SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5f58a633047e39519723d2641f2f0f99b8c8cae3f86fbbbf5957f426dcf84923' 
  AND token = 'WvRJYfptHZDNDiIpi4cSr1CZ5IKRz0NB+/ueMm28xNA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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