SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e04f8c5079035a65012663cc1d9d5c1771f4761c4ff573335848e9250fbd9309' 
  AND token = 'MAbxZa84Tc3pldV5eXH71iLe68kt9HdrGhtLuBktWj4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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