SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fead7bdbf5ce502abf0017f4977901af29ed810b56411c3dc22fd6aa4b9cd3bf' 
  AND token = 'XdWJaA1p4yly+sVSB4MoPKHupB4handUw4+p3gOEa+M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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