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Little is known about microhabitat use by Caribbean parrotfishes soon after settlement from the plankton. We monitored the abundance and distribution of recently settled Sparisoma spp. (likely mostly S. viride with some S. aurofrenatum) on 6 × 6 m quadrats (n = 9) on the fringing reef front in Barbados (West Indies) every 15 d for 6 mo. Each quadrat was divided into 1 m2 cells to examine associations between substrate composition and recruit (Stegastes diencaeus and threespot damselfish S. planifrons. Whereas Sparisoma recruits overlapped with longfins and to a lesser extent with threespots, small juveniles overlapped only with threespots. Some of the microhabitat associations with recruits and small juveniles at the cell scale were also found across quadrats. We suggest that the reef front is an important habitat for recently settled Sparisoma in Barbados, where they rely on being cryptic and solitary within turf algae gardens defended by damselfishes to minimize predation. After some growth, they perform a microhabitat shift, perhaps due to increased damselfish aggression. Thus, the early post-settlement dynamics of Caribbean Sparisoma might be strongly influenced by substrate modification by algal-gardening damselfishes.

Damselfish of the genus Stegastes inhabit territories and cultivate algal gardens on branching corals of the genus Acropora, aggressively protecting their territories from other fish and preventing predation upon corals within the territory. This behaviour has important ecological impacts and could also be useful in reducing predation on outplanted corals during reef restoration efforts. However, the degree of protection from predators may depend on the ability of Stegastes spp. to recolonise outplanted or newly established coral colonies. Protection of bleaching-resilient massive corals within territories may be of particular importance due to the role of these corals in maintaining coral cover following bleaching events. This study examined whether the presence of Stegastes spp. reduces predation on the massive bleaching-resilient coral Porites lutea in the Mauritian lagoon, and whether Stegastes spp. readily colonise outplanted branching coral fragments and provide adjacent massive corals with indirect protection from predation. Predation levels on wild-occurring and outplanted P. lutea within and outside Stegastes spp. territories were measured. In addition, Acropora muricata branches were outplanted adjacent to wild P. lutea colonies outside Stegastes spp. territories, and recolonisation of these outplants by Stegastes spp. and the impacts of recolonisation on predation were monitored. Both wild and outplanted P. lutea colonies within Stegastes spp. territories sustained less predation damage compared to colonies outside territories. Stegastes spp. recolonized outplanted A. muricata colonies within six months of outplanting, and in doing so returned predation protection to adjacent P. lutea colonies. The ability of Stegastes spp. to colonise outplanted corals and provide indirect protection to adjacent massive bleaching-resilient corals may inform coral outplanting efforts in systems where Stegastes spp. are common. Encouraging Stegastes spp. recolonisation may help to reduce predation damage to corals within territories and potentially improve the success of rehabilitation efforts.

Parasites are an integral part of coral reef ecosystems due to their influences on population dynamics, biodiversity, community structure, and food web connectivity. The Phylum Apicomplexa contains ubiquitous animal associates including the causative agents of globally important human diseases such as malaria and cryptosporidiosis. Despite their ubiquity, little is known about the biology, ecology, or distribution of these microorganisms in natural animal populations. In the US Virgin Islands, the dusky damselfish (Stegastes adustus) had a high but variable incidence of a Haemohormidium-like blood apicomplexan among 30 sites sampled. Microscopic analyses of blood smears allowed us to group these fish as infected, having low intensity infections, or uninfected. Regression analyses detected no significant differences in the condition indices (expressed as length–mass ratio). However, infection was clearly associated with potentially extremely high leukocyte counts among infected S. adustus that were not seen in uninfected fish. These results suggested the potential for some impact on the host. Linear mixed effects models indicated that S. adustus population density and meridional flow velocity were the main predictors of apicomplexan prevalence, with presence of other Stegastes species, population distance from watershed, zonal flow velocity, the complexity of the surrounding habitat, and season not showing any significant relationship with fish infection.

La última valoración sobre la extensión, estado y cobertura viva (%) de las formaciones de Acropora palmata (29) y A. cervicornis (12) en el Parque Nacional Natural Tayrona fue realizada en 2001 y publicada en 2004. Estas mismas formaciones, incluyendo una adicional en isla Aguja, fueron evaluadas de nuevo entre 2016 y 2018 teniendo en cuenta las mismas variables, y adicionalmente el registro de condición de las colonias. Para A. palmata se encontraron 24 formaciones con una reducción en área de 28,9 %. La cobertura promedio aumentó cerca de 2,0 %, y se observó una amplia distribución de frecuencia de tallas y una proporción importante de colonias con territorios de peces damisela (Stegastes). El área de las formaciones de A. cervicornis se redujo 99,3 % y solo se encontró una formación en Nenguange, aunque se registran dos nuevas y pequeñas en Cinto y otra en Chengue. La cobertura promedio fue de 8,0 %, en su mayoría constituida por colonias de talla pequeña y principalmente afectadas por blanqueamiento, macroalgas, enfermedades y depredadores. Claramente el estatus de las dos especies es diferente por lo que requieren esfuerzos diferentes para su manejo y conservación. Las formaciones de A. palmata han persistido, pero es necesario realizar estudios continuos que permitan detectar cambios temporales, con evaluaciones de aspectos ecológicos como las afectaciones por los peces damisela. El estado de A. cerviconis es crítico, por lo que demanda acciones urgentes de restauración y otras medidas de manejo para mitigar la tendencia a su desaparición en el área.

Algal turfs are currently the most abundant benthic component on most coral reefs. Their wide distribution, functional role and positive responseto factors that stress corals confirm their importance in the functioning of reef ecosystem. It has been shown that species composition, structuraldevelopment and sediment retention influence their capacity to kill and displace adjacent live coral tissue. In this study in two reefs of the Tayrona National Natural Park (Colombian Caribbean), the variation in structure of turfs growing on and in direct interaction with massive live corals was determined,and its structural complexity was related with its sediment retention capacity. For that, the taxonomical composition was determined, and canopy height, cover and density of filaments and algal biomass were quantified for turfs growing on live colonies of four species of corals. The results showed that there are important structural differences between reefs and substratum type. In Granate reef (10-16 m), turfs form discontinuous carpets over crustose algae, and are constituted by articulated calcareous and little corticated algae, and juveniles of frondose algae, mostly of the genus Dictyota. During coastal upwelling, this genus grows profusely forming transient dense algal beds that later detach. In contrast, in Nenguange reef (4-6 m), turfs are perennial, form low, thick and dense carpets, with few crustose algae, and are dominated by filamentous and small corticated algae. It´s suggested that the presence of territories ofdamselfishes (Stegastes spp.) aid controlling the structural complexity of the turfs, and that vegetative propagation is the most frequent growth mechanism. In addition, it was found that the most morphologically complex turfs can retain greater amounts of sediments (silt-clay). This particulate material supports them; they can advance laterally and smother adjacent live coral tissue. This investigation provides the first quantitative data on the structure and amount of retained sediments by algal turfs growing on Colombian reef corals.

Damselfishes are known keystone species of reef environments, however large-scale distribution patterns are poorly studied in the southwestern Atlantic. We evaluated main drivers of distribution of three conspicuous damselfishes, along tropical and subtropical coastal systems, in Brazil. Abundances were assessed against wave exposure, depth (within 1–7 m in tropical and 1–11 m in subtropical reefs) and benthic cover. Despite differences between systems, exposure and depth consistently explained damselfishes distribution. Stegastes fuscus, the larger damselfish species of the genus in the southwestern Atlantic, was dominant in both systems, inhabiting preferably shallow and sheltered reefs. Conversely, Stegastes variabilis occupied shallow habitats with higher exposure. Stegastes pictus was absent from tropical reefs sampled, inhabiting depths >7 m, in subtropical reefs. Species were weakly associated with benthic features, which poorly predicted changes in abundances. Regardless, S. fuscus showed association with articulated calcareous algae, and S. variabilis juveniles associated with erect macroalgae. Despite occurring in very distinctive reef systems, Brazilian damsels habitat requirements are consistent in both tropical and subtropical reefs. While highly persistent species, long term monitoring will inform us how they respond to pervasive global changes and human impacts along Brazilian reefs. Resumo Os peixes donzela são espécies-chave em ambientes recifais, contudo seus padrões de distribuição em grande escala são pouco conhecidos no sudoeste do Atlântico. Avaliamos os principais descritores de distribuição para três espécies comuns em sistemas recifais tropicais e costões rochosos subtropicais costeiros no Brasil, em resposta a diferentes regimes de exposição a ondas, profundidade e cobertura bentônica. Apesar das grandes diferenças entre estes sistemas, a exposição das ondas e a profundidade consistentemente explicaram sua distribuição. Stegastes fuscus é numericamente dominante, sendo a maior espécie do gênero no Atlântico sudoeste, dominando recifes rasos e menos hidrodinâmicos, enquanto S. variabilis foi mais abundante em habitats com maior hidrodinamismo. Stegastes pictus foi ausente nos recifes rasos tropicais amostrados e, nos recifes rochosos subtropicais, foi mais abundante em profundidades acima de 7 m. Características do substrato influenciaram pouco a densidade, porem S. fuscus apresentou associação a algas calcárias articuladas, enquanto juvenis de S. variabilis se associaram a macroalgas eretas. Peixes donzelas são generalistas e persistentes, ocorrendo em ambientes distintos, e mesmo assim, regulados de forma especifica e consistente ao longo da costa. O monitoramento a longo prazo nos informará como elas responderão às constantes mudanças globais e impactos antrópicos nos recifes brasileiros.

Understanding the processes that shape biodiversity is essential for effective environmental management. Across the world’s coral reefs, algal farming damselfish (Stegastes sp.) modify the surrounding benthic community through their creation of algae “farms”. Using a long-term monitoring dataset (2005–2019) from Moorea Island, French Polynesia, we investigated whether the density of dusky damselfish (Stegastes nigricans) is associated with benthic habitat composition, the density of predators and/or competitors, and whether the survey area was inside or outside of a Marine Protected Area (MPA). We found no evidence that benthic cover or number of competitors were associated with dusky damselfish densities, both inside and outside MPAs. In contrast, fluctuations in dusky damselfish densities were negatively associated with the density of predators (e.g. Serranidae, Muraenidae and Scorpaenidae) in the preceding year in non-MPA areas, and both within and outside of MPAs when predator densities were high (2005–2010). These results suggest that healthy predator populations may be important for regulating the abundances of keystone species, such as algal farming damselfish, especially when predator densities are high.

Stegastes rectifraenum (Gill, 1862). Cortez Damselfish or Cortez Gregory. To 16 cm (6.3 in) TL (John Snow, pers. comm. to M.L.). Isla San Mart��n (30��28���N, 116��07���W) (M.L., unpubl. data), northern Baja California to Pucusana, Peru (Chirichigno and V��lez 1998), including Gulf of California (Thomson et al. 1979) and Islas Revillagigedo.Depth: intertidal to 27 m (90 ft) (min.: Thomson and Lehner 1976; max.: Personal communication: Scripps Institution of Oceanography Fish Collection, La Jolla, California)., Published as part of Love, Milton S., Bizzarro, Joseph J., Cornthwaite, Maria, Frable, Benjamin W. & Maslenikov, Katherine P., 2021, Checklist of marine and estuarine fishes from the Alaska-Yukon Border, Beaufort Sea, to Cabo San Lucas, Mexico, pp. 1-285 in Zootaxa 5053 (1) on page 175, DOI: 10.11646/zootaxa.5053.1.1, http://zenodo.org/record/5578008, {"references":["Chirichigno, F. N. & Velez D, J. (1998) Clave para identificaticar los peces marinos del Peru (segunda edicion, revisada y actualizada). Instituto de Mar de Peru Publicacion Especial.","Thomson, D. A., Findley, L. T. & Kerstitch, A. N. (1979) Reef Fishes of the Sea of Cortez. John Wiley and Sons, New York.","Thomson, D. A. & Lehner, C. E. (1976.) Resilience of a rocky intertidal fish community in a physically unstable environment. Journal of Experimental Marine Biology and Ecology, 22, 1 - 29."]}

Stegastes acapulcoensis (Fowler, 1944). Acapulco Damselfish or Acapulco Major. To 18.8 cm (7.4 in) TL (Urbiola-Rangel and Chassin-Noria 2019). Punta Peque��a (26��14���N, 112��31���W), southern Baja California (Personal communication: Scripps Institution of Oceanography Fish Collection, La Jolla, California) to lower Gulf of California (Schneider and Krupp in Fischer et al. 1995) and to Islas Lobos de Afuera, Peru (Chirichigno and V��lez 1998), including southern tip of Baja California (Schneider and Krupp in Fischer et al. 1995) and Islas Gal��pagos (Grove and Lavenberg 1997). Depth: intertidal to 16 m (53 ft) (min.: Castellanos-Galindo et al. 2014; max.: Schneider and Krupp in Fischer et al. 1995)., Published as part of Love, Milton S., Bizzarro, Joseph J., Cornthwaite, Maria, Frable, Benjamin W. & Maslenikov, Katherine P., 2021, Checklist of marine and estuarine fishes from the Alaska-Yukon Border, Beaufort Sea, to Cabo San Lucas, Mexico, pp. 1-285 in Zootaxa 5053 (1) on page 175, DOI: 10.11646/zootaxa.5053.1.1, http://zenodo.org/record/5578008, {"references":["Urbiola-Rangel, E. & Chassin-Noria, O. (2019) Mating and reproductive success associated with male body size in Stegastes acapulcoenesis (Teleostei: Pomacentridae). Environmental Biology of Fishes, 102, 1473 - 1483. https: // doi. org / 10.1007 / s 10641 - 019 - 00925 - z","Fischer, W., Krupp, F., Schneider, W., Sommer, C., Carpenter, K. E. & Niem, V. H. (1995) Guia FAO para la identificacion para los fines de la pesca. Pacifico centro-oriental. Volume II, Vertebrados, Parte 1. Volume III, Vertebrados, Parte 2. FAO, Rome.","Chirichigno, F. N. & Velez D, J. (1998) Clave para identificaticar los peces marinos del Peru (segunda edicion, revisada y actualizada). Instituto de Mar de Peru Publicacion Especial.","Grove, J. S. & Lavenberg, R. J. (1997) The Fishes of the Galapagos Islands. Stanford University Press, Stanford.","Castellanos-Galindo, G. A., Giraldo, A. & Zapata, F. A. (2014) Tidepool fish assemblages of Gorgona Island, Colombian Pacific coast: a local and regional comparison). Revista de Biologia Tropical, 62 (Supplement 1), 373 - 390. https: // doi. org / 10.15517 / rbt. v 62 i 0.16362"]}

Stegastes flavilatus (Gill, 1862). Beaubrummel, Beaubrummel Gregory, or Beaubrummel Major. To 16 cm (6.3 in) TL (John Snow, pers. comm. to M.L.). Isla de Cedros (Ram��rez-Valdez et al. 2015) and (mainland) Rocas Chester (27��53���N, 115��47���W) (M.L., unpubl. data), central Baja California to Pucusana, Peru (Chirichigno and V��lez 1998), including Gulf of California (Galv��n-Maga��a et al. 1996), Islas Gal��pagos (Grove and Lavenberg 1997), and other offshore islands (Robertson and Allen 2002). Depth: intertidal to 38 m (125 ft) (min.: Ruiz-Campos et al. 2010b; max.: Thomson et al. 2000)., Published as part of Love, Milton S., Bizzarro, Joseph J., Cornthwaite, Maria, Frable, Benjamin W. & Maslenikov, Katherine P., 2021, Checklist of marine and estuarine fishes from the Alaska-Yukon Border, Beaufort Sea, to Cabo San Lucas, Mexico, pp. 1-285 in Zootaxa 5053 (1) on page 175, DOI: 10.11646/zootaxa.5053.1.1, http://zenodo.org/record/5578008, {"references":["Ramirez-Valdez, A., Aburto-Oropeza, O., Palacios-Salgado, D. S., Reyes-Bonilla, H., Dominguez Guerro, I., Hinojosa Arango, G., Correa S., F., Villasenor-Derbez, J. C., Cota-Nieto, J. J. & Hernadez-Velasco, A. (2015) The nearshore fishes of the Cedros Archipelago (north-eastern Pacific) and their biogeographic affinities. CalCOFI Reports, 56, 143 - 167.","Chirichigno, F. N. & Velez D, J. (1998) Clave para identificaticar los peces marinos del Peru (segunda edicion, revisada y actualizada). Instituto de Mar de Peru Publicacion Especial.","Galvan-Magana, F., Abitia-Cardenas, L. A., Rodriguez-Romero, J., Perez-Espana, H. & Chavez-Ramos, H. (1996) Systematic list of the fishes from Cerralvo Island, Baja California Sur, Mexico. Ciencias Marinas, 22, 295 - 311.","Grove, J. S. & Lavenberg, R. J. (1997) The Fishes of the Galapagos Islands. Stanford University Press, Stanford.","Robertson, D. R. & Allen, G. R. (2002) Shorefishes of the tropical eastern Pacific: an information system. CD-ROM. Smithsonian Tropical Research Institute, Balboa, Panama.","Ruiz-Campos, G., Gonzalez-Guzman, S., Ramirez-Valdez, A., Gonzalez-Acosta, A. F., Castro-Aguirre, J. L. & de la Cruz-Aguero, J. (2010 b) Composition, density and biogeographic affinities of the rocky intertidal fishes on the western coast of the Baja California Peninsula, Mexico. CalCOFI Reports, 51, 210 - 220."]}

Stegastes leucorus (Gilbert, 1892). Whitetail Damselfish or Whitetail Major. To 17 cm (6.7 in) TL (Allen and Robertson 1994). Santa Catalina and San Clemente Islands, southern California and Islas Coronados, northern Baja California (Love et al. 2016a); Isla Guadalupe (Allen and Robertson 1994) and Islas San Benito (Personal communication: Scripps Institution of Oceanography Fish Collection, La Jolla, California); Bah��a Magdalena, southern Baja California (Hern��ndez-Velasco et al. 2016), and south-western Baja California; Mazatl��n, Mexico (Thomson et al. 1979) and offshore islands (Robertson and Allen 2015). Depth: 0���18 m (60 ft) (min.: Robertson and Allen 2002; max.: Personal communication: Scripps Institution of Oceanography Fish Collection, La Jolla, California)., Published as part of Love, Milton S., Bizzarro, Joseph J., Cornthwaite, Maria, Frable, Benjamin W. & Maslenikov, Katherine P., 2021, Checklist of marine and estuarine fishes from the Alaska-Yukon Border, Beaufort Sea, to Cabo San Lucas, Mexico, pp. 1-285 in Zootaxa 5053 (1) on page 175, DOI: 10.11646/zootaxa.5053.1.1, http://zenodo.org/record/5578008, {"references":["Allen, G. R. & Robertson, D. R. (1994) Fishes of the Tropical Eastern Pacific. University of Hawaii Press, Honolulu.","Hernandez-Velasco, A., Fernandez-Rivera-Melo, F. J., Melo-Merino, S. M. & Villasenor-Derbez, J. C. (2016) Occurrence of Holacanthus clarionensis (Pomacanthidae), Stegastes leucorus, and Stegastes acapulcoensis (Pomacentridae) at Magdalena Bay, B. C. S., Mexico. Marine Biodiversity Records, 9, 49. https: // doi. org / 10.1186 / s 41200 - 016 - 0062 - 1","Thomson, D. A., Findley, L. T. & Kerstitch, A. N. (1979) Reef Fishes of the Sea of Cortez. John Wiley and Sons, New York.","Robertson, D. R. and Allen, G. R. (2015) Shorefishes of the Tropical Eastern Pacific: an Information System. Version 2.0 (2008). Smithsonian Tropical Research Institute, Balboa. http: // biogeodb. stri. si. edu / sftep / en / pages","Robertson, D. R. & Allen, G. R. (2002) Shorefishes of the tropical eastern Pacific: an information system. CD-ROM. Smithsonian Tropical Research Institute, Balboa, Panama."]}

Stegastes. —The 40 circumtropical species traditionally classified in this genus (farmerfishes or gregories) are characterized as aggressive, benthic damselfishes (Allen, 1975a; Allen and Emery, 1985; Allen and Smith, 1992; Smith-Vaniz et al., 1999) that engage in territorial behavior and algal farming (Vine, 1974; Belk, 1975; Allen and Robertson, 1994; Ceccarelli et al., 2001; Hata and Kato, 2004, 2006; Frédérich et al., 2013; Hata and Ceccarelli, 2016; Pratchett et al., 2016). The genus has long posed a challenge to systematists (Bleeker, 1877; Longley and Hildebrand, 1941; Rivas, 1960; Emery and Burgess, 1974; Greenfield and Woods, 1974; Emery and Allen, 1980; Allen and Emery, 1985; Smith-Vaniz et al., 1999). Stegastes is not monophyletic as currently constituted (Fig. 1), which corroborates other phylogenetic studies that have shown the same (e.g., Cooper et al., 2009; Cowman and Bellwood, 2011; Hofmann et al., 2012; Litsios et al., 2012a, 2012b; Frédérich et al., 2013; Rabosky et al., 2013, 2018; DiBattista et al., 2016; Mirande, 2016; Gaboriau et al., 2018; Delrieu-Trottin et al., 2019). Instead, the species fall into two disjunct clades, one of which is nested within Plectroglyphidodon and the other includes the type species, S. imbricatus. The latter group, Stegastes sensu stricto, would have been rendered non-monophyletic by the presence of ‘‘ Plectroglyphidodon ’’ lacrymatus, if not for its reclassification as Stegastes (see above). The two groups can be generally distinguished by the number of dorsal-fin spines: XII in Stegastes sensu stricto vs. XIII or XIV in ‘‘ Stegastes ’’ associated with Plectroglyphidodon. Allen (1975a: 42), who used the number of dorsal spines in his key for Stegastes (as Eupomacentrus), suggested the genus could be divided into two subgenera based on this difference. However, although instructive, this character is not strictly diagnostic. Of the species sampled in this study, there are at least three exceptions: S. pelicieri (XIV, with Stegastes sensu stricto), S. altus, and S. aureus (XII, with ‘‘ Stegastes,’’ S. altus occasionally has XIII; Allen, 1991). The presence of XII spines in Stegastes sensu stricto mostly fits the original conception of Stegastes and Eupomacentrus, a widely used junior synonym, which were both characterized by XII dorsal spines (Jenyns, 1840; Bleeker, 1877; Emery and Allen, 1980). The results of this analysis imply that later additions to this genus, namely Indo-Pacific species with XIII spines (Allen, 1975a; Emery and Allen, 1980), are not part of Stegastes sensu stricto. There are three junior synonyms of Stegastes: Brachypomacentrus, Eupomacentrus, and Omopomacentrus. Atlhough simultaneous, Eupomacentrus Bleeker, 1877 has priority over Brachypomacentrus Bleeker, 1877 (ICZN, 1999: Art. 24.1) because Eupomacentrus was proposed at a higher rank (Bleeker, 1877). The type species of all three genera appear to be members of Stegastes sensu stricto. We recovered S. albifasciatus, the type of Brachypomacentrus, in the same clade as S. imbricatus. Stegastes lividus, the type of Eupomacentrus, presents an interesting situation. Randall (2004) discovered that the widespread species universally accepted as S. lividus (e.g., Bleeker, 1877; Fowler and Bean, 1928; Montalban, 1928; Whitley, 1929; de Beaufort, 1940; Aoyagi, 1941; Smith, 1960; Woods and Schultz, 1960; Allen, 1975a, 1991, 1997; Masuda et al., 1975, 1984; Allen and Randall, 1981; Allen and Emery, 1985; Randall et al., 1997; Myers, 1999; Jang-Liaw et al., 2002; Lieske and Myers, 2002) should be called S. punctatus because the S. lividus of Forster in Bloch and Schneider (1801) is endemic to the Marquesas Islands, where it had been recognized by Randall (2001) as Stegastes robertsoni. The taxonomic species that Bleeker (1877) fixed as the type of Eupomacentrus was actually S. punctatus. In cases where the type species was misidentified but correctly fixed, either species involved in the misidentification may be subsequently designated as the type (ICZN, 1999: Arts. 67.9, 70.3). However, Randall (2004) did not take any taxonomic action, presumably because Eupomacentrus was not in use. In our phylogeny, S. punctatus is in the same clade as S. imbricatus. Even though we were unable to examine S. lividus, based on the number of the dorsal spines (XII) and the phylogenetic position of S. albifasciatus, which Randall (2001, 2005) proposed as its closest relative, it is likely that S. lividus is also part of Stegastes sensu stricto. Finally, S. acapulcoensis, the type species of Omopomacentrus, is an eastern Pacific species with XII dorsal spines found in the same clade as S. imbricatus. Based on the phylogenetic position of S. acapulcoensis, Omopomacentrus is a synonym of Stegastes, not Pomacentrus, as stated by Kottelat (2013). This is in agreement with numerous authors who have regarded acapulcoensis as a species of Stegastes (e.g., Allen and Woods, 1980; Allen, 1991; Allen and Robertson, 1994; Grove and Lavenberg, 1997; Thomson et al., 2000; Robertson and Allen, 2015). Stegastes sensu stricto is resolved as a monophyletic group, with the inclusion of S. lacrymatus. Within it, there is 100% bootstrap support for a clade comprising the Atlantic and eastern Pacific species, which all have XII dorsal spines. The phylogeny suggests that Stegastes sensu stricto diversified following a colonization of Neotropical waters. In their review of eastern Pacific Stegastes, Allen and Woods (1980) recognized that those species were closely related to the Atlantic ones. We recovered a sister-group relationship between S. acapulcoensis and S. rectifraenum, which was posited by Thomson et al. (2000) based on similarities in juvenile color patterns. The phylogeny supports a S. partitus – S. pictus relationship (100% bootstrap) first identified by Emery and Allen (1980), on the basis of both species possessing one fewer row of cheek scales (3) than other Stegastes (4). In their analysis of Atlantic Stegastes, Souza et al. (2016) also recovered a S. partitus – S. pictus clade. Our topology shares other similarities with theirs: a clade composed of S. adustus, S. beebei, S. diencaeus, S. flavilatus, S. variabilis, and S. xanthurus (treated as a population of S. variabilis therein); another clade of S. arcifrons, S. fuscus, S. planifrons, S. rectifraenum, and S. rocasensis; a third clade of S. albifasciatus, S. limbatus, S. nigricans, and S. punctatus. They demonstrated a divergence between the Brazilian and Caribbean populations of S. variabilis, which corroborates the restriction of S. variabilis to Brazil and recognition of S. xanthurus as the widespread species that occurs in the Caribbean (Robertson and Van Tassell, 2012; Smith-Vaniz and Jelks, 2014; Robertson et al., 2016a). Stegastes sensu stricto includes most of the Indo-West Pacific species that possess XII dorsal-fin spines plus S. pelicieri, which has XIV spines. In their revision of the Indo-Pacific Stegastes sensu lato, Allen and Emery (1985) noted that, unlike many other widespread genera, much of its diversity falls outside of the region. They differentiated four species (S. albifasciatus, S. limbatus, S. lividus [¼ S. punctatus], and S. nigricans) from the remainder of Stegastes. They linked S. albifasciatus and S. nigricans together as part of a species complex, but separated S. limbatus and S. lividus [¼ S. punctatus] each into their own lineages. In our phylogeny, all four species form a monophyletic group (100% bootstrap) that is the sister taxon of the eastern Pacific/Atlantic Stegastes. Hubert et al. (2017: fig. A1, tables S3, S4) reported spatial structure within S. nigricans, with discrete lineages representing the Indian and Pacific Oceans. Even though they described it as geographic paraphyly (their ‘‘pattern II.2’’), their figure (Hubert et al., 2017: fig. A1) shows geographic monophyly (their ‘‘pattern II.1’’). If those populations are recognized as cryptic diversity, there is an available name in the synonymy of S. nigricans that could apply to the western Indian Ocean population, Pomacentrus scolopseus. The Indo-Pacific ‘‘ Stegastes ’’ also form a monophyletic group (100% bootstrap support; Fig. 1), but their placement renders Plectroglyphidodon paraphyletic. Species in this ‘‘ Stegastes ’’ are confined to the Indo-Pacific and typically have XIII or more dorsal spines, except for S. altus and S. aureus, which usually have XII dorsal spines (rarely XIII in altus; Allen and Emery, 1985). The group includes the species circumscribed as the ‘‘ fasciolatus complex’’ by Allen and Emery (1985): S. aureus, S. emeryi, S. fasciolatus, S. gascoynei, and S. insularis. Our phylogeny found all of them together in a clade, along with S. luteobrunneus and S. marginatus, which were considered synonyms of S. fasciolatus by Allen and Emery (1985), as well as S. altus. This fasciolatus complex plus S. altus is well supported (100% bootstrap). Allen and Emery (1985) considered S. altus part of a different species complex that also comprised S. apicalis and S. obreptus, with the latter two species hypothesized to be most closely related. Although the topology did resolve S. apicalis and S. obreptus as sister species (100% bootstrap), our results placed S. altus inside the fasciolatus clade. The S. apicalis þ S. obreptus pair is sister to the fasciolatus complex. All of these species form a monophyletic group (100% bootstrap) within Plectroglyphidodon, which is also composed entirely of Indo-Pacific taxa. In addition to rendering Plectroglyphidodon paraphyletic, this clade of ‘‘ Stegastes ’’ lacks an available name. Cowman and Bellwood (2011: figs. 2b, S6) called a group with similar composition ‘‘ Stegastes et al. IP.’’ Cooper and Santini (2016: fig. 1) called it ‘‘ Stegastes II / Plectroglyphidodon II / Parma II’’ and suggested that several of these species (e.g., S. altus, S. apicalis, S. fasciolatus, S. obreptus) would eventually need to be classified as Plectroglyphidodon, but they did not formally make the taxonomic change. The diagnoses for both genera largely overlap (Allen, 1975a; Allen and Emery, 1985), with two conspicuous differences: margin of preopercle smooth in Plectroglyphidodon vs. serrated in adult Stegastes; margin of suborbital smooth in Plectroglyphidodon vs. variable (serrated, crenulated, or smooth) in Stegastes. We hereby assign the following species to Plectroglyphidodon: altus, apicalis, aureus, emeryi, fasciolatus, gascoynei, insularis, luteobrunneus, marginatus, and obreptus. Plectroglyphidodon and Stegastes are both masculine, so no changes for gender agreement are necessary. Based on geographic variations in color, Allen and Emery (1985: 16, pl. I–II) recognized three distinct populations within the widespread Stegastes fasciolatus [¼ Plectroglyphidodon fasciolatus]: Hawaiian Islands; Indo-West Pacific Ocean (type locality: Lord Howe Island); western Indian Ocean and Cocos-Keeling Islands. Citing unpublished sequence data from D. R. Roberston, Randall (2005, 2007) stated that each population should be recognized as a separate species. Randall (2005) indicated that S. fasciolatus sensu stricto should be restricted to the population in the eastern Indian Ocean (Christmas Island and western Australia), Oceania (excluding Hawaii), and the western Pacific Ocean. Randall (2007) resurrected Stegastes marginatus for the Hawaiian population, removing it from the synonymy of S. fasciolatus. Following Randall (2005), Fricke et al. (2009) resurrected Stegastes luteobrunneus for the western Indian Ocean population (including Cocos-Keeling). The sequences for Plectroglyphidodon luteobrunneus used in this analysis (JF435094, JF457578, JF458207) come from a sample currently identified as Pomacentrus agassizii (BOLD record: IPCOM438-10; BOLD sample ID: REU0983). Moreover, all currently published sequences labeled as ‘‘ Pomacentrus agassizii ’’ (JF435094– JF435098; JF457578–JF457582; JF458207–JF458211; JQ350239–JQ350240; MF409473) appear to be Plectroglyphidodon luteobrunneus. Those specimens were all collected from Réunion, and their sequences are most similar to fish identified as Stegastes fasciolatus [¼ Plectroglyphidodon fasciolatus] (Collet et al., 2018: table 2). Plectroglyphidodon luteobrunneus is the only member of the fasciolatus clade known from the western Indian Ocean (Fricke, 1999; Heemstra et al., 2004; Letourneur et al., 2004; Fricke et al., 2009, 2018). This misidentification would explain the anomalous position of ‘‘ Pomacentrus agassizii ’’ seen in several studies (e.g., Hubert et al., 2011, 2012, 2017; DiBattista et al., 2016; Mirande, 2016; Rabosky et al., 2018). Of the species that we could not examine, each can be tentatively assigned to Stegastes sensu stricto based on the number of dorsal-fin spines, unpublished barcode sequences, previous statements in the literature, and/or geographic distribution. All remaining Atlantic and eastern Pacific species (S. leucorus, S. lubbocki, S. redemptus, S. sanctaehelenae, and S. uenfi) are retained in Stegastes sensu stricto. We follow Souza et al. (2016) in treating Stegastes sanctipauli as a synonym of S. rocasensis. Tree-based identifications (not shown) that assayed unreleased sequences in the BOLD database support this placement of S. leucorus, S. lubbocki, S. redemptus, and S. sanctaehelenae. Stegastes leucorus was most similar to S. beebei. This would corroborate the hypothesis of Allen and Woods (1980) who suggested that the two lineages (S. beebei as a subspecies of S. leucorus) plus S. baldwini are most closely related. Stegastes lubbocki and S. sanctaehelenae were found to be most similar to S. pictus and each other. Stegastes redemptus was linked to S. arcifrons in the NJ tree generated by BOLD. The Marquesan endemic Stegastes lividus is retained in Stegastes sensu stricto based on its possession of XII dorsal spines and overall resemblance to S. albifasciatus and S. nigricans (Randall, 2001, 2005)., Published as part of Tang, Kevin L., Stiassny, Melanie L. J., Mayden, Richard L. & DeSalle, Robert, 2021, Systematics of Damselfishes, pp. 258-318 in Ichthyology & Herpetology 109 (1) on pages 285-287, DOI: 10.1643/i2020105, http://zenodo.org/record/7846738, {"references":["Smith-Vaniz, W. F., B. B. Collette, and B. E. Luckhurst. 1999. Fishes of Bermuda: History, Zoogeography, Annotat- ed Checklist, and Identification Keys. American Society of Ichthyologists and Herpetologists, Lawrence, Kansas.","Vine, P. J. 1974. 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Impact of invasive species on native biota may be due to predation, competition for space or food, or indirect effects. Lionfish (Pterois volitans), invasive in the western Atlantic, is a voracious generalist predator, so it is expected to have a significant trophic overlap with native fishes of comparable size and habits. The goal of this study was to determine the diets of potential competitors of the lionfish, in particular a grouper, Cephalopholis cruentata (Graysby), and a snapper, Lutjanus apodus (Schoolmaster), and to compare them to the diet of lionfish in Xcalak, southern Mexican Caribbean. Stomach contents were analyzed and electivity and diet overlap were estimated. The trophic overlap between the lionfish and the two putative competitors, especially the grouper, was high, including prey that was consumed by the predators in higher proportion than the relative abundance of the prey in the environment, and probably at the same time of day. Lionfish and grouper shared as important diet items Stegastes sp., Halichoeres sp., Brachyura, and Palaemonidae, and most full stomachs were found during the early morning. The hypothesis of competition between them for particular prey is supported, so we advise to continue the culling programs of lionfish and also to monitor the abundance of the possible native competitors.

In the Gulf of California, mineral deposits have contributed to high metal contents in coastal environments. This study examined cadmium, lead, copper, zinc, and iron contents in three fish species, Kyphosus vaigiensis (herbivore), Stegastes rectifraenum (omnivore), and Balistes polylepis (carnivore) at two mining sites. Metal concentrations were analyzed by atomic absorption spectrophotometry and stable nitrogen and carbon isotopes were estimated using mass spectrophotometry. Also, we assessed the risk to human health from the consumption of these three species based on permissible limits, although only two of them (Kyphosus and Balistes) are consumed as food. Metal concentrations differed among fish species, except for iron. The highest concentrations of metals were not always recorded in the species at the highest trophic level, i.e., Balistes. The highest concentrations (dry weight) recorded were cadmium (0.21 &plusmn, 0.03 &micro, g g&minus, 1) and lead (1.67 &plusmn, 0.26 &micro, 1), in S. rectifraenum, copper (1.60 &plusmn, 0.49 &micro, 1) and zinc (67.30 &plusmn, 8.79 &micro, 1), in B. polylepis, and iron (27.06 &plusmn, 2.58 &micro, 1), in K. vaigiensis. Our findings show that each element accumulates differently in particular marine organisms, depending on the physiology of the species and the biogeochemistry of its habitat, which in turn is affected by the anthropogenic activities in adjacent areas. No risk of heavy metals toxicity is expected from the human consumption of the species and sites studied

Domesticator-domesticate relationships are specialized mutualisms where one species provides multigenerational support to another in exchange for a resource or service, and through which both partners gain an advantage over individuals outside the relationship. While this ecological innovation has profoundly reshaped the world’s landscapes and biodiversity, the ecological circumstances that facilitate domestication remain uncertain. Here, we show that longfin damselfish (Stegastes diencaeus) aggressively defend algae farms on which they feed, and this protective refuge selects a domesticator-domesticate relationship with planktonic mysid shrimps (Mysidium integrum). Mysids passively excrete nutrients onto farms, which is associated with enriched algal composition, and damselfish that host mysids exhibit better body condition compared to those without. Our results suggest that the refuge damselfish create as a byproduct of algal tending and the mutual habituation that damselfish and mysids exhibit towards one another were instrumental in subsequent mysid domestication. These results are consistent with domestication via the commensal pathway, by which many common examples of animal domestication are hypothesized to have evolved., It has been hypothesized that domestication can occur through the ‘commensal pathway’ in which the domesticate takes advantage of a niche created as a byproduct by the domesticator. Here, Brooker et al. provide evidence for a commensal domestication process between longfin damselfish and mysid shrimps.

Damselfishes of the genus Stegastes are some of the most abundant fish inhabiting shallow reef habitats. Although Stegastes play an important role in promoting primary production in reef ecosystems, their territories are known to favor the occurrence of bacterial pathogens. However, no studies so far have examined the microbiome composition of Caribbean Stegastes species. Here, we characterized the skin bacterial microbiome of juveniles and adults of Stegastes leucostictus and Stegastes adustus collected from La Parguera, Puerto Rico, and St. Thomas, US Virgin Islands. Our results showed that bacterial communities residing on the skin of Stegastes were related to taxonomy, environment and ontogeny. These results are in line with previous knowledge on the dynamics of fish skin microbiomes.

Coral reefs harbor the greatest biodiversity per unit area of any ecosystem on earth. While parasites constitute the majority of this biodiversity, they remain poorly studied due to the cryptic nature of many parasites and the lack of appropriate training among coral reef ecologists. Damselfishes (Pomacentridae) are among the most abundant and diverse fishes on coral reefs. In a recent study of blood parasites of Caribbean reef fishes, the first ever apicomplexan blood parasites discovered in damselfishes were reported for members of the genus Stegastes. While these blood parasites were characterized as “Haemohormidium-like”, they appear to be distinct from any other known apicomplexan. In this study, we examined host associations, geographic distributions, and provide further insights on the phylogenetic affiliation of this parasite. A combination of morphological characteristics and 18S rDNA sequences suggest that this parasite may be the same species at multiple sites and occurs from the southern to the northern extreme of the eastern Caribbean, although it appears rare in the north. At present it appears to be limited to members of the genus Stegastes and infects all life history stages. It is most common in benthophagous species that occur in high population densities and appears basal to a major monophyletic clade containing species of coccidia, distinct from the Piroplasmida, the order to which Haemohormidium spp. have been assigned. These findings suggest a possible fecal-oral mode of transmission., Graphical abstract Image 1, Highlights • A new species of Haemorhormidium-like apicomplexan blood parasite has recently been discovered in Caribbean damselfishes. • Morphological and molecular data indicate that it is widespread in the eastern Caribbean. • This parasite is limited to damselfish species of the genus Stegastes and infects juveniles and adults. • It is most common in benthophagous species that occur in high population densities. • This parasite resembles coccidia but 18S rDNA show it to be distinct from known genera, as well as genera of piroplasms.

The present study describes the cleaning interactions among species of cleaner gobies Tigrigobius spp. and Elacatinus puncticulatus (family Gobiidae) and the client fish species they clean in a coral reef of Gorgona Island, Colombia. In 419 cleaning events, we observed 27 species acting as clients of Tigrigobius spp., whereas only nine were clients of E. puncticulatus. Paranthias colonus and Cephalopholis panamensis were the species most commonly cleaned by Tigrigobius spp., while Ophioblennius steindachneri and Stegastes acalpulcoensis were the clients most commonly cleaned by E. puncticulatus. The abundance (but not the body size) of clients was an important variable predicting the cleaning frequency observed for clients of Tigrigobius spp., but this was not the case for clients of E. puncticulatus. Additionally, Tigrigobius spp. preferred cleaning planktivores, sessile invertebrate feeders and territorial herbivores (Ivlev's index >0·15), whereas E. puncticulatus did not exhibit any preference. We observed two major peaks of cleaning activity for Tigrigobius spp., one in the early morning and another one in the late afternoon. These results suggest that Tigrigobius spp. is a specialized cleaner goby, whereas E. puncticulatus is a facultative cleaner that cleans sporadically.