SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65638975beb868c645de2890c6e8fcf722f6e9aacbdbf5a6d48e57d11c7b4474' 
  AND token = 'qXqUwxGYvXhb1Z/5JMz1ovrYU1/WY/4lufwxtSY5XuI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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