Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d28562f0cad80cf81d07f92faf2178a832bd043e42749b8ac12375ebfb11cb2' 
  AND token = 'TDZ1EgH3q94QwuipRmcFpyvZ4dAFKDa2oPRYqHmc+BQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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