When decisions on homologous structures cause ambiguous taxa relationships: the Neomorphinae (Aves, Cuculidae) example

Abstract

The anatomy of Neomorphinae is poorly understood and the systematics of this sub-family is also the most controversial of the cuckoo taxa, mainly with regard to the systematic position of Tapera and Dromococcyx. In this study, morphological similarities of the Neomorphinae are discussed after a comprehensive description of the cranial osteology was conducted in seven species, embracing all the Neomorphinae genera. This description is followed by comparisons with other cuckoos in order to contribute to the anatomy and systematics of this sub-family. In this way, we provide illustrations that enable the osteological descriptions and the proposed primary homologies to be visualised and compared. Even though Neomorphinae species share many cranial osteological characteristics, there are some anatomical divergences that allowed us to divide them into two distinct groups: (Dromococcyx/ Tapera) and (Morococcyx(Neomorphus/Geococcyx)). After comparisons among all cuckoos this study suggests that Neomorphinae are more similar to Crotophaginae and Couinae than to other sub-families of cuckoos. Our results contrast with a recent phylogenetic study based on morphological features, mainly because alternative interpretations to the primary osteological homologies in this study grouped Tapera and Dromococcyx with Cuculinae. Although morphological studies can be used in phylogenetic analysis, we demonstrated here that decisions in the interpretation of the homologies can provide ambiguous results.Keywords: Neomorphinae, Cuculidae, cranial osteology, homology, phylogeny. Interpretações de homologias primárias e ambiguidade nas posições filogenéticas dos táxons: o exemplo nos Neomorphinae (Aves, Cuculidae) ResumoNeomorphinae é o grupo filogeneticamente mais controverso entre os cucos, em virtude da ambígua posição de Tapera e Dromococcyx, ainda, a anatomia do grupo é pouco compreendida. Neste estudo, as homologias primárias são discutidas em relação à osteologia craniana desta subfamília e comparadas aos demais Cuculiformes. O estudo propõe interpretações alternativas para homologias primárias dos caracteres cranianos em relação àquelas encontradas em filogenias com base nesta fonte de caracteres, na qual se observa Tapera e Dromococcyx agrupados dentro de Cuculinae. De modo a melhor demonstrar isto, os crânios foram descritos e ilustrados, apontando-se as homologias propostas e contrapondo-as com a literatura. Os resultados sugerem algumas variações entre os táxons que compõem a subfamília que permitem agrupá-los da seguinte maneira: (Dromococcyx/Tapera) e (Morococcyx(Neomorphus/ Geococcyx)). Ainda, comparando com as demais subfamílias, os Neomorphinae são similares a Crotophaginae e Couinae. Não obstante, os resultados demonstraram os táxons de Neomorphinae (incluindo Tapera e Dromococcyx) nitidamente mais similares entre si do que com qualquer outro grupo de cucos, indicando provável monofiletismo da subfamília, conforme sugerem os dados moleculares. No entanto a descrição da osteologia aqui apresentada difere do observ...

Biogeography on the early distribution of cuckoos (Aves: Cuculiformes)

“…The strict consensus cladogram from POSSO & DONATELLI (2006) diverges from the molecular data of SORENSON & PAYNE (2005), and osteological data from HUGHES (2000) also concerning the controversy regarding Taperinae position (POSSO & DONATELLI 2010). Phylogenetic studies (SIBLEY & AHLQUIST 1990, ARAGÓN et al 1999, SORENSON & PAYNE 2005 alternatively indicate them to be the most close related to Neomorphinae.…”

“…1). In some equally most parsimonious trees, Centropus is more closely related to the Neomorphinae, Crotophaginae and arboreal cuckoos (HUGHES 2000, POSSO & DONATELLI 2010. On the other hand, some trees indicate Centropus to be close related to Couinae (POSSO & DONATELLI 2010), as in SIBLEY & AHLQUIST (1990) and SORENSON & PAYNE (2005).…”

A survey of the uncinate bone and other poorly known ossicles associated with the lacrimal/ectethmoid complex of the avian skull

“…Burton (1969, p. 11) noted the presence of a well‐developed uncinate bone in Clamator , Eudynamys , and Centropus and “a short uncinate bone joining the palatine by means of a ligament” in Piaya , Ramphococcyx , and Crotophaga . An uncinate bone is also present in Neomorphus geoffroyi (Posso & Donatelli, 2010) and Coccycus ( Hyetornis ) rufigularis (Posso & Donatelli, 2007). However, the existing variability in the morphology of this ossicle was not addressed in earlier studies on the osteology of cuckoos (Hughes, 2000; Posso & Donatelli, 2006; Pycraft, 1903), and a number of taxa have not yet been studied.…”

Cucolepis cincta gen. n. et sp. n. (Cestoda: Cyclophyllidea) from the squirrel cuckoo Piaya cayana Lesson (Aves: Cuculiformes) from Paraguay

“…given that paruterinids parasitize a wide diversity of avian orders, from accipitriformes (hawks, eagles, kites and their allies) and caprimulgiformes (nightjars), to several families of Passeriformes (perching birds), cuckoos host a relatively small portion of paruterinid diversity. several studies have attempted to formally define the phylogenetic relationships among cuckoos using molecular, morphological, ecological and behavioural data (Hughes 1996(Hughes , 2000(Hughes , 2006 Bona and Maffi (1985) Francobona similita (Bona et Maffi, 1984) (Bona, Bosco et Maffi, 1986) Spasskii, 1991 trogoniformes Trogon violaceus gmelin Peru Bona et al (1986) Troguterina disparuncinata (Bona, Bosco et Maffi, 1986) Spasskii, 1991 trogoniformes Trogon curucui (l.) argentina Bona et al (1986) Johnson , Posso and Donatelli 2006, 2010 (Bona et Maffi, 1984) Georgiev et Kornyushin, 1994, two undescribed species within the "rectangula" group of Paruterina Fuhrmann, 1906 (sensu Bona and Maffi 1984a) and an unidentified species (see Bona and Maffi 1984a, b) of Triaenorhina. Coccycua is the only genus of the group for which members have not been examined yet for cestodes.…”