SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9560b91c128326ecfc04e0de71723b5dcab20b9f4451748ce9fd874bf0c6a517' 
  AND token = '+vVL2cW+rU+xWX+usxLChGFwjCKYf8PncrYDrXsn7p4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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