Cryptic Speciation in Brazilian Epiperipatus (Onychophora: Peripatidae) Reveals an Underestimated Diversity among the Peripatid Velvet Worms

Abstract

BackgroundTaxonomical studies of the neotropical Peripatidae (Onychophora, velvet worms) have proven difficult, due to intraspecific variation and uniformity of morphological characters across this onychophoran subgroup. We therefore used molecular approaches, in addition to morphological methods, to explore the diversity of Epiperipatus from the Minas Gerais State of Brazil.Methodology/Principal FindingsOur analyses revealed three new species. While Epiperipatus diadenoproctus sp. nov. can be distinguished from E. adenocryptus sp. nov. and E. paurognostus sp. nov. based on morphology and specific nucleotide positions in the mitochondrial cytochrome c oxidase subunit I (COI) and small ribosomal subunit RNA gene sequences (12S rRNA), anatomical differences between the two latter species are not evident. However, our phylogenetic analyses of molecular data suggest that they are cryptic species, with high Bayesian posterior probabilities and bootstrap and Bremer support values for each species clade. The sister group relationship of E. adenocryptus sp. nov. and E. paurognostus sp. nov. in our analyses correlates with the remarkable morphological similarity of these two species. To assess the species status of the new species, we performed a statistical parsimony network analysis based on 582 base pairs of the COI gene in our specimens, with the connection probability set to 95%. Our findings revealed no connections between groups of haplotypes, which have been recognized as allopatric lineages in our phylogenetic analyses, thus supporting our suggestion that they are separate species.Conclusions/SignificanceOur findings suggest high cryptic species diversity and endemism among the neotropical Peripatidae and demonstrate that the combination of morphological and molecular approaches is helpful for clarifying the taxonomy and species diversity of this apparently large and diverse onychophoran group.

Macroperipatus ohausi: redescripción y notas taxonómicas sobre su estatus (Onychophora: Peripatidae)

“…The sensory bristles usually are needleshaped and curved posteriorly, as observed in E. acacioi, E. machadoi and E. ohausi. However, it is spine-shaped in the cryptic species from Minas Gerais (Oliveira et al, 2011). The range of leg pairs is different among these six Brazilian Southeastern species.…”

“…A-D) were compared to the specimens from RPPN dos Petroleiros and also agree with them in morphology. The morphology of the dorsal primary papillae and the range of leg pairs show that Epiperipatus ohausi is more closely related to the species of Epiperipatus from the state of Minas Gerais (Southeastern Brazil): E. acacioi, E. machadoi, E. diadenoproctus Oliveira, Lacorte, Fonseca, Wieloch & Mayer, 2011; E. adenocryptus Oliveira et al 2011;and E. paurognostus Oliveira et al 2011. Epiperipatus ohausi has seven or eight scale ranks on the base of the primary papillae, while E. acacioi, E. machadoi, E. diadenoproctus, E. adenocryptus have 5-6, 5-8, 5-8 and 5-7, respectively.…”

“…The range of leg pairs is different among these six Brazilian Southeastern species. In increasing order, the ranges are: 27 to 29 in E. ohausi; 25 to 28 in E. acacioi (n=34); 26 to 29 in E. paurognostus (n=15, see Oliveira et al, 2011);26 to 30 in E. adenocryptus (n=25, see Oliveira et al, 2011);E. diadenoproctus (n=62, see Oliveira et al, 2011), and 27 to 31 in E. machadoi (n=21).…”

ONICÓFORO Peripatus sp. (ONYCHOPHORA: PERIPATIDAE) COMO INDICADOR DE CONECTIVIDADE NA PAISAGEM CACAUEIRA NO SUDESTE DA BAHIA, E SUA IMPORTÂNCIA PARA A CONSERVAÇÃO

“…Apesar de terem uma origem marinha remota (Tait et al, 1995), todos onicóforos atuais são terrestres. São invertebrados com taxonomia complexa (SampaioCosta et al, 2009;Oliveira et al, 2011) Oliveira et al, 2011).…”

“…Por possuírem espiráculos permanentemente abertos e uma cutícula extremamente permeável, somente vivem em locais úmidos. São encontrados de preferência na serapilheira de formações florestais, dentro ou embaixo de troncos, ou ainda em cavernas, onde caçam pequenos invertebrados que capturam graças à projeção de um jato de muco pegajoso, secretado pelas glândulas cefálicas (Oliveira et al, 2011).…”