SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a6780cb614d963b8aa5d09aa836af7b80f07d6468529b7e3ab37ecc9222b291' 
  AND token = 'Eyp+brZ/P8EnrUxCuNpCPDF4VjYgLRsTe2bIq6twG9Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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