SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '79938562544b213d90518d1a4225fe81905d6835afa53207852a08c14704c44c' 
  AND token = 'ciT8lmNRaB2NH6/HnXubxTonWBE/lZMK/suCUqVvCas=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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