SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0c09d1320be8c93018282816c875bf4a461a9d5338a40e443eba0053c835252' 
  AND token = 'bDzHoW3XovdPlW1+DqjYta/5BnkaFahOBO9+KgJLgV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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