SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4bb946e8a928faebdf89f86794752e4ac777beac3d8157073bff9172e112193' 
  AND token = 'GMFzSwHb/+bdsvzJpZbhXOjo794ZO02bjJv7dquF99c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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