SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9501f4a77afafaa26e5c2ba1dad6479fdf685579d91875953465a7b6dcfc842a' 
  AND token = 'HeIfOpuePUCBPOaIUxnT7zh8tn/7io+7ieNBA6CCBkM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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