SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '894488fe40bbb9b4e65e591874212789a09bb2b3473501b8b95b4f62e21de80b' 
  AND token = 'hxKJ8HOpBnHhddw2zthQTgOLau9l6G//VSTMKthF+iw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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