SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ed23c7a97f2959cede603cc6f264ea71a6eb045d6ecfedbf67ab994c4106fb9' 
  AND token = 'ad2s27+9KU9msR5P9Z28anfZcLcoEUa2UZwj30Zu3lQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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