SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97df1a82bc3458826e221926d719a51eaa13ed7e4d1f8fd3c1c3ca8417f55c74' 
  AND token = 'gX5Ywd74gvAecogE8T0x97QFFDIP/yvYxF8zzIo5geU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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