No ontogenetic shift in the realised trophic niche but in Batesian mimicry in an ant-eating spider

Abstract

In predators an ontogenetic trophic shift includes change from small to large prey of several different taxa. in myrmecophagous predators that are also mimics of ants, the ontogenetic trophic shift should be accompanied by a parallel mimetic change. our aim was to test whether ant-eating jumping spider, Mexcala elegans, is myrmecomorphic throughout their ontogenetic development, and whether there is an ontogenetic shift in realised trophic niche and their mimetic models. We performed field observations on the association of Mexcala with ant species and investigated the natural prey of the ontogenetic classes by means of molecular methods. then we measured the mimetic similarity of ontogenetic morphs to putative mimetic models. We found Mexcala is an inaccurate mimic of ants both in the juvenile and adult stages. During ontogenesis it shifts mimetic models. the mimetic similarity was rather superficial, so an average bird predator should distinguish spiders from ants based on colouration. The realised trophic niche was narrow, composed mainly of ants of different species. There was no significant difference in the prey composition between ontogenetic stages. Females were more stenophagous than juveniles. We conclude that Mexcala is an ant-eating specialist that reduces its prey spectrum and shifts ant models during ontogenesis.

Overview of the Genetic Diversity of African Macrotermes (Termitidae: Macrotermitinae) and Implications for Taxonomy, Ecology and Food Science

“…Macrotermes natalensis had a maximum intraspecific p-distance of 3.72% and clustered in two genetic groups. As described above, G7 included M. natalensis from South Africa [34], M. natalensis from unreported geographic origin [43] and six of the new sequences from South Africa, and G2 included M. natalensis of unreported geographic origin [41] and M. falciger and M. subhyalinus from Kenya [40]. The existence of two species in M. natalensis has been noted previously in specimens collected in South Africa and Malawi [38].…”

“…Considering the overall results for the total dataset, i.e., the high level of incongruity between species names and genetic groups, the species identity of our specimens could not be inferred from the sequences (Figure 5). Our G7 sequences could represent M. natalensis, if the specimens at the origin of the sequences named M. natalensis (MK591923, AY818067 and AY818088) [35,41,43] were correctly identified by the authors of those studies. Similarly, our G3 sequences could represent specimens of M. falciger [42].…”

“…The sequences in G1 reportedly represent a tentative identification of specimens collected in Kenya [39]. Macrotermes subhyalinus also was part of three other genetic groups: G9 (intragroup maximum p-distance = 0.00%), which included M. subhyalinus sequences from Senegal [34]; G11 (intragroup maximum p-distance = 1.50%), which included one M. subhyalinus from the Ivory Coast [37,40] and Benin (Hausberger et al, 2011); in contrast, G2 (intragroup maximum p distance = 0.51%) included M. subhyalinus and M. falciger sampled from Kenya in the same study [40], and one M. natalensis of unreported geographic origin [41]. Therefore, it is likely that the sequences of M. subhyalinus represent four distinct species, in addition to the known differences between M. subhyalinus from East Africa and West Africa [38,40].…”

“…Macrotermes falciger from South Africa [42] clustered with 20 of the new sequences from South Africa in G3 (intragroup maximum p-distance = 0.33%). In G2 (intragroup maximum p-distance = 0.51%), M. falciger from Kenya [40] clustered with M. subhyalinus from Kenya [40] and one M. natalensis of unknown geographic origin [41].…”