SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0c128966bf852f7008a5056e1af06d30d58bb5ba707d0b4888f1d84fa8f27f2' 
  AND token = 'VdSVtxqZAn34+gnouIPvxaR3MR9AkCTgSp+a+vR4CbY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables