SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1eb2547ca7331e398479e692613fdf72af63f6fef2a95574d511d9d511e8cc37' 
  AND token = 'IFWtnWRbUQLM1dBb4y7AfIwUlNrnuPsTBEA8PkdrW1o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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