SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a8574f8f9aad4db498049822105e0dd7953a95f4f3810460e2210165fda7ab8e' 
  AND token = 'ZguOHCXvzcOAeNigkMBMD+rmH+RMEorasJPQtFyIKqU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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