SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01df296cc92153740b313861c065242cfbf69ebe1b9e330909989c878bcdc2e8' 
  AND token = '9awC5d9zIymZPn7HllFzeEvqVQUBmwYO8w5DINjiaQE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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