SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '812c24b44658dc2b7aca55a9dcba012cef5d97227ada427448780ad49a8a9c84' 
  AND token = 'U06NgcdYrgPgjRFZsTc/FEzoTDuRMf7VeoX8HjpjyyQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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