SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5fb8bd9ff746ccfb2e1b70b5fb10707a345da8a44225ce32019a2ae6cb76d677' 
  AND token = 'XqZyM/S5w9XG9bs9ewH3HXbvZedO9uVQB3+oRtv4jXg=' 
  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"
    }
  }
}