SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3e539a86ac7e3c28f0651269008e7b4542855db1d31d5f4df32a3374c9c3d3aa' 
  AND token = 'u6rCkRyyruvjp8p2kpbVxHiD6wOtC5A190o42z/I/P8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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