SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4293dc8232840ab814eafecdba42fdf2b8ea3d27bf7c59fb905ef02ebaccec2b' 
  AND token = 'Fyab+0vE5LZCj2o06T73+OfDSz2xTBLfDtVX55FST1I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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