SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a85e6187bf3667c8308ae598e6f07d2a760eaed5bc49bc5e7ee39a68808b26cb' 
  AND token = 'dNocNKUHBTM23q/TZuCMsygkXFcYK3XH8mFqB6cg3Ao=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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