SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'aa42536824635b6aedeb4bf214539c1301991b45be07ac8f330e0cf0675a9be2' 
  AND token = 'ZUuC75oDKZ3NWI2qHwAu8h/HE5zgxhJj6IUvZ/wOH3M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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