SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ff7053cf3c5507c0856a97aeabf6c0f8a66330515acf48f03d3db2f83f5e702' 
  AND token = 'lGpgvvDJA0gzIc09Nl5H7atptJiqwKRUQ6kla/bPbFw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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