Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '194fd8bcd75d8603073412a1d1f644d6ca02c17a037cd39c7ee6b28abc6be26a' 
  AND token = 'S8JyMPhZIKUt+Ne+HK4T1cbMFMFpwZnKicJLzf1jgyg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}