SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb942699db295077eda15b2fe35eb9c74411417841f401da42273ce5022bcf56' 
  AND token = 'qAD8NBRh/LQZYFZqXAM7bpcWSbln/f6x1+VhYWM01ME=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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