SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '527c0ba521907d7de760b39eb162cb3098a0343edecfdf62080fcee6fae3cb9a' 
  AND token = 'pvvubHr0aYuV09YwjVngK2C/F035hEjZHPpIPodR4vU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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