SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efd1b872d551a1979b0c80af4036600eea6b26f0361dc713b2433c56cc793177' 
  AND token = 'AMe2UspUnblvsamHfOxPuGbs7cN5VoNPbhaHFOdaugo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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