SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'afee3b454874f680f07386885775bf05be50fda4f16a57764a3e0c6cce24858d' 
  AND token = 'uuEY55YHnkzN3BmV+CV/R4yBDxWYWz+qsgEZXtP28CY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00064

JSON explain

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