SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47600b51e2ac381f710f2fb448b6b48185bfbc4ad45d6ca92065821a39ff00d8' 
  AND token = '9XbyjmKuLc66g/jPwt8hhCr/VWSoxCK7jtpYKIpv8Bs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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