SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '78eb517553618eab6ebf74b6590b29af1da9cdcac46aacc23062d07b995757e5' 
  AND token = 'bwLmtL2T/bKnMfu+zD04WTzvej4YUHVr77A0VLHKhOE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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