SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd86b72daa88872613c6859f813f51f8980a3955b475cdc5f1ea2a9c67447896b' 
  AND token = '4xy0mN6XF9swsKtaIO6K2NhVuKgJfLg+ojpbZe6mKhI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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