SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '84fe9efbd0f371012f5bc21d82f0cbd380f3bc72e0a6f7f5ba03a8faff731839' 
  AND token = 'qskQG9BdO7VnWEjAcL/4Y+SgeapSL/uzHHtKaG1xvqU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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