SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa1347d6051145d7f6a5b7f38d78ecf646f899387919d6a65949def08e056b58' 
  AND token = 'iRmQ1U3XDT0tt73MWD6J4JakPLgVrBs8ydUZ5a5qXBs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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