SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10ee735b21183eff12b8f67cec5e733567ca35415d004650a48d6f71c2834174' 
  AND token = 'tey5EWFRluh46RWL8ECcmkrLiskNb1AvIgEmfR1dkFs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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