SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bb4cba0cc1f66c84a2cb4a3e83342b642eea8e92be171932e9c1e0b7fee7c803' 
  AND token = 'c5Kn5drSMhAhnX/laSDpkWBsvNtPOG2BUai6qE3+zlw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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