SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7cdfe711a49f08d17846391109f7e4828ca7db3383d24f94ec9d6ed0cb6dfd3d' 
  AND token = 'gtxGbByowxIwoV0tfg5e0/hICgu8VGcCYvIMtmdOgPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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