SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddefb1781849f3b97e2d092fa88f287e2d92cd9bae004c0b6569004660cf3787' 
  AND token = 'C4p/iSDG9mZFVzMgqdBo9PvPQF0Vew3mrq938LpIUow=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00064

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}