SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '309082d5c3016ccd99f89b538188d22217dd22099877d4ebbc6480ea3d085116' 
  AND token = 'xnw0cuwZed7uBIcCqKBwOZaiWeVSUgJi7pmz4ypoTT0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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