SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a435fbbe1d4e321febeb4c73734ea639ce955b6115aa357cfe577e1c39ee88b' 
  AND token = 'AJcRHOaa3a6DbvzHkA3pZxYCpF3rPNDnf/0vacTxYuw=' 
  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"
    }
  }
}