SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '542d499f711e77d97197315a3d9f8775f01fe9d4572070a0ad59e9adc33fc6ad' 
  AND token = 'sVXMUyUHK/pSvuenHqMM7vL0snSuc7HwIpPo7r18uNU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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