SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a273efd5a7728f96b275597329be4de7a4b551ca6502de09d3e6c3630bc63ae5' 
  AND token = 'Mo1ZTiW115ZfCCERQ3caCd3kHJFushYnjo97PLUJwHI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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