SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa73d61259843c68bb960b96970f25e924f28adb1ccbcfebc6e62d57e22fc987' 
  AND token = '+vnAGeMuKST4XpuXInQut5+2WRABXy/deQ/gDjOgfCI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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