SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'af47c1966e360ef29d8040a522ea314f699c417f1def4887cc004db180838a9a' 
  AND token = 'lhzmJTcsi0oGX8/4x8WU0pmg6Lq31iZDFTK34tWWDxU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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