SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '0bd8acbaf91436f36ca2acb9eb6eefdf30af653f7539329de5dd5bbab60361ea' 
  AND token = '7DiZRQBged9Wr2qPAlHDiqV9EsJrM/Npga7vwwzc8lU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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