SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb68d04b067aa9fc6de9dfd83022b2a69b88421ae317c5895d6bc0d3c8b469e7' 
  AND token = 'yybIT2UClZVJCk2foKGxMP4CYCSP2pdKlvDw+b/Y17E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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