SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22b9626e85c592cb6239f1984d4c5d315d86d7fd3c42b18b85bcd72c49c51d71' 
  AND token = 'EdS2/oDOoOVXt0hO9XJ7z4NAdHYFKUdNf+kho1Xi3C0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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