SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2360f9afdad85f39a50c6bf2ab3112ffc9e4026a9c5a263ad4634dd79f9a168e' 
  AND token = 'haQTgtEArCdhvDgiO3kcceilstBqvLVNtaCoqfBSAQw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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