SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09174ec2efed877ebd3f75689affbc27252cabba9ef2678d08735f8c223c4d9b' 
  AND token = 'SjRwivxHdScQcDMF/GzIoqZ8Cxet4JfcxwNMPy1hjbQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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