SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f05291888f2a8aadd07aeac5ff11eac76dd4b422ef13f0dbf1247d607dd280cf' 
  AND token = 'KzAEs1CXsiKF65SJYj2JXZkoV/BIRSyQJvSy42z/oPQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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