SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '12a7bb5e3b3ef1df353e3dc28ed8266c5850d3075280387c4734c517e4039b98' 
  AND token = 'KtRwIweaJtXZtvupOOcXlXPKWU0kqvcthMYBRM7Hhug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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