SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdca884ab2a8c34d9a1efcd1ea672044e9c84435909d2519f98c7fd3bd769bfe' 
  AND token = 'KB0NlhgAtl6wdbXzB4IotAP/jC5abYvBQrjKdeLVaYo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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