SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '589ec819e147169189d8bfa4aee876c316ac6a8b6f96cfc2162b4fb75fc6c8c1' 
  AND token = '5QRxWpYMm4nAEkvwzRvCIsVQ1vLt/ook+8hv6gB9bzw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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