SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1be417b8bbfc2023487d57c477a4ed78fe47a328883297a918dbb262fedb66b2' 
  AND token = 'mNSnzmKtLjwSRkmKCPxrTORA0co2qDu9Fe57gbjLuMw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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