SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2253128929b9ff7c57d70dad1c78c73e771b99d454f284dacfb606948685c35d' 
  AND token = 'ngesbGHJdfVANXuIPQhFtdaFp/dg9BA3kpmnWHDoKTA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00066

JSON explain

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