SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b5ce122daa25f1d2e33ebcc5d1f5580b2f9557528143f9e0b5abb00c79c741d' 
  AND token = 'jw8uZZerJcmN1RkSAdbKMzBAlSkivsr+neIefjGNKQc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00081

JSON explain

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