SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0d53912b2a90a2317afa7a9dc31070f478563fecf2b6540718a468cc7216bef' 
  AND token = 'xlb1Ycy8koMTdmHBHMJqLZoQFRmzP0Z51ykadkxMPkw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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