SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4db9474627e78ddf7adeb01c3ba44a4f9be37985cc5830ae829450baff0f87de' 
  AND token = 'FZMAiUNMIF1D+S68eKZBsPmg2KkyR+iUujTPMhJoTVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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