SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '69ef88dfbe8b5c955ebe943736055fdf4725ee58adb43f9a6761166f1978294f' 
  AND token = 'awaDiYcuiJI1fFM2ThL1f9h7digx/Jacq/jrebEfIKs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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