SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'caad2904014881f22a6e8b46b4b36a930dfa18fa58d1a0694f7183188a9c2185' 
  AND token = '/2FDzzjqe4NoYU407T2KBNI89mg/7SG3NCKhPkZzmQA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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