SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4202be5ba53b58adb59af87a818d1c11d2811ccfb3272f6e315686e2c84c2823' 
  AND token = '+1wsKS8NWpd7ibQpjDpCaOKxcQ+Hm6Gies6jxyxSqxg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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