SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '951a454c24388444eb02f3a25951863eb7ec482223b02060bcbf5c1d72e2bdbd' 
  AND token = 'AfkBnOAmdI8F7nyTKODtHEaRV6ksTlYyOqpaXyZJ11M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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