SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b7eb3b1a43c221921b1b5474944cf504fb754a12dffa9171c117490f5cc4adc8' 
  AND token = 'EV6+3Nzvz/v6KjE2TufFpJDlUXqU+hTtCPDIWX1+v88=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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