aris , ▁with ▁between ▁one ▁and ▁three ▁species , ▁which ▁comes ▁from ▁the ▁south - west ▁And e an ▁region ▁of ▁South ▁America , ▁is ▁considered ▁the ▁sister ▁to ▁the ▁rest ▁of ▁the ▁family . ▁Some ▁authors ▁separate ▁H ys pe och aris ▁as ▁a ▁mon og ener ic ▁family ▁Hyp se och ar it aceae , ▁while ▁older ▁sources ▁placed ▁it ▁in ▁the ▁Ox al id aceae . ▁The ▁genus ▁Rh yn ch othe ca ▁has ▁also ▁been ▁separated ▁into ▁the ▁Viv ian ia ceae . ▁ ▁The ▁Ger ania ceae ▁have ▁a ▁number ▁of ▁gen etic ▁features ▁unique ▁amongst ▁ang ios per ms , ▁including ▁highly ▁re arr anged ▁pl ast id ▁genom es ▁differ ing ▁in ▁gene ▁content , ▁order ▁and ▁expansion ▁of ▁the ▁invert ed ▁repeat . ▁ ▁Ph y log eny ▁ ▁Rec ent ▁comparison ▁of ▁DNA - f rag ments ▁resulted ▁in ▁the ▁following ▁ph y log en etic ▁tree . ▁ ▁Distribution ▁and ▁habitat ▁▁ ▁Most ▁species ▁are ▁found ▁in ▁temper ate ▁or ▁warm ▁temper ate ▁regions , ▁though ▁some ▁are ▁tropical . ▁Pel arg on ium ▁has ▁its ▁centre ▁for ▁divers ity ▁in ▁the ▁Cape ▁region ▁in ▁South ▁Africa , ▁where ▁there ▁is ▁a ▁striking ▁veget ative ▁and ▁fl oral ▁variation . ▁ ▁Gallery ▁ ▁References ▁ ▁Bibli ography ▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁ ▁Sand ro ▁P ign atti , ▁Flora ▁d ' Italia , ▁Ed agr icole , ▁Bolog na ▁ 1 9 8 2 . ▁▁ ▁Bak ker , ▁F . T ., ▁C ul ham ,