SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1daccaedd4153d8f7b35552e4780cc277c7d6ccb5a4802f43f45f564454edf8d' 
  AND token = 'yITzkbvkLSLPRuT6NtQcqVUe/2kdC8pIHysfMkmP2RI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}