SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61ec6b34f48cc5c4f788178caa0e8eb78bf5d403d946045591ee35a1810bc12d' 
  AND token = 'iUvArroIECs+pC5XcEOZkFSXwNCUrZzrBl3FSz6DS8k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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