SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a92761fe0198ee2f99a9b4f0e3d4dcf84ac50b7cce5aba761a63d91391de801e' 
  AND token = '7N0XhpRWfAVutTy3k962K/iQRegbbux9zRCqT16MFv8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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