SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '141bbd9031bb6aaaa3500ea813796c56fcaa22e7edb21c78e8232800da304a9e' 
  AND token = 'WVOuSYLZ/qP5Za7aAZUWqruNTOtcXrgwAiTUVIqffHk=' 
  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"
    }
  }
}