SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c4c07a74314b26b3f7463c77b3e6a58efc452cc12a78dcf8b9f6311d544ad75' 
  AND token = 'sZN9wLBbSShu4jaqYIsuE6LvgDXrNgWTGkAS31KdQXQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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