▁extensions ▁of ▁the ▁ce phal oth or ac ic ▁arm or ▁that ▁the ▁gener a ▁of ▁Am phi asp id idae ▁lack , ▁and ▁differ ▁from ▁am phi asp ido id ▁am phi asp ids ▁of ▁Gab rey asp id idae ▁in ▁that ▁gab rey asp id ids ' ▁mouth s ▁are ▁vent r ally ▁position ed , ▁whereas ▁the ▁mouth s ▁of ▁ol b ias pid ids ▁are ▁position ed ▁anterior ly . ▁ ▁Tax onomy ▁ ▁Ol b ias pis ▁This ▁is ▁the ▁type ▁genus ▁of ▁the ▁family , ▁and ▁has ▁two ▁species , ▁O . ▁co ales c ens , ▁and ▁O . ▁lat iss ima . ▁ ▁O . ▁co ales c ens ▁res emb les ▁a ▁hot ▁water ▁bott le ▁with ▁dor so - an terior ly ▁position ed ▁small ▁eyes ▁fl ank ed ▁by ▁pre orb ital ▁open ings , ▁and ▁a ▁prominent ▁d ors al ▁sp ine , ▁while ▁O . ▁lat iss ima ▁is ▁extremely ▁broad ▁in ▁comparison . ▁ ▁K ure yk as pis ▁K ure yk as pis ▁sale b ros a ▁has ▁a ▁compact ▁ce phal oth or ac ic ▁arm or ▁that ▁is ▁p ear - sh aped ▁( when ▁viewed ▁from ▁above ), ▁and ▁that ▁is ▁decor ated ▁with ▁distinct ive ▁rid ges ▁and ▁nod ules . ▁ ▁The ▁arm or ▁has ▁later al ▁wings ▁with ▁ser r ated ▁edges . ▁ ▁The ▁d ors al ▁sp ine ▁is ▁v estig ial ▁or ▁lack ing . ▁ ▁Ang ar as