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We studied the structure and species composition of nine residual forest stands of Dacryodes excelsa (tabonuco), a dominant vegetation type in the moist and wet lower montane forests of the Caribbean. The stands were scattered over three different landscapes with different degrees of anthropogenic disturbance: forested, shade coffee, and tobacco. We compared our results with data from undisturbed stands inside a protected and forested landscape to see how the type of landscape that surrounded them affected the structure and species composition of the residual forest stands. In the process we sought conservation lessons that would help restore degraded tabonuco forests to original conditions. Tree density, basal area, and species density all increased with elevation. We found 98 tree species, including 50 of the 83 species that we identified as belonging to undisturbed tabonuco forests (including 13 of 18 endemic tree species), 41 tree species not reported for undisturbed tabonuco forests, eight primary forest species, and six introduced species. When ordered by species Importance Value by site, the stands in nine sites separated into three general groups corresponding to landscape type: (1) Heavily used for tobacco production. (2) Shade coffee, and (3) Forested. The importance of introduced species increased, and the abundance of tabonuco forest indicator species and endemic species decreased with increased anthropogenic disturbances. When restoring tabonuco forests, it is necessary to understand the landscape forces that influence the species composition of these forests. It appears that particular species combinations are natural outcomes of the level of anthropogenic activity in the landscape and reversing those tendencies might be impractical or too costly.

Callistochiton portobelensis Ferreira 1976 and Ischnochiton kaasi Ferreira, 1987 are reported for the fist time from the Colombian Caribbean. Both species were found in shallow water, under rocks, at Santa Marta in October 2009.

Los poliplacóforos asociados a los arrecifes de coral en la costa caribeña de Costa Rica han sido poco estudiados. El examen del cascajo de coral acumulado en el sublitoral somero, en cuatro estaciones de colección, localizadas en la Provincia de Limón reveló una diversidad de quitones mayor a la documentada. Anteriormente se habían registrado ocho especies para el Caribe costaricense: Ischnochiton erythronotus (C.B. Adams, 1845); Ischnoplax pectinata (Sowerby 1840); Stenoplax boogii (Haddon, 1886); S. purpurascens (C.B. Adams, 1845); Acanthopleura granulata (Gmelin, 1791); Chiton marmoratus Gmelin, 1791; C. tuberculatus Linnaeus, 1758; Acanthochitona rhodea (Pilsbry, 1893). Otras cinco se registran aquí por primera vez: Callistochiton portobelensis Ferreira 1976; Ischnochiton kaasi Ferreira 1987; I. pseudovirgatus Kaas 1972; Acanthochitona balesae Abbott 1954; Cryptoconchus floridanus (Dall 1889).Diversity and microstructure of quitons (Mollusca: Polyplacophora) from the Caribbean of Costa Rica. The polyplacophorans of the coral reef on the Caribbean coast of Costa Rica have been insufficiently studied. The examination of coral rubble accumulated in the shallow sublitoral waters on four collection stations in Provincia Limón revealed a higher diversity of chitons than was documented. From the country eight species were previously known: Ischnochiton erythronotus (C.B. Adams 1845); Ischnoplax pectinata (Sowerby 1840); Stenoplax boogii (Haddon 1886); S. purpurascens (C.B. Adams 1845); Acanthopleura granulate (Gmelin 1791); Chiton marmoratus Gmelin 1791; C. tuberculatus Linnaeus 1758 and Acanthochitona rhodea (Pilsbry 1893). This study added five more species that are reported here for the first time: Callistochiton portobelensis Ferreira 1976; Ischnochiton kaasi Ferreira 1987; I. pseudovirgatus Kaas 1972; Acanthochitona balesae Abbott 1954 and Cryptoconchus floridanus (Dall 1889). Rev. Biol. Trop. 59 (1): 129-136. Epub 2011 March 01.

A las ocho especies de poliplacóforos registradas en Bahía de la Paz, Baja California Sur, México, o cerca de ella, agregamos a Lepidochitona beanii, Chaetopleura lurida, Stenoplax limaciformis, S. mariposa, Lepidozona clathrata, L. serrata y Acanthochitona arragonites. El análisis de las comunidades estudiadas usando técnicas de ordenación sugiere que podría relacionarse la exposición al oleaje con la riqueza y la diversidad de especies. La comunidad recolectada en condiciones intermedias de exposición al oleaje presentó mayor número de especies y mayor diversidad de acuerdo con el índice de Shannon.Polyplacophoran communities (Mollusca: Polyplacophora) at Bahía de La Paz, Baja California Sur, México. Eight species of polyplacophorans have been reported from La Bahía de la Paz, Baja California Sur, Mexico. We add Lepidochitona beanii, Chaetopleura lurida, Stenoplax limaciformis, S. mariposa, Lepidozona clathrata, L. serrata and Acanthochitona arragonites, increasing the known number of species to 15. Ordination analysis of five chiton communities at the site suggests a correlation of wave exposure to species composition and diversity: communities with intermediate wave exposure have more species (richness) and higher diversity (Shannon’s index). Rev. Biol. Trop. 55 (1): 177-182. Epub 2007 March. 31.

En El Salvador se habían registrado los poliplacóforos Chaetopleura lurida (Sowerby, 1832); Ischnochiton guatemalensis (Thiele, 1910); Ceratozona angusta (Thiele, 1909); Chiton stokesii (Broderip, 1832) y Acantochitona exquisita (Pilsbry, 1893). Recolectamos quitones en aguas someras de El Salvador en julio del 2002, agragando a la lista a Lepidochitona beanii (Carpenter, 1857); Ischnochiton dispar (Sowerby, 1832); Stenoplax limaciformis (Sowerby, 1832); Callistochiton expressus (Carpenter, 1865); Acanthochitona arragonites (Carpenter, 1867); Acanthochitona ferreirai (Lyons, 1988) y Acanthochitona hirudiniformis (Sowerby, 1832). Ampliamos la distribución documentada de I. dispar hacia el norte y describimos brevemente una especie innominada de Lepidochitona.Chitons (Mollusca: Polyplacophora) from El Salvador, Central America. Collections of 11 species of shallow water Polyplacophora from El Salvador were made in July 2002. Previously only five species had been documented in El Salvador: Chaetopleura lurida (Sowerby, 1832); Ischnochiton guatemalensis (Thiele, 1910); Ceratozona angusta (Thiele, 1909); Chiton stokesii (Broderip, 1832) and Acantochitona exquisita (Pilsbry, 1893). Of these, I. guatemalensis and A. exquisita were not collected in this census. Seven other species are reported here for El Salvador for the first time: Lepidochitona beanii (Carpenter, 1857); Ischnochiton dispar (Sowerby, 1832); Stenoplax limaciformis (Sowerby, 1832); Callistochiton expressus (Carpenter, 1865); Acanthochitona arragonites (Carpenter, 1867); A. ferreirai (Lyons, 1988) and A. hirudiniformis (Sowerby, 1832). The known geographic distribution of I. dispar is extended to the north. An un-named species of Lepidochitona is briefly described. Rev. Biol. Trop. 55 (1): 171-176. Epub 2007 March. 31.