SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e5199633c3e2bc8471a84792bd84aca9d0bed3956334b60c449fd036aad659c5' 
  AND token = 'Elddu+Rwr7kxAWfLjCqZVnqzphd7EN3TnbZ/9HhayDU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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