SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '417126b5b1e32da09dd2c79abe3e2d60c7ad8df340ebfdf1bc5efaecae19f7be' 
  AND token = '5GJBprJ55kptNRMBohV7cPn1W9JeiJw5Gbz5HR6+pio=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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