s ▁tail ▁is ▁el ong ated ▁and ▁later ally ▁com pressed ▁as ▁is ▁that ▁of ▁the ▁male ▁but ▁of ▁consider ably ▁shorter ▁length . ▁The ▁average ▁length ▁of ▁the ▁female ▁is ▁. ▁There ▁are ▁two ▁species ▁in ▁genus ▁Rhein ard ia . ▁The ▁Malays ian ▁R . ▁n ig res c ens , ▁inhab its ▁the ▁Malays ian ▁Ist hm us ▁and ▁the ▁Ann am ese ▁inhab its ▁the ▁Ann am etic ▁Mountain ▁Range . ▁Despite ▁being ▁sex ually ▁dim orph ic ▁gall iform ▁by ▁length , ▁the ▁male ▁only ▁we igh s ▁about ▁ 2 0 % ▁more ▁than ▁the ▁female . ▁The ▁average ▁weight ▁is ▁around ▁. ▁ ▁The ▁wings ▁of ▁the ▁cr ested ▁arg us ▁are ▁of ▁unusual ▁size ▁and ▁length ▁for ▁its ▁weight . ▁They ▁are ▁wide ▁and ▁square ▁like ▁those ▁of ▁Arg us ian us ▁versus ▁rounded ▁and ▁abbre vi ated ▁like ▁those ▁of ▁True ▁P he as ants . ▁Additionally , ▁there ▁is ▁no ▁disc ern ible ▁trailing ▁edge ▁secondary ▁wing ▁not ch ▁amongst ▁the ▁flight ▁fe athers , ▁indicating ▁a ▁capacity ▁of ▁sust ained ▁flight ▁in ▁species ▁of ▁this ▁genus . ▁Their ▁wings ▁are ▁morph olog ically ▁similar ▁to ▁the ▁wings ▁of ▁certain ▁semi - ar b ore al ▁C rac iformes , ▁particularly ▁Gu ans ▁of ▁the ▁genus ▁P ip ile . ▁The ▁feet ▁and ▁legs ▁of ▁cr ested ▁arg us ▁are ▁also ▁notable ▁in ▁the ▁presence ▁of ▁curious ly ▁developed ▁leg ▁scales ▁in ▁males ▁which ▁are ▁w iden ed ▁in ▁such ▁a ▁matter ▁that