Description of Poecilia (Acanthophacelus) Wingei N
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Contributions to Zoology, 74 (1/2) 97-115 (2005) Description of Poecilia (Acanthophacelus) wingei n. sp. from the Paría Peninsula, Venezuela, including notes on Acanthophacelus Eigenmann, 1907 and other subgenera of Poecilia Bloch and Schneider, 1801 (Teleostei, Cyprinodontiformes, Poeciliidae) Fred. N. Poeser1, Michael Kempkes2, Isaäc J. H. Isbrücker1 1 Zoological Museum Amsterdam, University of Amsterdam, P.O. Box 94766, 1090 GT, Amsterdam, The Nether- lands, e-mail: [email protected]; 2 Am Mühlenberg 25, D-46419 Isselburg – Anholt, Germany Keywords: Guppies, Poecilia reticulata, P. wingei, melanophore patterns, character displacement, Paría Peninsula, despeciation Abstract Remarks on the 'Endler’s live-bearer' ...................................... 113 Acknowledgements ..................................................................... 114 The taxonomy of the common guppy, Poecilia reticulata Peters, References ..................................................................................... 114 1859, is reviewed and the closely related Campoma guppy, P. wingei n. sp., is described. Formerly, the common guppy was not judged to be closely related to any other species of Poecilia, but Introduction the new species is the second species to be allocated in the sub- genus Acanthophacelus Eigenmann, 1907. The recognition of P. wingei results from observed character displacement, i.e., on the The common guppy, Poecilia reticulata Peters, 1859, interaction between two closely related species in a shared envi- has a long history as a monotypic taxon. Poeser ronment. In addition to differences in coloration, behaviour also (2003, chapter 11) considered Poecilia Bloch and indicates specific differences. The area in whichP. wingei occurs, Schneider, 1801 as a monophyletic assemblage of the Campoma region at the base of the Paría Peninsula in Vene- nine morphological distinct species groups, all with zuela, hints to an origin of the subgenus Acanthophacelus prior their own evolutionary origin but with no species to the uplift of the Cordilleras, i.e., the eastern orogenesis of the Andes. Moreover, an explanation is offered for aberrant molecu- group more related to one group or the other. Because lar data in Trinidadian guppies. the morphological distinctions are sometimes quite remarkable, a further in-group analysis was per- formed (Poeser, unpubl.) and the apparent autapo- Contents morphies for P. reticulata (cf. Poeser, 2003, chapter 9) proved to be synapomorphies for P. reticulata and Introduction ..................................................................................... 97 the species described as new herein. The subgenus Methods .......................................................................................... 99 Acanthophacelus Eigenmann, 1907 is again recog- Material .......................................................................................... 99 nised based on these synapomorphies (cf. Poeser and Collection data of the 2002 expedition ............................. 102 Systematic section ....................................................................... 103 Isbrücker, 2002; Poeser and Isbrücker, in Poeser, Poecilia (Acanthophacelus) wingei n. sp. ........................ 103 2003), prompting a re-examination of all species Characterization of the genus Poecilia ............................. 105 groups mentioned in Poeser (2003, chapter 9). Characterization of the subgenus Acanthophacelus ....... 105 Poecilia (Acanthophacelus) reticulata is a well- Comparison of the colour patterns between the known little fish, whereas its taxonomic allocation subgenera Acantophacelus and Micropoecilia .......... 106 Spatial distribution of the phenotypes of the was fuzzy. Based on a single female, Peters (1859) freshly collected guppies ................................................ 108 allocated a new species from Venezuela to the genus Evidence of character displacement .................................. 108 Poecilia, viz., P. reticulata. Since Peters (1859) did Behavioural differences between Poecilia reticulata and not mention more specimens, the taxonomic status P. wingei ................................................................................... 109 of this species is based on this single specimen (Poe- Behaviour of the common guppy ....................................... 109 ser and Isbrücker, 2002; Poeser and Isbrücker, in Behaviour of the Campoma guppy .................................... 109 Remarks on population differentiation in Trinidadian Poeser, 2003, chapter 6). In addition, conspecific guppies ..................................................................................... 111 specimens from the same lots as the holotype (topo- Downloaded from Brill.com10/03/2021 06:40:05AM via free access 98 F.N. Poeser et al. – A new guppy from Venezuela types) were shipped by Peters from Berlin to London P. reticulata. He established his Mollienesia on the (Paepke, 1986). They were recorded by Günther basis of the terminal hooks on the gonopodium and (1866) as Girardinus reticulatus, and were compared Poecilia by the bumps on ray 4a. Poecilia reticulata to Girardinus guppii Günther, 1866. Girardinus Poey, possesses both a hook on the gonopodium and has a 1854 (type species, G. metallicus Poey, 1854), is a ‘bumpy’ gonopodial ray 4a, i.e., it has both of the valid genus, distantly related to Poecilia. The type above features. Rodriguez (1997: 673) thus was con- material of Girardinus guppii was examined (Poeser, tradicting his own character assessment. Also phylo- submitted manuscript) and confirmed as identical to genetic analyses based on molecular data (Ptacek and P. reticulata. Breden, 1998; Breden et al., 1999) did not render a Eigenmann (1907) examined specimens collected resolved taxonomy. Moreover, the latter phylogeny from Barbados and Guyana. He allocated the guppy clustered P. reticulata with P. parae and P. picta, to a distinct genus, viz., Acanthophacelus Eigenmann, separating these species from the remaining species 1907, mainly based on structures of the gonopodial of Poecilia. Based on the very distinct morphology tip. Eigenmann (1907) designated Poecilia reticu- that is presented in this paper, we hold the guppy dis- lata Peters, 1859 type species for his new genus. tinct from the other species of Poecilia and we split In a breeding report concerning guppies in the P. reticulata and the new species off from the species Royal Botanical Gardens in London, Boulenger of Micropoecilia, viz., P. parae Eigenmann, 1894, P. (1912) mentioned guppies as the only freshwater fish branneri Eigenmann, 1894, P. bifurca (Eigenmann, on Barbados, which island was the alleged type local- 1909), P. picta Regan, 1913 and P. minima Costa and ity of Lebistes poecilioides De Filippi, 1861, thus Sarraf, 1997. Differences between P. reticulata, P. naming this species Girardinus poecilioides. Regan parae and P. branneri are summarised in Table II. (1913) changed this by re-naming this species Lebi- Another method to unravel taxonomic difficulties stes reticulatus. Lebistes remained monospecific is to study behavioural patterns, preferably under until Rosen and Bailey’s (1963) revision of the Poe- natural conditions (Clark and Aronson, 1951; Liley, ciliidae, in which Poecilia (Lebistes) reticulata was 1966). Studies on guppy behaviour yielded a standard joined in one subgenus with four species of Micro- description for mating behaviour in P. reticulata (cf. poecilia Hubbs, 1926 (Table I), and with Cnesterodon Baerends et al., 1955; Table III). Because the initial scalpridens Garman, 1895. The latter species was attempts to distinguish a new species of guppies re-allocated by Costa (1991) as Pamphorichthys based on preserved material was inconclusive, it was scalpridens, whereas Poecilia (Micropoecilia) was decided to make field observations on behavioural considered as a distinct genus by Meyer (1993). aspects, in order to gain insight on possible specific Thereafter, the guppy largely remained in the mono- differentiations. Collection data of this field trip are specific subgenus Lebistes, although not without herein presented separately from the materials exam- debate (cf. Costa and Sarraf, 1997; Poeser and Is- ined prior to this journey. brücker, 2002; Poeser and Isbrücker, in Poeser, Detailed information on guppy populations is 2003). fragmented and concerns examinations on a local The phylogenetic analysis of Rodriguez (1997) scale, e.g., Trinidad. General information on mor- did not adequately resolve the taxonomy concerning phometric and pigmentational data comprising the Table I. Allocation of species of the subgenus Lebistes sensu Rosen and Bailey, 1963. Poecilia reticulata Peters, 1859 Poecilia (Acanthophacelus) reticulata Poecilia wingei n. sp. Poecilia (Acanthophacelus) wingei Poecilia parae Eigenmann, 1894 Poecilia (Micropoecilia) parae Poecilia branneri Eigenmann, 1894 Poecilia (Micropoecilia) branneri Poecilia bifurca (Eigenmann, 1909) Poecilia (Micropoecilia) bifurca Poecilia picta Regan, 1913 Poecilia (Micropoecilia) picta Poecilia minima Costa and Sarraf, 1997 Poecilia (Micropoecilia) minima Poecilia scalpridens Garman, 1895 Pamphorichthys scalpridens (cf. Costa, 1991). Downloaded from Brill.com10/03/2021 06:40:05AM via free access Contributions to Zoology, 74 (1/2) – 2005 99 total natural range of variation in guppies is not (number of individuals measured; range of measurements): fully comprehended, although local studies have average. provided information on evolutionary