SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34361b97f9e379ef38dee7836aa0cf09d1f5458bc05da4f2b4f2ec6331c1ea2b' 
  AND token = 'Px4BLIOwXZLrjtz0+M84FchNrGVv++VRMq3Qzz2P/9E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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