SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80fb75de7ec196832f9085481ad426c2cbfaeaaad1c6fa38e4289d1f642ea684' 
  AND token = 'zVzEF6ooykvQxWc6+nOXLiAYzaLgKLNu0q8gMbFZQ3A=' 
  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"
    }
  }
}