SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '16c9d5a953d17e40530fd15ed7e8bf9695b445e409b8443f433eb0e23a042660' 
  AND token = 'Chl268rl9WrfF9ucNZWhoa91ilqxZfGOVupXIEF7kpU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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