SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8fe9559b9058c797731c234dc831303fbec7da506bf86ec77e8260212d0d75c2' 
  AND token = 'Vrw8+XUkfSQLU+kMttI4/loZYjOIn6UjP9uB+ELNmWI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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