SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82953acb45dbc4ae1a11a3131dd13a2be3e19817dea69fcca16489e1904b7e17' 
  AND token = 'BGKBQ1Ohy/JbBkSuDmpPCkQ90OtB0av4g0b+Tzn37KM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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