics and biogeography of Tropical Eastern Pacific Chthamalus with descriptions of two new species (Cirripedia,Thoracica). Zootaxa 1574:1-30.         [ Links ]

Ramírez-González, A. 2008. Caracterización de Mollusca en la isla y en la bahía Cacaluta. In Diagnóstico de los recursos naturales de la bahía y micro-cuenca del río Cacaluta, Municipio de Santa María Huatulco, Oaxaca, J. M. Domínguez-Licona (ed.). Universidad del Mar, Huatulco. p. 211-242.         [ Links ]

Rodríguez-Palacios, C. A., L. M. Mitchell-Arana, G. Sandoval-Díaz, P. Gómez and G. Green. 1988. Los moluscos de las bahías de Huatulco y Puerto Ángel, Oaxaca. Distribución, diversidad y abundancia. Universidad y Ciencia 5:85-94.         [ Links ]

Selmi, M. G., F. Giusti and G. Manganelli. 1988. The fine structure of the mature spermatozoon of Onchidella celtica (Cuvier) (Mollusca: Gastropoda) and its phylogenetic implications. Journal of Ultrastructure and Molecular Structure Research 99:107-123.         [ Links ]

Solem, A. 1978. Classification of the land Mollusca. In Pulmonates: systematics, evolution and ecology, Vol. 2A, V. Fretter and J. Peake (eds.). Academic Press, New York. p. 49-97.         [ Links ]

Starobogatov, Y. I. 1976. Composition and taxonomic position of marine pulmonate mollusks. Soviet Journal of Marine Biology 4:206-212.         [ Links ]

Stringer, B. L. 1969. The species of New Zealand Onchidiidae (mollusca, gastropoda) and their distribution. New Zealand Journal of Marine and Freshwater Research 3:29-45        [ Links ]

Valdés-González, A., P. Flores-Rodríguez, R. Flores-Garza and S. García-Ibáñez. 2004. Molluscan communities of the rocky intertidal zone at two sites with different wave action on isla La Roqueta, Acapulco, Guerrero, Mexico. Journal of Shellfish Research 23:875-880.         [ Links ]

Villaseñor-Gómez, L. E. 2005. La biodiversidad en Michoacán: estudio de estado. Comisión Nacional para el Conocimiento y Uso de la Biodiversidad, Secretaría de Urbanismo y Medio Ambiente, Universidad Michoacana de San Nicolás de Hidalgo, Mexico D. F. 760 p.         [ Links ]

Wares, J. P. 2001. Patterns of speciation inferred from mitochondrial DNA in North American Chthamalus (Cirripedia: Balanomorpha: Chthamaloidea). Molecular Phylogenetics and Evolution 18:104-116.         [ Links ]

Wares, J. P., M. S. Pankey, F. Pitombo, L. G. Daglio and Y. Achituv. 2009. A "shallow phylogeny" of shallow barnacles (Chthamalus). Plos One 4: e5567. doi:10.1371/journal.pone.0005567        [ Links ]

Winnepenninckx, B., G. Steiner, T. Backeljau and R. De-Wachter. 1998. Details of gastropod phylogeny inferred from 18S rRNA sequences. Molecular Phylogenetics and Evolution 9:55-63.         [ Links ]

Wu, W. J., B. Shen, C. Chen, H. D. Shen, L. L. Wei, L. Wang and K. Li. 2010. Preliminary classification and phylogenetic relationship among onchidiidae in China inferred from 18S rRNA partial sequence. Zoological Research 31:381-386.         [ Links ]

Zamora-Silva, A. and E. Naranjo-García. 2008. Los opistobranquios de la Colección Nacional de Moluscos. Revista Mexicana de Biodiversidad 79:333-342.         [ Links ]