SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2d1da4bb239ab0268df31f911e1296c4cc44629f897da042e3e73bbbd9afe9b' 
  AND token = 'WHCN34ptPOeBRciGTNRRDSaVkUtd4+OIiasBfwuCn8o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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