SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '743248dee15c31aabae261e811f8b20c57ebf3fb4ce99cae2f3f861457725862' 
  AND token = 'AFCKXDn0bGE6cYRSlyM0GXSog3yRVm87SKQn8v0H3Nw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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