SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae79d08ce5f87f6c91c0c22b8e3497c77dd7dbe27850a46c2d435fb44a1c9fd9' 
  AND token = '2OH0y3dX84TrSpt2wBlIz2+3Mh9mdFweueeqc0dXUfc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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