SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ffcae74bee57aa97a93cd13761bef212dfbde65235202efc978de82931c56eaf' 
  AND token = 'rA0+Gc388XYoVMO8zEoqGeK1MkXp/ZwEc70XMmSHdL4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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