SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c0c33c3e29b540539236668949dbd6953eb6883f70d0f537a416640081bb7e9' 
  AND token = 'MhZoFXLwpLE3VHQPsdgEoVkgN7OyMttCov0u4PAVxrA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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