SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dfbe53b7dbcc441f49feb5feabe6e174effb8f942db1354f19bf5d2372b57fa1' 
  AND token = 'JJx1U5H8sSKHmoZqHuq2zgiSdRKixxo7gOhADGTb0iE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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