SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49209c8e3edc2ac642bd6b5139160ba569fbdf6a4f17a1318f73dcb6560930e4' 
  AND token = 'WUONyMAtCMRPi9dAcGYRDbb6On6SMuvbFLrFtJdxeF8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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