SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26a6db50ba917cc0eb1cfe0972daf681ad89a9eb3625f6e92285479a7cc6b274' 
  AND token = 'MKAuw7VMT2xctl7Os6pgC06iH1691vm2lqcdo0UpjVo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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