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The use of species as the unit of organismal identification has implications for policies that support conservation and management. For most fish, including tilapiine cichlids, identification in the last century supported by alpha taxonomy produced keys and descriptions of diagnostic features and designation of correct species names. The rapid increase in species discoveries in the twenty-first century has resulted in large turnover of names and descriptions. However, these updates have had little impact on conservation of tilapiine cichlids, mostly because the wide distribution of cichlid species provides the false impression of resilience to habitat disturbance. There is a need to provide clarity on intraspecific variations, in order to conserve cichlid populations threatened by species introductions and habitat loss. Here, we review some powerful tools that assess differences in morphology, trophic ecology, and genomics and enable definition of units of conservation of tilapiine cichlids. We discuss advances in geometric morphometrics in morphological characterization of tilapiine cichlids. Similarly, we show how sequencing technology has influenced the definition of units of conservation, namely evolutionary significant units, which take into account gene flow between populations, and recognize demography and migrations. We also highlight next generation sequencing technology that is revolutionizing biomonitoring using environmental DNA.

Non-native species have been widely distributed across Africa for the enhancement of capture fisheries, but it can be unclear what benefits in terms of fisheries production the non-native species bring over native species. Here we compared the relative growth rate of sympatric populations of introduced Oreochromis niloticus (Nile tilapia) to indigenous Oreochromis jipe (Jipe tilapia) at three impoundments in Northern Tanzania. Using scale increments as a proxy for growth, we found that O. niloticus had an elevated growth rate relative to O. jipe, with the greatest O. niloticus growth rates being evident in the Nyumba ya Mungu reservoir. These results help explain why O. niloticus may be a superior competitor to native species in some circumstances. However, further introductions of this non-native species should be undertaken with caution given potential for negative ecological impacts on threatened indigenous tilapia species.

A bacterial strain, designated Ruye-71T, was isolated from a freshwater tilapiine cichlid fish culture pond in Taiwan and characterized in a taxonomic study using a polyphasic approach. Cells of strain Ruye-71T were Gram-stain-negative, strictly aerobic, yellow-pigmented rods that were motile by gliding. Growth occurred at 10–30 °C (optimum, 15–30 °C), at pH 7.0–8.0 (optimum, pH 8.0) and with 0–2 % NaCl (optimum, 0–1 %). Phylogenetic analyses based on 16S rRNA gene sequences showed that strain Ruye-71T belonged to the genus Flavobacterium and was most closely related to Flavobacterium defluvii EMB117T, with a 16S rRNA gene sequence similarity of 97.7 %. Strain Ruye-71T contained iso-C15 : 0, summed feature 3 (comprising C16 : 1ω6c and/or C16 : 1ω7c), C16 : 0, C16 : 0 3-OH, iso-C15 : 0 3-OH and iso-C17 : 0 3-OH as major fatty acids. The major isoprenoid quinone was MK-6. The polar lipid profile consisted of phosphatidylethanolamine and several unidentified polar lipids. The DNA G+C content of the genomic DNA of strain Ruye-71T was 39.2 mol%. The mean level of DNA–DNA relatedness between strain Ruye-71T and Flavobacterium defluvii DSM 17963T was 39.9±1.2 %. On the basis of phylogenetic inference and phenotypic data, strain Ruye-71T should be classified as representing a novel species, for which the name Flavobacterium tilapiae sp. nov. is proposed. The type strain is Ruye-71T ( = BCRC 80262T = KCTC 23312T). Emended descriptions of Flavobacterium defluvii and Flavobacterium johnsoniae are also proposed.

Seasonal (semestral) counts of aquatic birds at five Andean lakes in Ecuador (Colta, La Mica, Yambo, Yahuarcocha and San Pablo) were analyzed to detect trends in population size between 2004 and 2011.Trends of four abundant species (Ardea alba, Anas georgica, Fulica ardesiaca and Oxyura jamaicensis) and those of five functional groups (based upon body size and diet) were tested using generalized additive mixed modeling. In total, 19 bird species were consistently recorded over the whole period. The Andean Coot (F. ardesiaca) was found in highest densities (c. 3 birds per ha at Colta and Yambo). No significant trends were detected. However, the counts of functional groups exhibited a seasonal pattern (higher counts in February than in July), possibly due to lower resource availability in the dry season. Piscivorous species were relatively abundant at one lake (Yahuarcocha), which might be related to the introduction of Tilapiine cichlid fishes.

Abstract Phenotypic plasticity is the capacity of an organism's phenotype to vary in different environments. Although diet-induced phenotypic plasticity has been documented in New World cichlids, it has been hypothesised that this type of plasticity would be limited in certain Old World cichlids, because of the morphological constraints on the jaw imposed by mouth-brooding. This hypothesis was experimentally tested by determining the effect of different diets on the head and jaw morphology of split broods of several species of haplochromine cichlids from Lake Malaŵi, Africa, and two substrate-spawning cichlids, one from the Old World, Tilapia mariae (Boulenger), and one from the New World, Herichthys cyanoguttatum (Baird and Girard). Different feeding regimes resulted in differences in head morphologies in both New and Old World cichlid species. Although Old World mouth-brooding haplochromine cichlids exhibited phenotypic plasticity, the magnitude of head-shape plasticity observed was greater in the New World substrate-spawning cichlid, H. cyanoguttatum . The Old World tilapiine cichlid, T. mariae , did not exhibit phenotypic plasticity of head morphology. Experiments with modified foods demonstrated that the observed changes were unrelated to dietary nutrition, but were a result of differing feeding modes. Phenotypic plasticity might have contributed to the extensive trophic radiation and subsequent explosive speciation observed in Old World haplochromine cichlids. The existence of phenotypic plasticity has implications for morphology-based species descriptions as well.

A new species of tilapiine cichlid, Oreochromis lorenzoi, is described from the late Miocene (Messinian) of central Italy. This species is represented by four articulated specimens and a caudal region of a fifth individual. Oreochromis lorenzoi, sp. nov. is the earliest confirmed representative of the genus Oreochromis, and it is the first European fossil cichlid. Oreochromis lorenzoi and additional examples from other fossil fishes provide evidence of faunal exchanges between Africa and the northern coasts of the Mediterranean during the Miocene. Paleoenvironmental implications are also discussed.

Fatty acid composition in the muscle of eight endemic haplochromine cichlids and one tilapiine cichlid from Lake Malawi was studied by gas-liquid chromatography. The species studied represent a wide variety of niches: Algae combing, shell crushing, feeding on littoral and semipelagic zooplankton, detecting invertebrates hidden in the sediment using expanded lateral line canals, and fish predation in littoral and bathypelagic zones. The sampling was done during the early rainy season. The analysis of fatty acid composition suggests that, despite the reported plasticity in feeding, the niches of the species studied are established and stable. The proportion of eicosapentaenoic acid (20:5n-3) in relation to arachidonic acid (20:4n-6) illustrated the position of these species in the foodweb: equal proportions in algae feeders and clear 20: 4n-6 dominance in species feeding on benthic prey. Although the number of replicates was small, discriminant analysis with 31 fatty acids separated the specimens into dense centers according to species. These results encourage the use of chemometric methods for studying ecological relationships among freshwater fauna and ongoing evolutionary processes.

The Middle Awash sites in Ethiopia, known for the find of one of the earliest known hominids—†Ardipithecus ramidus—have also yielded many fish and other vertebrate fossils. The Middle Awash locality has sites ranging from late Miocene through to the Pleistocene, and provides the first extensive record of fossil fish in Ethiopia. This ichthyofauna includes many specimens of a tilapiine cichlid referable to the living genus Oreochromis. These cichlids are here described as a new species, †Oreochromis (Oreochromis) harrisae, based on several osteological characters. The relationships of tilapiine cichlids are not well established. Few osteological studies of tilapiine cichlids have been done, and those that have tend to concentrate on pharyngeal characters that are phylogenetically useful at the generic and specific level, but not as useful at higher levels. The characters used in this paper may be useful to determine relationships among genera within the Tilapiini.

We estimated a novel phylogeny of tilapiine cichlid fish (an assemblage endemic to Africa and the Near East) within the African cichlid fishes on the basis of complete mitochondrial NADH dehydrogenase subunit 2 (ND2) gene sequences. The ND2 (1,047 bp) gene was sequenced in 39 tilapiine cichlids (38 species and 1 subspecies) and in an additional 14 nontilapiine cichlid species in order to evaluate the traditional morphologically based hypothesis of the respective monophyly of the tilapiine and haplochromine cichlid fish assemblages. The analyses included many additional cichlid lineages, not only the so-called tilapiines, but also lineages from Lake Tanganyika, east Africa, the Neotropics and an out-group from Madagascar with a wide range of parental care and mating systems. Our results suggest, in contrast to the historical morphology-based hypotheses from Regan (1920, 1922 ), Trewavas (1983), and Stiassny (1991), that the tilapiines do not form a monophyletic group because there is strong evidence that the genus Tilapia is not monophyletic but divided into at least five distinct groups. In contrast to this finding, an allozyme analysis of Pouyaud and Agnese (1995), largely based on the same samples as used here, found a clustering of the Tilapia species into only two groups. This discrepancy is likely caused by the difference in resolution power of the two marker systems used. Our data suggest that only type species Tilapia sparrmanii Smith (1840) should retain the genus name TILAPIA: One particular group of tilapiines (composed of genera Sarotherodon, Oreochromis, Iranocichla, and Tristramella) is more closely related to an evolutionarily highly successful lineage, the haplochromine cichlids that compose the adaptive radiations of cichlid species flocks of east Africa. It appears that the highly adaptable biology of tilapiines is the ancestral state for all African cichlids and that the more stenotypic lifestyle of the haplochromine cichlids is derived from this condition. We reconstructed the evolution of the highly variable parental care systems on the basis of the most inclusive composite phylogeny to date of the African, Neotropical, and Madagascan cichlids with special emphasis on a group of tilapiines comprising the substrate-spawning genus Tilapia, and the mouthbrooding genera Sarotherodon and OREOCHROMIS: We demonstrate several independent origins of derived mouthbrooding behaviors in the family Cichlidae.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:19:59Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:44:50Z : No. of bitstreams: 1 2-s2.0-0034510558.pdf: 691173 bytes, checksum: 1736dcd6be20d2aefbe5a6897b8cb422 (MD5) Made available in DSpace on 2014-05-27T11:19:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2000-12-01 In this study, we report the cloning and nucleotide sequence of PCR-generated 5S rDNA from the Tilapiine cichlid fish, Oreochromis niloticus. Two types of 5S rDNA were detected that differed by insertions and/or deletions and base substitutions within the non-transcribed spacer (NTS). Two 5S rDNA loci were observed by fluorescent in situ hybridization (FISH) in metaphase spreads of tilapia chromosomes. FISH using an 18S rDNA probe and silver nitrate sequential staining of 5S-FISH slides showed three 18S rDNA loci that are not syntenic to the 5S rDNA loci. Department of Biology Dalhousie University, Halifax, NS B3H 4J1 Departamento de Genktica e Evoluqlo Universidade Federal de Slo Carlos, Slo Carlos, SP Departamento de Morfologia Instituto de Biocihcias Universidade Estadual Paulista, Botucatu, SP Departamento de Morfologia Instituto de Biocihcias Universidade Estadual Paulista, Botucatu, SP