SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8d68ea3e4b285991413bae2565c3449f179e63f80c7afa0de9757b7394d161b3' 
  AND token = '2ns7OtT5uR+n/rfFyJ5w4NbNY2IsUId5GeA2vXqVh/E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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