SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6b39002a50a2ff3beb36e172335272f6e9fc55326d9ec6fb793486a8f7ac44a8' 
  AND token = 'GhHPnGIctj+Lsh611BFyF3PtXGJvsWkJvhIuQsWwNEA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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