SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c365ed5463e96ad49bebd3b6005cd349e162349b1530547c86d40369de8568e' 
  AND token = 'PuQNJN1+hVxCPJQiuq09kjNNxJa3oxttaNXosgKUENw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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