SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '57a2a36a104bd9ec71c35ec90ea359073e6cc109b78412c793ec1a242c82c6de' 
  AND token = 'TH/ck1RyodrL73cR1AigrifYUfHVALa+ZCwcn3gUPd4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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