SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5505a446afa9bec55c34858b1350fea357fe6fb3da20e30d75f811a08127a602' 
  AND token = 'bKE6Lu0HYkx1AlC/yEK4SLX6YogBWuIA3p11GQKFqQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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