SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2051b73379109729168939cb065fb3d5fcd5f353defe444a4787c8239f8945d6' 
  AND token = 'Z25Qf65CZtu+RATDuXmGylUTf4pEwyBEsYjsHfqQLE0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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