SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a206b1141d8fd5dec8c559da12dde4d74822e215228eff0f7a88c99b0469ddd' 
  AND token = 'LTI+kF6ohsIB3Q9JBI+lbr4rgkaPGVZ8nysXFpvcaUc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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