SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0e8e88218169f4ed21a746ce025fab14dc4f3b5671b3a7c18617dafdd7b3e4ab' 
  AND token = 'Xj4Tb6JY/yBK6iGM/aRBCZNK3V4yiiunNywFodR3s+E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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