SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8da1600b9dfd502f2989dc00582bc1ff6a46bfb847536afd1ec868973b01231e' 
  AND token = '9K7hbSlIfUqHLz3RMzyxspCI0C0ff5Cyxrg5IZ72BZY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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