SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ea150b09c80084de313f9c874b19ad06c4df3a9ab44e52c697fed17d6dc556a' 
  AND token = 'BZ9xTDyIQHBHLYfXnw5biAc5ocng+u5zOdnV6B8GJyQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}