SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89074b4bedb134c205f41c6e22e6ddb99531c7e7262343644a49b9b763c0840d' 
  AND token = 'tZwHMtLERHNZ2718Wt1YXA6kfXFTRfe2NhNqcJaLkFA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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