SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4fdc8cdc70d62235ce6e87ee6ee4b8fc660bf7bc4a5a5ae2abd4900ac41b02d3' 
  AND token = '88Zwaf3fNOVhyO34gDAToIBEUKHTk3JTsFenPpfX19Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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