SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3b4d9a3f842d58200ca8b0ae71bc8d31850ce1f60dc4304ea84d1c461e3ccaf6' 
  AND token = 'ovKvPdCzlAXDSRzabRacNEiRKM0h7edXP/a9ODuSTk8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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