SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0495eafe04845467f5ec441aa89973faabc0d87f24d2d9a22eff3d86db319121' 
  AND token = 'fUiMWxUi94T3EkciQBWXszo8ZCGv3Wpg46pK2CTFA+M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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