SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd5521c4c3ab07f535bd566daa51fafeae8ef47075a977d8ab2b46fcb6d17062b' 
  AND token = 'sSoeDIPDrLRisG0jgE/Mx54cvGfLqyDmUrOqYdUponw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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