SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1a1c235913d6fa49402987dfeeede51285f5ae7a88fbc38ea26de395087c39f' 
  AND token = 'lzCuzfmgid0A7fivAfsDQMRXtzT7+F9NWC0Cdt7h/Tg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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