SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9aa692bf3e9b4c0c8ac5c267f7cd8581428fa293b5e0aa1d42de943a040f1c1e' 
  AND token = 'tnWejHrd0cQvwI8ER2Ro3QrANbSvBjYi0IdbD74quok=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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