SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '444c61772db44cccb0cfff5be1174ddfaca454524b54eb3a21d8de1fb9d78e16' 
  AND token = 'xlg6O9JwSffydVNqgP5zOVYQrNkQmviCrn6b1iB8ncc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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