SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd483a92c7d1f49fefb9f170b66a9c5c33741b296714d7710529de0c4cf65fba9' 
  AND token = 'ODUucB6jOes04DyrcA3eeigIzNFh9CzMwQqgpulHaMY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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