Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eedd62aa014f9f8a386fc7a8f6c68e4aa13aee7f2e1cc41f94d0003b600757d4' 
  AND token = 'ZxQ6Aiq14UJ3wDhZDLuw8wB1fK/HpAv4J0vmOxGtRQA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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