SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9434ffd1fccf01815f82a724b717a01a3f98dbc6af6d4b374b683ed48cea65d9' 
  AND token = 'pYUG8lqNPTi/9LrPlNHt5wIrvR62+iVjD4kxjLrBB3M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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