SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ca7a92d1855f87b537b845df9d4b667a705130f6b031090e9954c679d516fbd' 
  AND token = 'TcI79p3wYVW8GzV2kQuCHr5A9Cj6UYtssrT6JjMSCRM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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