SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '448be1ccd947c245159d596ecf4c426e65ef79c32311e4c62e14bf2e2d144085' 
  AND token = 'dgHCFG3vqRU7TlJ+Gzj0KIJHWk5To01T7x1rXb9cmOA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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