SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8049b784f70b17e582f09393c2cd2b2226aba99a339103912101b529fa19eda' 
  AND token = 'uOoYR/NP2Yjvb9UPug05pMSwvzwB8CafcshGZpqj/7Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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