SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93fd8025b6f3594a21963ec4e8f5cc8bc55293d5d8e0ac893a4a9c05c3ef10a4' 
  AND token = 'o2MpmGB8th1GmIAYlS3fw25DeW9Wu3f/OmEdpCBVn80=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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