SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e1c170a6bd3dbf328699bf99a6edbac15ba495d80f0dcca848fa13d7f3dae632' 
  AND token = '1RV0AphKPg+1FfJcMwcdt4knyfRI9wjJskzj8MpysY0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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