SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd89da3fcee5100f3a96ce0489e6658ee28d1cdbb70cc95cb81ba5710eb56b2b' 
  AND token = '4qaFJcLPFPlyokKJ73SIVhKQZhuDl2HRfgm/+pvYXOw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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