SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed04c8505479b3d79bc7d96824a0193b1b8eef57f295116800d5c6fdbec38876' 
  AND token = 'G4LS5ChXDyKB56uHWLa0KvVk+6oEYXw9K1vDVTYZLXw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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