SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2e234d2f8c083d9be287cd950dcd921dbacd9b0fa5ed085315fe19002c2ff4c0' 
  AND token = 'lTPH68sJ+/vG4dvflk6/5R+blFks7GdZznNqK4Pc/YA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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