SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33ff797d67cd2326c5a17a750b153c8ef673eafea68b279aabc1289f5c0d12c4' 
  AND token = 'PZtrbXmzGRv7RzW/t7ylFTgNhUf2YVzEI/tV1OO4hp0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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