SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b036ea8a8454174ef7920304bc25375c7fd2af53b7f1607008eee3bf6043041' 
  AND token = 'UX2Cz+j5LJyFUo3hZLWGiluLGjDrVzQ7tH2lCtCP200=' 
  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"
    }
  }
}