SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd00ca39ce0b37fb7c52ba52138b1014facd639373d3fdcdb2d63ac098106c777' 
  AND token = 'fNLM0s9PfiHcQrwEjzUhknVvsdWjxJKNxr0Jz+OV0LY=' 
  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"
    }
  }
}