SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f6bc8b28c93a6cde39ec514fc3f0bad7205d4413c434480a3fefc2d5b176cfd1' 
  AND token = 'Lg64f1ZofvcZTevFaFb1myQ4zzPmVH165fMaB/IS8No=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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