SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '844b6ad7c62daadc5acf401976cd6de25634de413b32c095a7841064ab917121' 
  AND token = 'zafMK9gqpPmLNRYs1Wz4FHG7+qirrVel0vrxpRN7G+c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00110

JSON explain

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