SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9ffbeb200e3e1054a753e7a4c98c3d264237a29393a5a14904276fe4d6a33b4c' 
  AND token = 'gtxlGNBB/MWOZ9Kpv36+RIhuSzVaktVvkYil09HLCJw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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