SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1b6a495f06fc6d81d7702ddbbe9049253ebd05f5dc666089e258447a1877f6e' 
  AND token = 'm0R0GzTGCJ2rqnjvQcCMfow8w8I5Yt6zCTCEBHkqyEs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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