Polyplacophora species richness, composition and distribution of its community associated with the intertidal rocky substrate in the marine priority region No. 32 in Guerrero, Mexico

Abstract

The coast of Acapulco is located within the Marine Priority Region No. 32 (MPR No. 32) at the State of Guerrero, Mexico. The National Commission for the Knowledge and Use of Biodiversity has stated the lack of information on marine species that live there, among which are the Class Polyplacophora. This study aimed to: 1) determine species richness, 2) the community structure based on the representative families, 3) estimate the density, 4) locate species distribution, 5) determine their degree of occurrence (hierarchical position) within the community, 6) analyze the structure of length and width across the populations and 7) estimate the diversity index. The intertidal rocky substrate at seven beaches was sampled from 2009 to 2012. The sampling unit 1 m<sup>2</sup>, while the area sampled was 10 m<sup>2</sup>. It was analyzed 2.548 specimens of Polyplacophora, with 20 species identified. Tonicellidae and Ischnochitonidae were the Families better represented inspecies richness and Chitonidae in abundance. Lepidochitona flectens is a new record for the <i>Mexican Tropical Pacific</i> and <i>Stenoplax mariposa</i> for MPR. No. 32. The density was 25.48 specimens/m2. Eight dominant species were determined. Chiton albolineatus had the highest density. <i>Ischnochiton muscarius, Chaetopleura unilineata, Chiton albolineatus and Chiton articulatus</i> presented wide distribution. <i>Chiton articulatus</i> showed the largest size in length and width. H’ = 2.01 bits/ individual. Numerous dominant species were present with broad and regular distribution, probably due to Polyplacophora body design, which allows for better adaptation to the rigorous environmental conditions of the rocky intertidal

Diversidad de poliplacoforos tropicales del sur de la Provincia Panamena

“…De hecho, seis de las 11 especies encontradas son comunes en el Salvador y Costa Rica Jörger et al, 2008 Garza et al, 2012), y dos especies, Acanthopleura echinata y Chiton cumingsii, se distribuyen hasta el sur de Chile (Araya & Araya, 2015).…”

Mollusks of the Rocky Intertidal Zone at Three Sites in Oaxaca, Mexico

“…In the BIVALVIA Class, MYTILIDAE Family also was reported by [11] and [20] as the most abundant, which differs from that reported for Acapulco by [22] [24], who found the CHAMIDAE Family to be the most abundant. In the POLYPLACOPHORA Class CHITONIDAE Family was also reported to be the best represented in abundance by [18] [22] [24].…”

Diversity, Distribution and Composition of the Bivalvia Class on the Rocky Intertidal Zone of Marine Priority Region 32, Mexico

“…The stability of the substrate was classified as: 1) high: when the substrate remains virtually unchanged by the impact of waves, 2) middle: when the impact of the waves does not change the configuration of the substrate but there is rock movement, 3) low: when the site configuration is changed by the impact of waves, most of the The wave exposure was classified as: 1) high: when the wave hits the substrate in a free manner, usually the sites that have this type of waves are outside of the protection of barriers such as bays or hooks, 2) middle: when the impact of the wave on the substrate is hindered by barriers or smoothing, as can occur at sites that are in front of the entrance of bays or at a distance from a wall of hooks, it also happens in places where subtidal rocky substrate emerges or is shallow and reduces the direct impact of the waves to the substrate, 3) low: when the wave does not directly hit the substrate, since the sites are protected by different types of barriers [36].…”