SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4a46fa8fe85be9228509882ce1db5e1e3175f377cc90ee66dd4ed3d1ae43c8fb' 
  AND token = '3pz+KIw5smDOGokOceuMRwkNUnLiXxq2bfbQdXwpLtw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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