SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '213eb88c06b724eacda72a1f377c5f1d9f30de28d888bcc0510aeebdaaa8e773' 
  AND token = '+2kY1qkmYHAk/EeftggYklbyPJvOKx7j/PfgQnUn6dU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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