SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab360a41288fdf98baf8a5edd70aea6dc59f2adfb6a05d915d1108568560369a' 
  AND token = 'imHVm0xbuXOaIUeK1vzi3S90mEp/M8c7LRs5ee98OWM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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