SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b49efe3c356dfef4481f8db7b7449d64e5eeeb0afb7983a1033a94b5609a131e' 
  AND token = 'Qgg1yFrNdIppWqLVDGUigl0cdlJ62tFCPKZjbpZg6Vs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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