SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63b504c3a5b073c4d7a271c17c30b2f0f991b6ef9f8989ec5ae708c53861d656' 
  AND token = 'nVAGQfQ7FX//Gz0AiBr7iCbq+cCYNml/x0VjlZKH9uA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00059

JSON explain

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