SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7353d23d19fe3f67cec1cd43ca7951188421bdac8e22c86b9d7622ec811f0d07' 
  AND token = '3fRMrdefotF0aChV3o4Azm+y6NgsWlsA5j0u8KvWgj4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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