SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41178da77ab6e03d7f8f041aa2cdcb8957d596d49b01772152601c09a1b9d2f6' 
  AND token = 'b3L+DhZz3v6wOCV2IzkkJgzVd3v8esGALqaehH6wQV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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