SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '66a19683f0d72a327e99f49e87edf6c659607377cd5a9fcc383d6bd7733204c5' 
  AND token = 'CrNXWVkb7vlTIOvJYXng9RGzpo/qz41KigcrORMhBzM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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