SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9126f7d9872d113681e1c2b0c5d43f2532b4bf161cf1f0d831a30b86076c7f4' 
  AND token = 'RSOC5hQ2tec3SlePpA6g8PuMIo8t/FO/UEOoTcOSTFY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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