SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9efd0025cf6301b12c262d298e4fc1cba3dfe9bbbc7ea29b53bd93825f112cd' 
  AND token = 'qCX42Xv7AL7q9k8bIsfXZIVjJp22ioc72pJ257QE7V4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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