SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '050498b70488d5c245a05e457864c1c33343257b483d7093d106695167ae25b3' 
  AND token = 'GwzBFt6Mh1GbNfHtCRbtg8MvDeQsY/InjSPNHuoau1k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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