SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0cbe2b7dfe0320ff0195355d8f2dca1a55201905dabd0aeddaf2eeff1e48382c' 
  AND token = 'vb9eKxt+R3jvn0jfJLHqCgUWQPUa5YkIYh5nQ1foRd8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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