SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '602a17b310292016596fd50c0e1e5a6481866401eae6a82e938ceae1be0297d1' 
  AND token = 'PZaxhZJTP7dxLmmiuW80k0nZWCRN5Z1NEPxTT5V8U+Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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