SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ae40d92d74e3457d1a1a46efdf64103c17e5c830c49123ce93ceba2b062ea94a' 
  AND token = 'RgxsySFEiTZivqLX1LMeAbtYOdKPRSRUQySgIkhBoBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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