SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d653038cdc02c5e694e7c7365a21390401d9b5f7f2080bac680cd8fd6a0bbda' 
  AND token = 'tcJwj5bkGktgqVj342umqSTXKZLrprHsDwDsOgt0F4g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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