SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47b29e1c6bd47a410d7d2f995f4b97abae98a31fa46c5589b329233941da67a7' 
  AND token = 'ZbTmwMB7ObNTGWPwL+Nu+3ZyQGYCUUhiqmh8iOvbvWs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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