SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49148230b3f394434f801fa569343f074fd74ae538c8220042e6bab214c63674' 
  AND token = 'JUVAeSvJqHa8z7FWpu6omQ0L+mGDx01PwOgn6iwLnCw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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