SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '078a283a6bef69cdda9a5d9b04ea111c3230dd9ee4d506f702dbbb1f7b2bbbaa' 
  AND token = 'S34xcnxYIQDcnW/8O+hQ1mLXLcpJq9PsDFGgrdZLhDA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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