SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3e2cddf40ca6024bedaa3f35d6015fe050401f08f4b00b4544ab287619e08a35' 
  AND token = 'CkCANQ3uVeGtItNaO33NtZLhNgWNlL9Lm1qc2MAWOtw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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