SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c0d0c171fbe5a889df36c7a611e101a35bf61e181c25161008fe0dfdc9cd2bb' 
  AND token = 'gXSuW+HssZhNCG4COhuVLnCJWdKrMdOjOxjbHxrcHt0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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