SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '9a44c72451883c8003088f9814617fa64c6cb6fd0de477cf9a7a136ecd0ab5a2' 
  AND token = 'OaKjYifIGdtTsLPyP+b4+KHc94QqWV22/eWkQOInh0g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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