SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f85b5269d5eb362fc4648277dbd7a694e41a60f3fdc0e778daba0eca9f79704' 
  AND token = '91rDlI65tJd1E2rEhgBFJ0WyNGXpMlk+U+ann4YQunI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}