SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f4430676e829cf0f719072a721292607bf00b2543f4a1f602074dbbcf4e3453' 
  AND token = 'ooXxfhIgZZv/DxpEHZzo7k+3MMLPYweZE2NypEzbIYo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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