SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25c2df1888951e8a747bf3efd0ecfcefd509e95d224b95efc8e8ab287efe3770' 
  AND token = 'srINpzanGfbo+YeVBLzmHBOnsk9I0S+7YhGdrbU9y44=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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