Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ad6dc2bcc890a8aef59b3c4336a6a8314cf17ad33a0f5bbbd071f65cc666c8b' 
  AND token = 'u5FmixIbIwIbZ+sgOU8mQJ5LdNWhAWiHlN7o6TjAcNE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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