SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94bb5b959d048ac6c16a3c4cc3d810519b91e49562cea6ce20bf26bc4709b728' 
  AND token = 'HK6XXc14dwzz3YOYGxaEdiXlfnWwRHM+Gb1REZCZ1RA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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