SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '028dcf128b111c400440fe691ec8dfc40185ac6e537f1f91981cf938bbe18fb7' 
  AND token = 'jVzWx7rL0ZX7WWwIb7TOpItfTCBCzSzMD9bJqZoEuiY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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