SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '859096e136b2c8d15f52a4efa36eae68a60c75d099da82e816e3bcf3126e092b' 
  AND token = 'QUJMLWJIEb0AUEEskLaJzJeCuRIXt3LuPpZUz4G6jNU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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