SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '090b24284a2c8444dc5107e1b9972ebb9e589fbf637aad6bf8df322da15400b3' 
  AND token = 'TjFtdvhAhlisA9KmvpXu9arvKhjDVK4nyknoc2zm7Jg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}