SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3342e2de2c6b18f2fa1f1004b13d920eb4ab9926963852883145569cc9a57abc' 
  AND token = 'pHDhifHNl8tHuilbPg2i3ygIQqj5U69MlzhTqT0gVRw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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