SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63ba97fa8ad9e3ed8688c189c76c4826a8612088e6d5f76f640db56116ab7c52' 
  AND token = 'ZAclyUfs6yjUypiVjB6Zg1cSonUHZcFPGKX7PoTFXOw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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