SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c3235d4dceee8e99c5540c87e2813b102a2f96a3c64c09bee390dbc2340b911f' 
  AND token = 'GHoQBk9vgLqu0tVQ2nn1mJmVwzk8rmNCKwjhbPqJW0w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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