SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d68f1a832e43bd8593a246bba4ebbc797e2919fe4ea25179cc59187df3a0a76' 
  AND token = 'HpuYLAfSp5e0uZeZL7SXV+Z/1yz6NgsjyqPL+OplZVM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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