SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1fb8e64cc2b0b967ea98e94af13c2debf6277985b3d11e0496bc5b5d7a3ada98' 
  AND token = 'GEswZns0oQaDINXL6XWxHSzuJ/JamjKA04YyNQ6cn8o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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