SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ae812a64c1c3f2927918840b925c82148c638f759dcae9f8d2bc5b3e28482a1' 
  AND token = 'w74k5YgZsPnzHaShJxxbw0HuCZ6CTfgBAhyvD/nLJ8I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}