SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ee8280750db0f83c02e9382c1d0c5f37f7ce84d183b1ca7119bad8b1f34b650' 
  AND token = 'ItcolNAzKxNilL97jtv4ARiLEf+PJjX/4wxHGfdMfc8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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