SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '419a7bf4eaa16bddf0d97181c62ee786d166bc3ee7da83f37ff50fd23525b844' 
  AND token = 'TytTG9qrek/U54mhsntW89Hhm8XVDWUABlMKoYTW47k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}