SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0af71dd04f76c05a0f2a19740c55b7e7c877bad13946c9e002c30e1c46825a99' 
  AND token = '73Q0O/8xtIPxCsRYsROwPwoEy8qm90FE/IEVOTS9l4g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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