SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfe5f148ebfe0f5f8f4499bd27e16f9e86ae041102d3eadf21eedf2f321e817f' 
  AND token = 'FRTvTywQVTzwpH/DpeL5mQbyycykFXEHnm2NngxWij0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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