SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99dae1882a836b2f214909add153135cd9ec05ffad5f678520a08ca626aa49ed' 
  AND token = 'Cpp3A0DdFHllozOoWwEnHUkZWcfTP0Kz1cWtja31fa8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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