Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d686dbf0027466cf3e71b2eb5650ac1ec7ea567b02ca8216357fd0872aeabbf' 
  AND token = 'h3OwwPm5lTcjQ2dx5hjE+IrbsbzoVDWLGWNGvj4ecT8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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