SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95c8a48066723bc19fb6f0cbd31a43dd0308b39bfde569ec1e7ad909672f5d73' 
  AND token = 'ljjMM42jQov6/2sNBcKlIZ7EN/WvuM0tIyFFvtIKCTA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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