Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '817a0d8218848d252b48aca43bb8ae365db2df987a2738e08d25c4f6c45cbf3c' 
  AND token = '37u9Cwjy8WIqS+sMYGQ+EqpzqAFZlaK2Sd+3+jEwQws=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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