SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '66530209c97e754237e3eb729702833adeb6feca519bdcf5666cf7c34701653b' 
  AND token = 'wWsXb+8bYqI5DNW9cnpf8TllL8ZgUsZpZuuLr6wjjzg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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