SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89659ab4268d71707110723551828bc454091067479bae8439e690bb509ee1b8' 
  AND token = 'dt4TTgwSveTeMSHLIFBIrNrEMmZC7H7aOXE7k8Tv7qM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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