SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bca72d8518aae828990e88abf46c753657780501a3865f2fab44a500ab087107' 
  AND token = 'cfIB95RMXTGNxdzlUpaSUA2TGjmbQ7YrPKM/eiEEBFA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}