SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a33728b3e06bcdaebe90445d9af59cb2ddc09fa77637a1f44358fc948855801' 
  AND token = 'Uo6GzgA4GV09xWUKh+OoTTiqgrX29ZRFK7zgHgpkxiQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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