SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '485e26b432a628965503fa19e1ca2178692cdc296a0bddfbed501c3844cd6917' 
  AND token = '03TefrA3FWwGwSybmK2QKZacAUS0OyhLHtE/iJMNA6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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