SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7a1bfffc67b5ab448b3d601aa23063ca1bbad35b4517198673ca59896f79942' 
  AND token = 'yKU/TTznt/NlgU+HUChJwVu6RMYbTc8KS9hbBHLmCdg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00213

JSON explain

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