SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a8fd7777af423ec01ac27a29ae7f7b0af3a7c1960ddc2740c21252462730ca7a' 
  AND token = 'WR+7+97Yaq2wNO1qaltXPKML1N2/A7gXRRIpTnbVyz8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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