SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e09bc13cc8a76dbecc9f77940b3555dc764f4afeaef57b170269610dd0aadbf5' 
  AND token = 'SR+zDC9w3cB9EYMYae0MjKCAqK6fdXyP0McgLAsGG6M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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