SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '306d35592cf9ed5ef216ed24266c66f7a59a88039415f00b713398dc8bb833b8' 
  AND token = '0bda7h3tDCf6Pop4+y5/4ffJ8JR57ZRMQLDg6Jpd6T4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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