SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdc4431953b771f3b343453a9fb9ba36769bc8a486120c7396effdbc8fea73c5' 
  AND token = 'YOgnGtZzPgLNhjQSEi113Egwf/3e4zIvBZIFTdAn5yU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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