SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6af30d64503be6814b9383a4a45bfc114e5e7409b60d8da142ed2182c79c87c5' 
  AND token = 'Dt2D6wBQADpjtnA+U0Rt76gudQT97OqjuevF3aXnj3o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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