SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd1f45565e597c822bb959fe4725028bdafc9f36b24256851fd14d595776ef292' 
  AND token = 'OUSQdbVtMg8d1hFoFXlB46ZofwTwmUf+5X98i6KkD2s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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