SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fc0199af66fb57c6fd8864f6ec7729eea6444f1205d749314a93adac5a935d2' 
  AND token = 'ofp+JbLRrqNWmK9nfu9V9NWwRG8+woqBUbQy/PKEL+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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