A new species of slender skink is described from the Philippines. The species is endemic to Lubang Island, and is assigned to the Brachymeles bonitae Complex based on phenotypic and genetic data. Specimens were collected from Lubang Island between 1991 and 2012, and were examined based on morphological data (qualitative traits, meristic counts, and mensural measurements). Published genetic sequence data from phylogenetic studies of the genus reveal the new species to be highly divergent from congeners. Brachymeles ligtas sp. nov. is differentiated from other members of the genus based on a number of distinct morphological features, including small body size (SVL 60.7-79.6 mm), bidactyl fore-limbs, digitless hind limbs, high number of presacral vertebrae (50), and the absence of auricular openings. Additionally, the new species has diagnostic, distinct dorsal head scale patterns. This new species becomes the only member of the genus known to occur on the deep-ocean island of Lubang.

Kin selection explains conditions under which closely related individuals should be less antagonistic towards one another. One benefit of kin selection is a reduction in aggression towards kin in various social contexts, such as foraging. In the gynogenetic Amazon molly, females have been shown to differentiate between clone types, preferring to associate with clonal sisters to non-sisters, regulating their aggressive behaviours accordingly. We ask if Amazon mollies in resource-limited environments retain the ability to regulate aggressive behaviours according to relatedness. We found that focal females regulated their aggressive behaviours depending on partner type. Females spent more time behaving aggressively towards the heterospecific females than either of the clonal lineages, and towards non-sister clones compared to clonal sisters. We are able to confirm that kin discrimination is maintained, resulting in females showing more aggression towards heterospecific females and non-sister clones in a food-limited environment, and that this aggression scales with relatedness.

0SHORT TITLE: Food Competition in a Clonal Fish. LAY SUMMARY: 5Kin recognition allows individuals to adjust costly behaviors, such as aggression, according to the degree of genetic relatedness. We show that in a food-limited environment, a clonal species of fish, the Amazon molly, females regulate aggressive behaviors depending on how closely related they are to the recipient female, behaving more aggressively to both heterospecific females and non-sister clones. The ability to regulate costly behaviors under variable social 2 0 conditions is advantageous, especially when resources are limited. ABSTRACT:. CC-BY-NC-ND 4.0 International license It is made available under a was not peer-reviewed) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.The copyright holder for this preprint (which . http://dx.doi.org/10.1101/057018 doi: bioRxiv preprint first posted online Jun. 3, 2016; 2 Kin selection theory predicts that closely related individuals should be more altruistic and less antagonistic towards one another. In addition, it would predict that the higher the relatedness value 2 5 (R) between individuals, such as in clonal organisms, the more likely kin selection is to evolve.One benefit of kin selection is a reduction in aggression towards kin in various social contexts, such as foraging. In the gynogenetic Amazon molly, Poecilia formosa, females have been shown to differentiate between clone types, preferring to associate with clonal sisters to non-sisters, and regulate their aggressive behaviors accordingly. We ask if Amazon mollies in resource-limited 3 0 environments: 1) still maintain the ability to regulate aggressive behaviors according to relatedness (heterospecific females, clonal sisters or non-sisters), and 2) how their aggressive behaviors change relative to a female's social partner? Using a repeated-measures design, we found that focal females regulated their aggressive behaviors depending on partner type (i.e., a heterospecific female, clonal sister, or non-sister). Heterospecific females and the non-sister 3 5clones spent more time behaving aggressively towards the focal females, and these females also received significantly more bites from heterospecific females. Interestingly, the clonal sisters, when compared to the other two female types, performed significantly more tail beats towards focal females. We are able to confirm that females do show more aggression towards heterospecific females and non-sister clones in a food-limited environment, and that their 4 0 aggression scales with relatedness (R).