SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c87be85085c8a87980dd90e53c766f59570d763b412a42973ae86d3dac684aa' 
  AND token = 'jpxYr/grIrxOVcE4zunT3AvKgECEVZ7xaHDTeQdPizw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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