SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b8b5cca427733b4b4a6ee937bdfdcad43721c88e61f955774b42c3fa089628ab' 
  AND token = 'GMyqXXJViALM/nYbSwCpMeF1R8DzWyA3DVei6eQJEuk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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