SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '94b0aa7814d76d79647f7f7a3718855c77837cfc1a9665a94127d717cb7f15b0' 
  AND token = 'pKv7tTp9A/UOhvG+CFElkWF1XB5B5zbCwHR3uph3Evg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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