SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1c6c4486599143abcc64f9b596999fa73d8106fe334991c0f29eb666ce9431f' 
  AND token = 'gzI+baLUsIYwaYQMhBfyvfMQDmiUVFphOACLPGeq++w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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