SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '104d3e782bf29edba3e2fa102bacfcdcfe66774c47cd1b19fca9511fc714e11d' 
  AND token = 'h1v0DioD4EaG5T8GjjQBnbmx6HZVCXvtn1K2awhcxZc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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