SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c71ce1422bd3b07193c33b6b9f0ffc9de601ccf05e9f9b8f72ef1d9ede6f848f' 
  AND token = 'spA917aRSrnvC67F4P763dAVY5jjzq/GJpHhEtQqZ0I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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