SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59282df2c1add1daefd3317a9ef2b1c42e8bc7cc991593c29b4456446afb07a9' 
  AND token = 'bqr2+kh5FwALUnUdOxo8uZ4TNg7LwUvkXTqaYVQhmtg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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