SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a8452991a8f6a444df06d6eeb06b26efc6b022c9f57a3de1cad50ecb44e19837' 
  AND token = 'wUQfhE1Jxy+yv3lZYhkruMwnj8lCZON3AADsQVjjWCM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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