SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fc5939e510cb77b7a22543ec81b2d9e5a8061f8db9b0f2490cc666f7ea82ba3' 
  AND token = '1d/fCil5wqg40L25uSlh02gapAaB1TYQxyCHD0juOrY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}