SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2395756692c5035ea147a3041dfeb9b2fd669ca4702cfec349e781711112d109' 
  AND token = 'OBuG63MbnbL/JH0+CQYyeeRGhtathkxgUuAElg5DwVQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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