SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9685f465a49299dd9437fdffd242ae710d898f56feb3141210bf0170596cab28' 
  AND token = 'eNUjf7hjJrickOrSpVQewuWJmiZDs34A01T9zMjq07c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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