SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11280d6156db2e1de45c2c1004371d4646cdee24c1e9889f607944835f5a69cf' 
  AND token = 'AoeZpogplXVCDzujQV+6Tkg5SSRC2zk+DnXdWXa+/uo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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