SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2345386a6b3365dac1709d59ab6099e0c9b27be1560e73b94a10ba94062a64b' 
  AND token = 'UAzZyzLjBW5QIVLVZaHpO08fm80XdgbjOcnd2LTuWws=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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