SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '595ffe7f5e84a5c81b7b54b8cf664ea45c95789a11838db5ebd392f2a252307b' 
  AND token = 'FmkEzBj9k0C91lv9oDnfusXGDpmLZZC4pYOCcnVJvmI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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