SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9a1136d2213c82bde01408dd5669813ceb069eb2d90b158b5d742654872e1649' 
  AND token = 'Rg//aswDUoWIsu0YpOuO98FU6nKACezXgrUXepM6Zkw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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