SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '922dbfc872faf633f584277b637426c5ab0994d3458e398d834c69b38485aba5' 
  AND token = 'bXtbVtwDxFyUfbW6Uu0lvS1AHTN+kthUqSEnHirD99U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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