SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a8c310f7185eb937c81f28740c95d1250615bf30c555278d4ebd4ec828f27d1' 
  AND token = 'eopEJyI5CUJUK8BMv0kINYzdZnCaJ2EB46AEQ8Uf6uU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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